Tag Archive for: zika

Measuring preschoolers’ cognitive development in Latin America

A blue background showcases a brain made of gears, symbolizing the intricate workings of the mind.A blue background showcases a brain made of gears, symbolizing the intricate workings of the mind.

Neurodevelopment occurs at a rapid pace during the preschool years, research shows.

Measuring and tracking development in early childhood is important for understanding how to best support long-term positive health outcomes for children. However, the art of selecting measurement tools that are appropriate for a given study sample is complex; variations in language, cultural relevance and adaptations, availability of normative data, and more can impact the administration and interpretation of study findings.

In a recent study published in the Journal of Pediatric Psychology, the authors systematically review the standardized neurodevelopmental assessments used to study preschool-aged children’s cognitive development in Spanish-speaking Latin America.

“Thinking critically about the ways we measure these outcomes is an important first step in conducting ethical and accurate global research,” said Meagan Williams, M.S.P.H., C.C.R.C., senior clinical research coordinator for the division of Infectious Diseases and the Zickler Family Prenatal Pediatrics Institute at Children’s National Hospital and corresponding author of the study.

The hold-up in the field

The field of child development research is complicated by the presence and use of many different neurodevelopmental assessment tools, only some of which are standardized and use norms to allow researchers to compare their cohorts’ performance with population-level data.

“Many cognitive assessments, including some of the most commonly used assessments identified in our review of research conducted in Spanish-speaking Latin America, have only been officially normed in the United States,” Williams added. “Others have been translated into Spanish and normed in large countries such as Mexico or Spain, but Latin America is a large and culturally diverse region, and it is unclear whether these normative samples are generalizable and culturally relevant to other regions of Spanish-speaking Latin America.”

This systematic review outlined 41 different neurodevelopmental assessments used in 97 studies, including information about each study’s sample, use of each measurement tool and findings related to child cognitive development. The review goes into detail about the most widely used assessments, including background information of each assessment and trends in how authors of the studies in this review reported their methods and results.

Moving the field forward

When researchers use similar methods and valid outcome measures across studies, it becomes possible to combine data between cohorts and draw stronger conclusions about child outcomes. For example, The Wechsler Preschool and Primary Scale of Intelligence (WPPSI) was identified as the most used tool to measure intelligence of young children ages 2-6 in the systematic review. The WPPSI is also one of many assessments that Williams’s research team, led by Sarah Mulkey, M.D., is using to measure neurodevelopment among children exposed to Zika virus in utero.

“If researchers studying longitudinal outcomes after Zika virus exposure also use the WPPSI for their study samples – and if they openly report on their methods, adaptations, and sample characteristics – then it may be possible to harmonize data from multiple cohorts and draw stronger conclusions across studies,” Williams said.

But even the most popular and widespread assessments such as the WPPSI are not without their limitations. While norms exist for regions such as the United States and Mexico, additional work needs to be done to appropriately adapt and validate these tools for use in other populations.

Benefiting patients

Neurodevelopment occurs at a rapid pace during the preschool years. The earlier neurodevelopmental delays can be identified, the earlier experts can administer interventions to respond to these delays and help children get back on track with their peers.

This is particularly salient for research conducted in low- and middle-income countries, where socioeconomic, environmental and other exposures that are known to impact child development differ from those in higher-resource settings. Internationally, there appears to be significant variability in not only the assessment tools which are selected for use, but also in the methods reported across studies to conduct and interpret these assessments.

“By coming together as a field and prioritizing the use and validation of common and culturally appropriate assessments, we can better understand child outcome data on both an individual study level as well as on a broader population level, which will lead to a better understanding of the unique needs and strengths of the children we serve,” Williams said.

The team at Children’s National has been studying the neurodevelopment of children exposed to the Zika virus in Colombia since the beginning of the Zika epidemic.

“As our study on Zika virus has overlapped with the COVID-19 pandemic, we have had the opportunity to collect child outcome data at a very interesting time in history. We are excited that this review revealed that we chose a popular and well-studied assessment for our data collection in this region and we look forward to publishing our 5-year outcome data (which will include WPPSI data) in the coming year,” Williams and Mulkey concluded.

Dr. Mulkey is committed to studying the long-term neurodevelopmental impacts that viruses like Zika and SARS-CoV-2 have on infants born to mothers who were infected during pregnancy through research with the Congenital Infection Program at Children’s National and in collaboration with colleagues in Colombia.

Additional Children’s National authors include Madison Berl, Ph.D.

Exposure to Zika in utero may produce neurodevelopmental differences

Sarah Mulkey

“There are still many unanswered questions about the long-term impacts of Zika on children exposed in utero,” says Sarah Mulkey, M.D., Ph.D., a prenatal-neonatal neurologist in the Prenatal Pediatrics Institute at Children’s National Hospital.

Children who are exposed to the Zika virus while in the womb, but who are not subsequently diagnosed with Zika-related birth defects and congenital Zika syndrome (CZS), may still display differences in some aspects of cognitive development, mood and mobility compared to unexposed children, reports a study published in Pediatric Research. These findings suggest that Zika-exposed children may need some additional support and monitoring as they get older.

“There are still many unanswered questions about the long-term impacts of Zika on children exposed in utero,” says Sarah Mulkey, M.D., Ph.D., a prenatal-neonatal neurologist in the Prenatal Pediatrics Institute at Children’s National Hospital and the study’s first author. “These findings are another piece of the puzzle that provides insight into the long-term neurodevelopment of children with prenatal Zika virus exposure. Further evaluation is needed as these children get older.”

It has not been clear how children who were exposed to the Zika virus in the womb during the 2015–2017 epidemic, but who did not develop CZS and serious neurological complications, will develop as they get older.

Dr. Mulkey and colleagues examined the neurodevelopment of 55 children aged 3-5 years who were exposed to Zika in the womb in Sabanalarga, Colombia, and compared them to 70 control children aged 4-5 years who had not been exposed to Zika. Assessments occurred between December 2020 and February 2021. Health professionals tested the children’s motor skills (such as manual dexterity, aiming and catching, and balance) and their readiness for school (including knowledge of colors, letters, numbers and shapes). Parents completed three questionnaires providing information about their child’s cognitive function (such as memory and emotional control), behavioral and physical conditions (such as responsibility and mobility), and their parenting experience (including whether they felt distress).

Parents of Zika-exposed children reported significantly lower levels of mobility and responsibility compared to control children, although differences in cognitive function scores were not significant. Additionally, parents of 6 (11%) Zika-exposed children reported mood problems compared to 1 (1%) of control children, and Zika-exposed parents were significantly more likely to report parental distress.

Professional testing revealed no significant differences in the Zika-exposed children’s manual dexterity, such as their ability to catch an object or post a coin through a slot, compared to the control children. Both Zika-exposed and control children also scored lowly on readiness for school.

The authors highlight that parental responses may have been influenced by the Zika-exposed children’s parents’ perceptions or increased worry about the development of their child. Some differences in results may also have been caused by the age – and therefore developmental – differences between the groups of children.

The authors conclude that while these Zika-exposed children are making progress as they develop, they may need additional support as they prepare to start school.

Dr. Mulkey is committed to studying the long-term neurodevelopmental impacts that viruses like Zika and SARS-CoV-2 have on infants born to mothers who were infected during pregnancy through research with the Congenital Infection Program at Children’s National and in collaboration with colleagues in Colombia.

Researcher to decipher how viruses affect the developing brain with nearly $1M NIH award

zika virus

Zika virus in blood with red blood cells, a virus which causes Zika fever found in Brazil and other tropical countries.

The National Institutes of Health (NIH) awarded Children’s National Hospital nearly $1M of research support toward uncovering the specific cellular response that happens inside a developing brain once it is infected with a virus, including how the neuron gets infected, and how it dies or survives. The research is expected to gather critical information that can inform prenatal neuro-precision therapies to prevent or attenuate the effects of endemic and pandemic viruses in the future.

“We need to use all of the information we have from ongoing and past pandemics to prevent tomorrow’s public health crisis,” said Youssef Kousa, MS, D.O., Ph.D., neonatal critical care neurologist and physician-scientist at Children’s National. “There is still here a whole lot to learn and discover. We could eventually — and this is the vision that’s inspiring us — prevent neurodevelopmental disorders before a baby is born by understanding more about the interaction between the virus, mother, fetus, and environment, among other factors.”

Different viruses, including HIV, CMV, Zika and rubella, injure the developing brain in very similar ways. This line of work was fostered first by the clinical research team led by Adre du Plessis, M.B.Ch.B., and Sarah Mulkey, M.D., supported by Catherine Limperopoulos, Ph.D., chief and director of the Developing Brain Institute at Children’s National.

The clinical research findings then led to the NIH support, which then inspired more basic science research. Fast forward to now, Kousa will study how Zika affects the human brain and extrapolate what is learned and discovered for a broader understanding of neurovirology.

The research program is supported by senior scientists and advisors, including Tarik Haydar, Ph.D., and Eric Vilain, M.D., Ph.D., both at Children’s National and Avindra Nath, M.D., at NIH, as well as other leading researchers at various U.S. centers.

“This is a team effort;” added Kousa, “I’m thankful to have a group of pioneering and seasoned researchers engaged with me throughout this process to provide invaluable guidance.”

Many viruses can harm the developing brain when they replicate in the absence of host defenses, including the gene regulatory networks responsible for the neuronal response. As a result, viral infections can lead to brain injury and neurodevelopmental delays and disorders such as intellectual disability, seizures that are difficult to treat, and vision or hearing loss.

The big picture

Youssef Kousa

Youssef Kousa, MS, D.O., Ph.D., neonatal critical care neurologist and physician-scientist at Children’s National.

The translational research supported by NIH with this award synergistically complements nationally recognized clinical research programs and ongoing prospective cohort studies at Children’s National to identify the full spectrum of neurodevelopmental clinical outcomes after prenatal Zika and other viral infections led by Dr. Mulkey and Roberta DeBiasi, M.D., M.S..

The award also builds upon strengths at the Children’s National Research & Innovation Campus, which is in proximity to federal science agencies. Children’s National experts from the Center for Genetic Medicine Research, known for pediatric genomic and precision medicine, joined forces with the Center of Neuroscience Research and the NIH-NINDS intramural research program to focus on examining prenatal and childhood neurological disorders.

Kousa received this competitive career development award from the National Institute of Neurological Disorders and Stroke of the National Institutes of Health under Award Number K08NS119882. The research content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

The hold-up in the field

Many neurodevelopmental disorders are caused by endemic viruses, such as CMV, and by viral pandemics, including rubella as seen in the 1960s and Zika since 2015. By studying Zika and other prenatal viral infections, Kousa and team hope to gain deeper biological understanding of the viral effects toward developing therapies for anticipating, treating and preventing virally induced prenatal brain injury in the long-term future.

To date, little is known about how viruses affect developing neurons and, as a result, prenatal brain injury is not yet treatable. To bridge the gap towards prenatal neuro-precision therapies, the research explores how genes regulate neuronal developmental and viral clearance by innovatively integrating three systems:

  • Cerebral organoids, which illuminate how a neuron reacts to a viral infection
  • Pre-clinical models that link prenatal brain injury to postnatal neurodevelopmental outcomes
  • Populational genomics to identify human genetic risk or protective factors for prenatal brain injury

Given the scope and complexity of this issue, the international Zika Genetics Consortium, founded in 2015 by Kousa and a team of leading investigators across the world, provides critical samples and resources for the third arm of the research by performing comprehensive genomic analyses using sequencing data collected from diverse human populations throughout Central and South America, which are not as heavily sequenced as Western populations. Through partnerships with the Centers for Disease Control and Prevention and NIH, the consortium’s database and biorepository houses thousands of patient records and biospecimens for research studies to better understand how viruses affect the developing human brain.

“It is inspiring to imagine that, in the longer term, we could recognize early on the level of brain-injury risk faced by a developing fetus and have the tools to mitigate ensuing complications,” said Kousa. “What is driving this research is the vision that one day, brain injury could be prevented from happening before a baby is born.”

The importance of following the Zika population long-term

zika virus

Invited commentary by Sarah Mulkey, M.D., Ph.D., prenatal-neonatal neurologist in the Division of Prenatal Pediatrics at Children’s National Hospital, emphasizes importance of studying the Zika population long term.

A simple measuring tape could be the key to identifying which children could develop neurological and developmental abnormalities from Zika virus exposure during gestation. This is according to an invited commentary published July 7, 2020 in JAMA Network Open and written by Sarah Mulkey, M.D., Ph.D., prenatal-neonatal neurologist in the Division of Prenatal Pediatrics at Children’s National Hospital.

Zika virus (ZIKV), first isolated in 1947 in the Zika Forest in Uganda, made headlines in 2015-2016 for causing a widespread epidemic that spread through parts of North and South America, several islands in the Pacific and parts of Southeast Asia. Although previously linked with no or mild symptoms, researchers discovered during this epidemic that Zika can cross from a pregnant woman to her gestating fetus, leading to a syndrome marked by microcephaly (decreased brain growth), abnormal neurologic tone, vision and hearing abnormalities and joint contractures.

“For the 90% to 95% of ZIKV-exposed infants who fortunately were not born with severe abnormalities at birth and were normocephalic, our hope was that these children would have normal neurodevelopmental outcomes,” Dr. Mulkey writes in the commentary. “Unfortunately, this has not been the case.”

Her commentary expands on a study in the same issue entitled “Association between exposure to antenatal Zika virus and anatomic and neurodevelopmental abnormalities in children” by Cranston et al. In this study, the researchers find that head circumference — a simple measure taken regularly at postnatal appointments in the U.S. — can provide insight into which children were most likely to develop neurologic abnormalities. Their findings show that 68% of those whose head circumference was in the “normal” range at birth developed neurologic problems. Those whose head circumference was at the upper end of this range were significantly less likely to have abnormalities than those at the lower end.

Just this single measurement offers considerable insight into the risk of developing neurologic problems after Zika exposure. However, notes Dr. Mulkey, head circumference growth trajectory is also key. Of the 162 infants whose heads were initially in the normocephalic range at birth, about 10.5% went on to develop microcephaly in the months after birth.

“Because early head growth trajectory is associated with cognitive outcomes in early childhood,” Dr. Mulkey writes, “following the head circumference percentile over time can enable recognition of a child with increased risk for poor outcome who could benefit from early intervention therapies.”

This simple assessment could be significantly augmented with neuroimaging, she adds. The study by Cranston et al., as well as others in the field, have shown that brain imaging often reveals problems in ZIKV-exposed children, such as calcifications and cerebral atrophy, even in those with normal head circumferences. This imaging doesn’t necessarily need to take place at birth, Dr. Mulkey says. Postnatal development of microcephaly, failure to thrive or developmental delay can all be triggers for imaging later on.

Together, Dr. Mulkey says, the study by Cranston et al. and others that focus on ZIKV-exposed children support the need for following these patients long term. Children exposed to ZIKV in the epidemic nearly five years ago are now approaching school age, a time fraught with more complicated cognitive and social demands. Through her own research at Children’s National’s Congenital Zika Virus Program and collaboration with colleagues in Colombia, Dr. Mulkey is following multiple cohorts of ZIKV exposed children as they grow. She recently published a study on neurological abnormalities in one of these cohorts in JAMA Pediatrics in January 2020.

“It’s really important to follow these children as long as possible so we’ll really know the outcomes of this virus,” Dr. Mulkey says.

False negatives: Delayed Zika effects in babies who appeared normal at birth

sleeping baby

Colombian infants exposed to Zika virus in the womb showed neurodevelopmental delays as toddlers, despite having “normal” brain imaging and head circumference at birth, a finding that underscores the importance of long-term neurodevelopmental follow-up for Zika-exposed infants.

Colombian infants exposed to Zika virus in the womb showed neurodevelopmental delays as toddlers, despite having “normal” brain imaging and head circumference at birth, a finding that underscores the importance of long-term neurodevelopmental follow-up for Zika-exposed infants, according to a cohort study published online Jan. 6, 2020, in JAMA Pediatrics.

“These infants had no evidence of Zika deficits or microcephaly at birth. Neurodevelopmental deficits, including declines in mobility and social cognition, emerged in their first year of life even as their head circumference remained normal,” says Sarah B. Mulkey, M.D. Ph.D., a fetal/neonatal neurologist at Children’s National Hospital and the study’s first author. “About one-third of these newborns who underwent postnatal head ultrasound had nonspecific imaging results, which we believe are the first published results finding a link between subtle brain injuries and impaired neuromotor development in Zika-exposed children.”

The multi-institutional research group led by Children’s National enrolled pregnant women in Atlántico Department, which hugs the Caribbean coast of Colombia, who had been exposed to Zika, and performed a series of fetal magnetic resonance images (MRI) and ultrasounds as their pregnancies progressed.

Even though their mothers had laboratory-confirmed Zika infections, 77 out of 82 of their offspring were born with no sign of congenital Zika syndrome, a constellation of birth defects that includes severe brain abnormalities, eye problems and congenital contractures, and 70 underwent additional testing of neurodevelopment during infancy. These apparently normal newborns were born between Aug. 1, 2016, and Nov. 30, 2017, at the height of the Zika epidemic, and had normal head circumference.

When they were 4 to 8 months or 9 to 18 months of age, the infants’ neurodevelopment was evaluated using two validated tools, the Warner Initial Developmental Evaluation of Adaptive and Functional Skills (a 50-item test of such skills as self-care, mobility, communication and social cognition) and the Alberta Infant Motor Scale (a motor examination of infants in prone, supine, sitting and standing positions). Some infants were assessed during each time point.

Women participating in the study were highly motivated, with 91% following up with appointments, even if it meant traveling hours by bus. In addition to Children’s National faculty traveling to Colombia to train staff how to administer the screening instruments, videotaped assessments, MRIs and ultrasounds were read, analyzed and scored at Children’s National. According to the study team, the U.S. scoring of Alberta Infant Motor Scale tests administered in Colombia is also unprecedented for a research study and offers the potential of remote scoring of infants’ motor skill maturity in regions of the world where pediatric specialists, like child neurologists, are lacking.

“Normally, neurodevelopment in infants and toddlers continues for years, building a sturdy neural network that they later use to carry out complex neurologic and cognitive functions as children enter school,” Dr. Mulkey adds. “Our findings underscore the recommendations by the Centers for Disease Control and Prevention (CDC) that all infants exposed to Zika in the womb undergo long-term follow-up, providing an opportunity to intervene earlier.”

An accompanying editorial by CDC staffers concurs, saying the study reported “intriguing data” that add “to the growing evidence of the need for long-term follow-up for all children with Zika virus exposure in utero to ensure they receive the recommended clinical evaluations even when no structural defects are identified at birth.”

In addition to Dr. Mulkey, study co-authors include Margarita Arroyave-Wessel, MPH, Dorothy I. Bulas, M.D., chief of Diagnostic Imaging and Radiology, JiJi Jiang, MS, Stephanie Russo, BS, Robert McCarter, ScD, research section head, design and biostatistics,  Adré J. du Plessis, M.B.Ch.B., MPH, chief of the Division of Fetal and Transitional Medicine, and co-Senior Author, Roberta L. DeBiasi, MD, MS, chief of the Division of Pediatric Infectious Diseases, all of Children’s National; Colleen Peyton, PT, DPT, of Northwestern University; Yamil Fourzali, M.D., of Sabbag Radiologos, Barranquilla, Colombia; Michael E. Msall, M.D., of University of Chicago Comer Children’s Hospital; and co-Senior Author, Carlos Cure, M.D., BIOMELab, Barranquilla, Colombia.

Funding for the research described in this post was provided by the Thrasher Research Fund, the National Institutes of Health under award Nos. UL1TR001876 and KL2TR001877, and the Leadership Education in Neurodevelopmental and Related Disorders Training Program under grant HRSA/MCHB T73 MC11047.

Children’s National/NIH team competes in #IDbugbowl

Dengue virus

IDBugBowl team member Maria Susana Rueda-Altez, M.D., hopes her knowledge of infectious diseases common to Peru, like dengue virus, will give her team an advantage.

It’s a bird. It’s a plane. No, it’s an infectious agent that zipped past country borders, infecting international passengers who shared the same commercial aircraft as a person who had symptomatic illness.

The buzzer rings. And the correct answer is: What is severe acute respiratory syndrome?

This fall, a combined team from Children’s National in Washington, D.C. and the National Institutes of Health (NIH) will compete against three other teams testing their collective infectious disease knowledge through IDBugBowl, a Jeopardy-style quiz geared toward fellows, residents and medical students. The competition is held during IDWeek2019. “From anaplasmosis to Zika, any topic is fair game,” according to organizers.

“BugBowl has become so popular that the IDWeek 2019 program committee carved out a separate time for the contest to ensure it would not conflict with any other symposia,” says Roberta L. DeBiasi, M.D., MS, chief of the Division of Pediatric Infectious Diseases at Children’s National. “On a day-to-day basis, we all contend with serious infectious diseases that have the potential to jeopardize human health. However, this event helps to expand knowledge among the general public in a fun and engaging way.”

The Children’s National/NIH team participating in the Oct. 5 trivia contest includes:

  • Kevin Lloyd, M.D., third-year pediatrics resident
  • Maria Susana Rueda-Altez, M.D., third-year pediatrics resident
  • Kanal Singh, M.D., fellow, adult infectious diseases at the National Institutes of Health (NIH) and
  • Alexandra Yonts, M.D., fellow, pediatric infectious diseases at Children’s National

Even though she has little formal training in infectious diseases, team member Dr. Rueda-Altez says: “One thing I have in my favor is that I’m from Peru. We’re used to seeing infectious diseases that are less common elsewhere, including tuberculosis and hantavirus.”

And while disease-carrying mosquitoes aren’t abundant at Peru’s higher altitudes, closer to sea level and in its rain forests, infected mosquitoes spread chikungunya, dengue, malaria and Zika, she adds.

Take this quiz to test your infectious disease knowledge.

Paradoxical outcomes for Zika-exposed tots

In the midst of an unprecedented Zika crisis in Brazil, there were a few flickers of hope: Some babies appeared to be normal at birth, free of devastating birth defects that affected other Brazilian children exposed to the virus in utero.

In the midst of an unprecedented Zika crisis in Brazil, there were a few flickers of hope: Some babies appeared to be normal at birth, free of devastating birth defects that affected other Brazilian children exposed to the virus in utero. But according to a study published online July 8, 2019, in Nature Medicine and an accompanying commentary co-written by a Children’s National clinician-researcher, the reality for Zika-exposed infants is much more complicated.

Study authors led by Karin Nielsen-Saines at David Geffen UCLA School of Medicine followed 216 infants in Rio de Janeiro who had been exposed to the Zika virus during pregnancy, performing neurodevelopmental testing when the babies ranged in age from 7 to 32 months. These infants’ mothers had had Zika-related symptoms themselves, including rash.

Although many children had normal assessments, 29% scored below average in at least one domain of neurological development, including cognitive performance, fine and gross motor skills and expressive language, Sarah B. Mulkey, M.D., Ph.D., and a colleague write in a companion commentary published online by Nature Medicine July 29, 2019.

The study authors found progressively higher risks for developmental, hearing and eye abnormality depending on how early the pregnancy was at the time the infants were exposed. Because Zika virus has an affinity for immature neurons, even babies who were not born with microcephaly remained at continued risk for suffering abnormalities.

Of note, 24 of 49 (49%) infants who had abnormalities at birth went on to have normal test results in the second or third year of life. By contrast, 17 of 68 infants (25%) who had normal assessments at birth had below-average developmental testing or had abnormalities in hearing or vision by age 32 months.

“This work follows babies who were born in 2015 and 2016. It’s heartening that some babies born with abnormalities tested in the normal range later in life, though it’s unclear whether any specific interventions help to deliver these positive findings,” says Dr. Mulkey, a fetalneonatal neurologist in the Division of Fetal and Transitional Medicine at Children’s National in Washington, D.C. “And it’s quite sobering that babies who appeared normal at birth went on to develop abnormalities due to that early Zika exposure.”

It’s unclear how closely the findings apply to the vast majority of U.S. women whose Zika infections were asymptomatic.

“This study adds to the growing body of research that argues in favor of ongoing follow-up for Zika-exposed children, even if their neurologic exams were reassuring at birth,” Dr. Mulkey adds. “As Zika-exposed children approach school age, it’s critical to better characterize the potential implications for the education system and public health.”

In addition to Dr. Mulkey, the perspective’s senior author, William J. Muller, Northwestern University, was the commentary’s lead author.

Neuroimaging essential for Zika cases

zika virus

About three years ago, Zika virus emerged as a newly recognized congenital infection, and a growing body of research indicates the damage it causes differs from other infections that occur in utero.

Seventy-one of 110 Brazilian infants at the highest risk for experiencing problems due to exposure to the Zika virus in the womb experienced a wide spectrum of brain abnormalities, including calcifications and malformations in cortical development, according to a study published July 31, 2019 in JAMA Network Open.

The infants were born at the height of Brazil’s Zika epidemic, a few months after the nation declared a national public health emergency. Already, many of the infants had been classified as having the severe form of congenital Zika syndrome, and many had microcephaly, fetal brain disruption sequence, arthrogryposis and abnormal neurologic exams at birth.

These 110 infants “represented a group of ZIKV-exposed infants who would be expected to have a high burden of neuroimaging abnormalities, which is a difference from other reported cohorts,” Sarah B. Mulkey, M.D., Ph.D., writes in an invited commentary published in JAMA Network Open that accompanies the Rio de Janeiro study. “Fortunately, many ZIKV-exposed infants do not have abnormal brain findings or a clinical phenotype associated with congenital Zika syndrome,” adds Dr. Mulkey, a fetalneonatal neurologist in the Division of Fetal and Transitional Medicine at Children’s National in Washington, D.C.

Indeed, a retrospective cohort of 82 women exposed to Zika during their pregnancies led by a research team at Children’s National found only three pregnancies were complicated by severe fetal brain abnormalities. Compared with the 65% abnormal computed tomography (CT) or magnetic resonance imaging (MRI) findings in the new Brazilian study, about 1 in 10 (10%) of babies born to women living in the continental U.S. with confirmed Zika infections during pregnancy had Zika-associated birth defects, according to the Centers for Disease Control and Prevention.

“There appears to be a spectrum of brain imaging abnormalities in ZIKV-exposed infants, including mild, nonspecific changes seen at cranial US [ultrasound], such as lenticulostriate vasculopathy and germinolytic cysts, to more significant brain abnormalities, such as subcortical calcifications, ventriculomegaly and, in its most severe form, thin cortical mantle and fetal brain disruption sequence,” Dr. Mulkey writes.

About three years ago, Zika virus emerged as a newly recognized congenital infection, and a growing body of research indicates the damage it causes differs from other infections that occur in utero. Unlike congenital cytomegalovirus infection, cerebral calcifications associated with Zika are typically subcortical, Dr. Mulkey indicates. What’s more, fetal brain disruption sequence seen in Zika-exposed infants is unusual for other infections that can cause microcephaly.

“Centered on the findings of Pool, et al, and others, early neuroimaging remains one of the most valuable investigations of the Zika-exposed infant,” Dr. Mulkey writes, including infants who are not diagnosed with congenital Zika syndrome.  She recommends:

  • Cranial ultrasound as the first-line imaging option for infants, if available, combined with neurologic and ophthalmologic exams, and brainstem auditory evoked potentials
  • Zika-exposed infants with normal cranial ultrasounds do not need additional imaging unless they experience a developmental disturbance
  • Zika-exposed infants with abnormal cranial ultrasounds should undergo further neuroimaging with low-dose cranial CT or brain MRI.

MRI and ultrasound imaging detect the spectrum of Zika’s impact

Sarah Mulkey

“A combination of prenatal MRI and US was able to detect Zika-related brain abnormalities during pregnancy, giving families timely information to prepare for the potential complex care needs of these infants,” says Sarah B. Mulkey, M.D., Ph.D.

Worldwide, thousands of babies have been born to mothers who were infected during pregnancy with Zika, a virus associated with neurological deficits, impaired vision and neurodevelopmental disabilities, among other birth defects. These birth defects are sometimes severe, causing lifelong disability. But they’re also relatively rare compared with the overall rates of infection.

Predicting how many Zika-exposed babies would experience neurological birth defects has been challenging.

However, an international study led by Children’s faculty suggests that ultrasound (US) imaging performed during pregnancy and after childbirth revealed most Zika-related brain abnormalities experienced by infants exposed to the Zika virus during pregnancy, according to a prospective cohort study published online Nov. 26, 2018, in JAMA Pediatrics. Some Zika-exposed infants whose imaging had been normal during pregnancy had mild brain abnormalities detected by US and magnetic resonance imaging (MRI) after they were born.

“A combination of prenatal MRI and US was able to detect Zika-related brain abnormalities during pregnancy, giving families timely information to prepare for the potential complex care needs of these infants,” says Sarah B. Mulkey, M.D., Ph.D., a fetal-neonatal neurologist at Children’s National Health System and the study’s lead author. “In our study, we detected mild brain abnormalities on postnatal neuroimaging for babies whose imaging was normal during pregnancy. Therefore, it is important for clinicians to continue to monitor brain development for Zika-exposed infants after birth.”

As of Nov. 20 2018, nearly 2,500 pregnant women in the U.S. had laboratory confirmed Zika infection, and about 2,400 of them had given birth, according to the Centers for Disease Control and Prevention (CDC). While more than 100 U.S. infants were born with Zika-associated birth defects, the vast majority of Zika-exposed U.S. infants were apparently normal at birth. The sequential neuroimaging study Dr. Mulkey leads seeks to determine the spectrum of brain findings in infants exposed to Zika in the womb using both US and MRI before and after birth.

The international research team enrolled 82 women in the study from June 15, 2016, through June 27, 2017. All of the women had been exposed to Zika during pregnancy; all but one experienced clinical symptoms by a mean gestational age of 8.2 weeks. Eighty of those women lived in or near Barranquilla, Colombia, and were exposed to Zika there. Two U.S. study participants were exposed to the primarily mosquito-borne illness during travel to Zika hot zones.

All women received fetal MRIs and US during the second and/or third trimester of pregnancy. After their infants were born, the children received brain MRI and cranial US. Blood samples from both mothers and babies were tested for Zika using polymerase chain reaction and serology.

Fetal MRI was able to discern Zika-related brain damage as early as 18 weeks gestation and picked up significant fetal brain abnormalities not fully appreciated in US imaging. In one case, the US remained normal while fetal MRI alone detected brain abnormalities. Three fetuses (4 percent) had severe fetal brain abnormalities consistent with Zika infection, including:

  • Two cases of heterotopias and malformations in cortical development, and
  • One case of parietal encephalocele, Chiari II malformation and microcephaly.

Seventy-five infants were born at term. One pregnancy was terminated at 23 weeks gestation due to the gravity of the fetal brain abnormalities. One fetus with normal imaging died during pregnancy. One newborn who was born with significant fetal brain abnormalities died at age 3 days.

Cranial US and brain MRI was performed on the majority of infants whose prenatal imaging had been normal.  Seven of 53 (13 percent) Zika-exposed infants had mild brain abnormalities detected by MRI after birth. In contrast, postnatal cranial US was better at detecting changes of lenticulostriate vasculopathy, cysts within the brain’s choroid plexus (cells that produce cerebrospinal fluid), germinolytic/subependymal cysts and/or calcifications, which were seen in 21 of 57 (37 percent) infants.

“Sequential neuroimaging revealed that the majority of Zika-exposed fetuses had normal brain development. Tragically, in a small number of pregnancies, Zika-related brain abnormalities were quite severe,” Dr. Mulkey adds. “Our data support the CDC’s recommendation that cranial US be performed after Zika-exposed babies are born. In addition, there is clearly a need to follow these babies over time to gauge whether the brain anomalies we see in imaging affects language, motor and social skills.”

Companion editorial: Revealing the effects of Zika

In addition to Dr. Mulkey, study co-authors include Dorothy I. Bulas, M.D.Gilbert Vezina, M.D., Margarita Arroyave-Wessel, MPH,  Stephanie Russo, B.S, Youssef A. Kousa, D.O, Ph.D.Roberta L. DeBiasi, M.D., MS, Senior Author Adré J. du Plessis, M.B.Ch.B., MPH, all of Children’s National; Christopher Swisher, BS, Georgetown University and Caitlin Cristante, BS, Loyola University, both of  whose contributions included research performed at Children’s National; Yamil Fourzali, M.D., Armando Morales, M.D., both of Sabbag Radiologos; Liliana Encinales, M.D., Allied Research Society; Nelly Pacheco, Bacteriologa, Bio-Nep; Robert S. Lanciotti, Ph.D., Arbovirus Diseases Branch, Centers for Disease Control and Prevention; and Carlos Cure, M.D., BIOMELAB.

Research reported in this news release was supported by the IKARIA fund.

Multidisciplinary experts help CDC’s Zika research

“We are very excited about this next phase in our Zika research,” says Roberta L. DeBiasi, M.D., M.S. “It is a natural extension of our earlier participation as subject matter experts assisting as the CDC developed and published guidelines to inform the care of Zika-exposed and Zika-infected infants across the nation and U.S. territories.”

The Centers for Disease Control and Prevention (CDC) is funding three multidisciplinary experts from the Congenital Zika Virus Program at Children’s National Health System to collaborate on two of the CDC’s longitudinal Zika research projects in Colombia, South America.

“Zika en embarazadas y niños en Colombia” (ZEN) is a research study jointly designed by Colombia’s Instituto Nacional de Salud (INS) and the CDC to evaluate the association between Zika virus infection and adverse maternal, fetal and infant health outcomes. The study is following a large cohort of Colombian women from the first trimester of pregnancy, their male partners and their infants.

Under the six-month contract, Roberta L. DeBiasi, M.D., M.S., Sarah B. Mulkey, M.D., Ph.D., and Cara Biddle, M.D., M.P.H., will serve as consultants for the ZEN study providing expertise in pediatric infectious diseases, neurology, neurodevelopment and coordination of the complex care needs of Zika-affected infants.

The federal funding will underwrite the consultants’ work effort, as well as travel to the CDC’s headquarters in Atlanta and to research sites in Colombia. To that end, Drs. DeBiasi, Mulkey and Biddle participated in a December 2017 kickoff meeting, joining ZEN team leaders based in the U.S. at the CDC, as well as the INS in Colombia, with whom they will conduct research and collaborate academically.

Cara-Biddle-and-Sarah-Mulkey

Cara Biddle, M.D., M.P.H., and Sarah B. Mulkey, M.D., Ph.D., also will serve as consultants for the ZEN study.

“We are very excited about this next phase in our Zika research,” says Dr. DeBiasi, chief of the Division of Pediatric Infectious Diseases and co-director of the Children’s Zika program. “It is a natural extension of our earlier participation as subject matter experts assisting as the CDC developed and published guidelines to inform the care of Zika-exposed and Zika-infected infants across the nation and U.S. territories.”

Children’s National is leading its own longitudinal studies in Colombia that explore such questions as whether Zika-exposed infants whose neuroimaging appears normal when they are born experience any longer-term neurological issues and the role of genetics in neurologic injury following congenital Zika virus exposure and infection.

Children’s National experts contribute to new Zika guidelines

Roberta DeBiasi and Sarah Mulkey

Roberta DeBiasi, M.D., M. S., and Sarah B. Mulkey, M.D., Ph.D., members of Children’s multidisciplinary Congenital Zika Virus Program, were among the experts invited to participate in a forum held in Atlanta at CDC headquarters in late August to formulate new Zika recommendations.

The Centers for Disease Control and Prevention (CDC) on Oct. 19, 2017 updated guidelines for evaluation of women, fetuses and infants exposed to the Zika virus during pregnancy. Although only women with symptoms will now be routinely tested, asymptomatic and symptomatic infants born to these women will still be tested for the Zika virus using blood and urine tests.

Infants who appear normal, whose mothers either had negative Zika results or who had not undergone testing, will not undergo Zika testing. These infants still will undergo a standard evaluation, including a detailed physical exam, hearing screen and routine developmental assessments. The revised Zika guidance includes input from practitioners on the front lines of the Zika epidemic, including Children’s National Health System clinicians.

“These changes in the recommendations for Zika testing should not be interpreted as Zika infection risks subsiding for pregnant women and their infants in the United States. It’s simply an acknowledgement of the limitations of current testing methods – which must occur within a narrow window after Zika exposure – and the poor predictive value of Zika testing right now,” says Roberta L. DeBiasi, M.D., M.S., chief of Children’s Division of Pediatric Infectious Diseases. Dr. DeBiasi and Sarah B. Mulkey, M.D., Ph.D., members of Children’s multidisciplinary Congenital Zika Virus Program, were among the experts invited to participate in the Zika forum held in Atlanta at CDC headquarters in late August to formulate the recommendations.

While all infants will receive a standard evaluation, expanded evaluations that include an ophthalmologic assessment, more detailed hearing evaluation and ultrasound of the newborn’s head will be reserved for infants born to mothers confirmed to be Zika positive or Zika probable, or for infants born with abnormalities potentially consistent with congenital Zika syndrome, regardless of maternal status.

The majority of U.S. infants who have been exposed to Zika in the womb appeared normal at birth, according to CDC registries. Now, the next wave of these normal-appearing babies will receive standard evaluations when they are born, including a newborn hearing screening. At each well-child visit, these infants will receive:

  • A comprehensive physical examination
  • An age-appropriate vision screening
  • Developmental monitoring and screening using validated tools

“This is a natural evolution in the diagnosis and screening strategy now that the peak of the first wave of Zika transmission appears to be over,” Dr. DeBiasi says. “While we continue to evaluate new possible cases of Zika infection among pregnant women in our practice, a sizable proportion of Children’s cases are Zika-exposed infants whose physical exam and neuroimaging appeared normal at birth. Through ongoing monitoring, we hope to learn more about these children’s long-term neurodevelopment outcomes.”

Fetal MRI plus ultrasound assess Zika-related brain changes

Sarah Mulkey

Magnetic resonance imaging and ultrasound provide complementary data needed to assess ongoing changes to the brains of fetuses exposed to Zika in utero, says Sarah B. Mulkey, M.D., Ph.D.

For Zika-affected pregnancies, fetal magnetic resonance imaging (MRI) used in addition to standard ultrasound (US) imaging can better assess potential brain abnormalities in utero, according to research presented by Children’s National Health System during IDWeek 2017. In cases of abnormal brain structure, fetal MRI can reveal more extensive areas of damage to the developing brain than is seen with US.

“MRI and US provide complementary data needed to assess ongoing changes to the brains of fetuses exposed to Zika in utero,” says Sarah B. Mulkey, M.D., Ph.D., a fetal/neonatal neurologist at Children’s National Health System and lead author of the research paper. “In addition, our study found that relying on ultrasound alone would have given one mother the false assurance that her fetus’ brain was developing normally while the sharper MRI clearly pointed to brain abnormalities.”

As of Sept. 13, the Centers for Disease Control and Prevention (CDC) reported that 1,901 U.S. women were exposed to Zika at some point during their pregnancies but their infants appeared normal at birth. Another 98 U.S. women, however, gave birth to infants with Zika-related birth defects.  And eight more women had pregnancy losses with Zika-related birth defects, according to CDC registries.

The longitudinal neuroimaging study led by Children’s National enrolled 48 pregnant women exposed to the Zika virus in the first or second trimester whose infection was confirmed by reverse transcription polymerase chain reaction, which detects Zika viral fragments shortly after exposure, and/or Immunoglobulin M testing, which reveals antibodies the body produces to neutralize the virus. Forty-six of the study volunteers live in Barranquilla, Colombia, where Zika infection is endemic. Two women live in the Washington region and were exposed to Zika during travel elsewhere.

All of the women underwent at least one diagnostic imaging session while pregnant, receiving an initial MRI or US at 25.1 weeks’ gestational age. Thirty-six women underwent a second MRI/US imaging pair at roughly 31 weeks’ gestation. Children’s National radiologists read every image.

Three of 48 pregnancies, or 6 percent, were marked by abnormal fetal MRIs:

  • One fetus had heterotopias (clumps of grey matter located at the wrong place) and abnormal cortical indent (a deformation at the outer layer of the cerebrum, a brain region involved in consciousness). The US taken at the same gestational age for this fetus showed its brain was developing normally.
  • Another fetus had parietal encephalocele (an uncommon skull defect) and Chiari malformation Type II (a life-threatening structural defect at the base of the skull and the cerebellum, the part of the brain that controls balance). The US for this fetus also detected these brain abnormalities.
  • The third fetus had a thin corpus callosum (bundle of nerves that connects the brain’s left and right hemispheres), an abnormally developed brain stem, temporal cysts, subependymal heterotopias and general cerebral/cerebellar atrophy. This fetal US showed significant ventriculomegaly (fluid-filled structures in the brain that are too large) and a fetal head circumference that decreased sharply from the 32nd to 36th gestational week, a hallmark of microcephaly.

After they were born, infants underwent a follow-up MRI without sedation and US. For nine infants, these ultrasounds revealed cysts in the choroid plexus (cells that produce cerebrospinal fluid) or germinal matrix (the source for neurons and glial cells that migrate during brain development). And one infant’s US after birth showed lenticulostriate vasculopathy (brain lesions).

“Because a number of factors can trigger brain abnormalities, further studies are needed to determine whether the cystic changes to these infants’ brains are attributable to Zika exposure in the womb or whether some other insult caused these troubling results,” Dr. Mulkey says.

What Children’s has learned about congenital Zika infection

Roberta DeBiasi

Roberta DeBiasi, M.D., M.S., outlined lessons learned during a pediatric virology workshop at IDWeek2017, one of three such Zika presentations led by Children’s National research-clinicians during this year’s meeting of pediatric infectious disease specialists.

The Congenital Zika Virus Program at Children’s National Health System provides a range of advanced testing and services for exposed and infected fetuses and newborns. Data that the program has gathered in evaluating and managing Zika-affected pregnancies and births may offer instructive insights to other centers developing similar programs.

The program evaluated 36 pregnant women and their fetuses from January 2016 through May 2017. Another 14 women and their infants were referred to the Zika program for postnatal consultations during that time.

“As the days grow shorter and temperatures drop, we continue to receive referrals to our Zika program, and this is a testament to the critical need it fulfills in the greater metropolitan D.C. region,” says Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases and co-leader of the program. “Our multidisciplinary team now has consulted on 90 dyads (mothers and their Zika-affected fetuses/infants). The lessons we learned about when and how these women were infected and how their offspring were affected by Zika may be instructive to institutions considering launching their own programs.”

Dr. DeBiasi outlined lessons learned during a pediatric virology workshop at IDWeek2017, one of three such Zika presentations led by Children’s National research-clinicians during this year’s meeting of pediatric infectious disease specialists.

“The Zika virus continues to circulate in dozens of nations, from Angola to the U.S. Virgin Islands. Clinicians considering a strategic approach to managing pregnancies complicated by Zika may consider enlisting an array of specialists to attend to infants’ complex care needs, including experts in fetal imaging, pediatric infectious disease, physical therapists, audiologists, ophthalmologists and radiologists skilled at reading serial magnetic resonance images as well as ultrasounds,” Dr. DeBiasi says. “At Children’s we have a devoted Zika hotline to triage patient and family concerns. We provide detailed instructions for referring institutions explaining protocols before and after childbirth, and we provide continuing education for health care professionals.”

Of the 36 pregnant women possibly exposed to Zika during pregnancy seen in the program’s first year, 32 lived in the United States and traveled to countries where Zika virus was circulating. Two women had partners who traveled to Zika hot zones. And two moved to the Washington region from places where Zika is endemic. Including the postnatal cases, 89 percent of patients had been bitten by Zika-tainted mosquitoes, while 48 percent of women could have been exposed to Zika via sex with an infected partner.

Twenty percent of the women were exposed before conception; 46 percent were exposed to Zika in the first trimester of pregnancy; 26 percent were exposed in the second trimester; and 8 percent were exposed in the final trimester. In only six of 50 cases (12 percent) did the Zika-infected individual experience symptoms.

Zika infection can be confirmed by detecting viral fragments but only if the test occurs shortly after infection. Twenty-four of the 50 women (nearly 50 percent) arrived for a Zika consultation outside that 12-week testing window. Eleven women (22 percent) had confirmed Zika infection and another 28 percent tested positive for the broader family of flavivirus infections that includes Zika. Another detection method picks up antibodies that the body produces to neutralize Zika virus. For seven women (14 percent), Zika infection was ruled out by either testing method.

“Tragically, four fetuses had severe Zika-related birth defects,” Dr. DeBiasi says. “Due to the gravity of those abnormalities, two pregnancies were not carried to term. The third pregnancy was carried to term, but the infant died immediately after birth. The fourth pregnancy was carried to term, but that infant survived less than one year.”

Children’s National expert joins a national discussion on Zika and other emerging threats

Roberta DeBiasi

“Our goal is to provide the earliest and most accurate information to women affected by Zika exposure and infection during pregnancy, including capability for fetal MRI,” says Roberta DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases and co-director of the Congenital Zika Virus Program at Children’s National Health System.

An expert roundtable discussion, “Facing the Zika Crisis and Other Emerging Threats,” organized in collaboration with Purdue University, the Gallup Organization and the Bipartisan Policy Center, was recently held at the U.S. Capitol. Chief of the Division of Pediatric Infectious Diseases and Co-Director of the Congenital Zika Program at Children’s National Health System, Roberta DeBiasi, M.D.,M.S., weighed in on the discussion, sharing knowledge on the challenges to the United States health system and the continuous research and work that the Children’s National Congenital Zika program does.

Eighteen months ago, Children’s National received its first referral for a Washington, D.C. woman who had a Zika infected pregnancy in January 2016. This case prompted the development of the Congenital Zika program to serve as a consultation resource for affected women and infants, and to perform research to address the knowledge gaps concerning Zika infection during pregnancy: Young researchers tackle Zika’s unanswered questions.

“Our goal is to provide the earliest and most accurate information to women affected by Zika exposure and infection during pregnancy, including capability for fetal MRI,” says Dr. DeBiasi.

Since then, the Zika team has evaluated 65 mother-fetus/infant pairs. Researchers are actively learning the best methods for detection of infection and neurologic injury by continually conducting research and obtaining new and useful information that can be shared with others. The research mission of the Congenital Zika program is now focusing on several areas, which include the study of biomarkers to predict if the infant could be affected by the disease, the utility of a fetal MRI in conjunction with ultrasound, genetic risk factors in mothers and infants that might explain why some infants become infected and some do not, long term neurodevelopment of babies that are infected, and neuropathologic evaluations of brains from fetuses that have died from Zika.

The challenges and concerns that were presented for the United States health system include the willingness and ability to share information, the acceptance of the need for data sharing between institutions and determining if testing resources are adequate and appropriate.

Dr. DeBiasi says, “Institutions have become much better at looking at how to prepare for emerging infectious diseases on a broader level.” Proactively thinking, Dr. DeBiasi finds it useful for health systems to use their own task forces, such as the Ebola Response Task force at Children’s National, as a cohesive existing team that will be prepared for additional infectious disease threats that may arise.

Panel: Significant Zika risks linger for pregnant women and developing fetuses in US

Roberta DeBiasi

The threat from Zika “is not over. It is just beginning for the families who are affected by this,” says Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases and co-director of the Congenital Zika Virus Program at Children’s National Health System.

The Zika virus epidemic may have fallen off the radar for many media outlets, but significant risks continue to linger for pregnant women and developing fetuses, a panel of experts told staff working for U.S. Congressional leaders.

“The threat of this virus is real, and the threat continues,” Margaret Honein, Ph.D., M.P.H., of the Centers for Disease Control and Prevention’s (CDC) pregnancy and birth defects task force, said during the July 13 briefing held in the Russell Senate Office Building.

Dr. Honein told about 100 attendees that more than 200 Zika-affected babies have been born in the United States suffering from serious birth defects, such as rigid joints, inconsolable distress that causes them to cry continuously and difficulties swallowing. Some of these infants experience seizures that cause further brain damage.

Predicting what Zika will do next in the United States is very difficult, Dr. Honein said, adding that local outbreaks could occur “at any time.” A map she displayed showed Zika’s impact in shades of blue, with Zika infections documented in nearly every state and the highest number of infections – and deepest shade of blue­ – for California, Florida and Texas.

The threat from Zika “is not over. It is just beginning for the families who are affected by this,” agreed Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases and co-director of the Congenital Zika Virus Program at Children’s National Health System.

Since Children’s National launched its Zika program in May 2016, the multidisciplinary team has consulted on 65 mother-fetus/infant pairs, Dr. DeBiasi said. Because in utero Zika infection can result in a wide range of side effects, the Children’s team includes pediatric infectious diseases experts, fetal/neonatal neurologists to consult on seizures, audiologists to assess hearing, physical therapists and orthopaedists to contend with limb contractures, pulmonologists to relieve breathing problems and ophthalmologists to diagnose and treat vision disorders – among other specialists.

“You really need a program that has all of these areas of expertise available for a family,” Dr. DeBiasi told attendees. “It is not possible for a family to organize 27 different appointments if you have a child with these needs.”

Children’s Zika experts also collaborate with researchers in Colombia to gauge the ability of magnetic resonance imaging to produce earlier Zika diagnoses, to assess the role of viral load as biomarkers and to document Zika’s long-term impact on children’s neurodevelopment. The Colombia study has enrolled an additional 85 women/infant pairs.

In one presentation slide, Dr. DeBiasi showed sharp magnetic resonance imaging scans from their research study of a fetal brain at 18 and 22 weeks gestation that indicated clear abnormalities, including abnormal cortical folding. Ultrasound images taken at the exact same time points did not detect these abnormalities, she said.

Asked for advice by an attendee whose clinic treats women who regularly travel between California and Mexico, Dr. DeBiasi underscored the fact that Zika infection poses a risk to developing fetuses even if the pregnant woman has no symptoms of infection. “Whether or not they’re symptomatic, the risk is the same. It’s hard for people to understand that. That is No. 1,” she said.

Another challenge is for women who scrupulously follow the CDC’s guidance on lowering their infection risk while traveling. Upon return, those women may be unaware that they could still be exposed to Zika through unprotected sex with their partner who also has travelled, for as long as six months after travel.

Damage may lurk in “normal” Zika-exposed brains

Sarah Mulkey Columbia Zika Study

An international study that includes Sarah B. Mulkey, M.D., Ph.D., aims to answer one of the most vexing questions about Zika: If babies’ brains appear “normal” at birth, have they survived Zika exposure in the womb with few neurological repercussions? Dr. Mulkey presented preliminary findings at PAS2017.

It has been well established by researchers, including scientists at Children’s National Health System, that the Zika virus is responsible for a slew of birth defects – such as microcephaly, other brain malformations and retinal damage – in babies of infected mothers. But how the virus causes these often devastating effects, and who exactly is affected, has not been explained fully.

Also unknown is whether exposed babies that appear normal at birth are truly unaffected by the virus or have hidden problems that might surface later. The majority of babies born to Zika-infected mothers in the United States appear to have no evidence of Zika-caused birth defects, but that’s no guarantee that the virus has not caused lingering damage.

Recently, Sarah B. Mulkey, M.D., Ph.D., made a trip to Colombia, where Children’s National researchers are collaborating on a clinical study. There, she tested Zika-affected babies’ motor skills as they sat, stood and lay facing upward and downward. The international study aims to answer one of the most vexing questions about Zika: If babies’ brains appear “normal” at birth, have they survived Zika exposure in the womb with few neurological repercussions?

“We don’t know the long-term neurological consequences of having Zika if your brain looks normal,” says Dr. Mulkey, a fetal-neonatal neurologist who is a member of Children’s Congenital Zika Virus Program. “That is what’s so scary, the uncertainty about long-term outcomes.”

According to the Centers for Disease Control and Prevention (CDC), one in 10 pregnancies across the United States with laboratory-confirmed Zika virus infection results in birth defects in the fetus or infant. For the lion’s share of Zika-affected pregnancies, then, babies’ long-term prospects remain a mystery.

“This is a huge number of children to be impacted and the impact, as we understand, has the potential to be pretty significant,” Dr. Mulkey adds.

Dr. Mulkey, the lead author, presented the research group’s preliminary findings during the 2017 annual meeting of the Pediatric Academic Societies (PAS). The presentation was one of several that focused on the Zika virus. Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases at Children’s National, organized two invited symposia devoted to the topic of Zika: Clinical perspectives and knowledge gaps; and the science of Zika, including experimental models of disease and vaccines. Dr. DeBiasi’s presentation included an overview of the 68 Zika-exposed or infected women and infants seen thus far by Children’s multidisciplinary Congenital Zika Virus Program.

“As the world’s largest pediatric research meeting, PAS2017 is an ideal setting for panelists to provide comprehensive epidemiologic and clinical updates about the emergence of Congenital Zika Syndrome and to review the pathogenesis of infection as it relates to the fetal brain,” Dr. DeBiasi says. “With temperatures already rising to levels that support spread of the Aedes mosquito, it is imperative for pediatricians around the world to share the latest research findings to identify the most effective interventions.”

As one example, Dr. Mulkey’s research sought to evaluate the utility of using magnetic resonance imaging (MRI) to evaluate fetal brain abnormalities in 48 babies whose mothers had confirmed Zika infection during pregnancy. Forty-six of the women/infant pairs enrolled in the prospective study are Colombian, and two are Washington, D.C. women who were exposed during travel to a Zika hot zone.

The women were infected with Zika during all three trimesters and experienced symptoms at a mean gestational age of 8.4 weeks. The first fetal MRIs were performed as early as 18 weeks’ gestation. Depending upon the gestational age when they were enrolled in the study, the participants had at least one fetal MRI as well as serial ultrasounds. Thirty-six fetuses had a second fetal MRI at about 31.1 gestational weeks. An experienced pediatric neuroradiologist evaluated the images.

Among the 48 study participants, 45 had “normal” fetal MRIs.

Three fetuses exposed to Zika in the first or second trimester had abnormal fetal MRIs:

  • One had heterotopia and an early, abnormal fold on the surface of the brain, indications that neurons did not migrate to their anticipated destination during brain development. This pregnancy was terminated at 23.9 gestational weeks.
  • One had parietal encephalocele, a rare birth defect that results in a sac-like protrusion of the brain through an opening in the skull. According to the CDC, this defect affects one in 12,200 births, or 340 babies, per year. It is not known if this rare finding is related to Zika infection.
  • One had a thin corpus callosum, dysplastic brainstem, heterotopias, significant ventriculomegaly and generalized cerebral/cerebellar atrophy.

“Fetal brain MRI detected early structural brain changes in fetuses exposed to the Zika virus in the first and second trimester,” Dr. Mulkey says. “The vast majority of fetuses exposed to Zika in our study had normal fetal MRI, however. Our ongoing study, underwritten by the Thrasher Research Fund, will evaluate their long-term neurodevelopment.”

Adré J. du Plessis, MB.Ch.B., M.P.H., director of the Fetal Medicine Institute and senior author of the paper, notes that this group “is a very important cohort to follow as long as Dr. Mulkey’s funding permits. We know that microcephaly is among the more devastating side effects caused by Zika exposure in utero. Unanswered questions remain about Zika’s impact on hearing, vision and cognition for a larger group of infants. Definitive answers only will come with long-term follow-up.”

Many of the Colombian families live in Sabanalarga, a relatively rural, impoverished area with frequent rain, leaving pockets of fresh water puddles that the mosquito that spreads Zika prefers, Dr. Mulkey adds. Families rode buses for hours for access to fetal MRI technology, which is not common in Colombia.

“The mothers are worried about their babies. They want to know if their babies are doing OK,” she says.

Zika virus, one year later

Drs. DeBiasi and du Plessis

A multidisciplinary team at Children’s National has consulted on 66 Zika-affected pregnancies and births since May 2016.

The first pregnant patient with worries about a possible Zika virus infection arrived at the Children’s National Health System Fetal Medicine Institute on Jan. 26, 2016, shortly after returning from international travel.

Sixteen months ago, the world was just beginning to learn how devastating the mosquito-borne illness could be to fetuses developing in utero. As the epidemic spread, a growing number of sun-splashed regions that harbor mosquitoes that efficiently spread the virus experienced a ballooning number of Zika-affected pregnancies and began to record sobering birth defects.

The Washington, D.C. patient’s concerns were well-founded. Exposure to Zika virus early in her pregnancy led to significant fetal brain abnormalities, and Zika virus lingered in the woman’s bloodstream months after the initial exposure — longer than the Centers for Disease Control and Prevention (CDC) then thought was possible.

The research paper describing the woman’s lengthy Zika infection, published by The New England Journal of Medicine, was selected as one of the most impactful research papers written by Children’s National authors in 2016.

In the intervening months, a multidisciplinary team at Children National has consulted on 66 pregnancies and infants with confirmed or suspected Zika exposure. Thirty-five of the Zika-related evaluations were prenatal, and 31 postnatal evaluations assessed the impact of in utero Zika exposure after the babies were born.

The continuum of Zika-related injuries includes tragedies, such as a 28-year-old pregnant woman who was referred to Children’s National after imaging hinted at microcephaly. Follow-up with sharper magnetic resonance imaging (MRI) identified severe diffuse thinning of the cerebral cortical mantle, evidence of parenchymal cysts in the white matter and multiple contractures of upper and lower extremities with muscular atrophy.

According to a registry of Zika-affected pregnancies maintained by the CDC, one in 10 pregnancies across the United States with laboratory-confirmed Zika virus infection has resulted in birth defects in the fetus or infant.

“More surprising than that percentage is the fact that just 25 percent of infants underwent neuroimaging after birth – despite the CDC’s recommendation that all Zika-exposed infants undergo postnatal imaging,” says Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases and co-director of the Congenital Zika Virus Program at Children’s National. “Clinicians should follow the CDC’s guidance to the letter, asking women about possible exposure to Zika and providing multidisciplinary care to babies after birth. Imaging is an essential tool to accurately monitor the growing baby’s brain development.”

Adré du Plessis, M.B.Ch.B., M.P.H., director of the Fetal Medicine Institute and Congenital Zika Virus Program co-leader, explains the challenges: ”When it comes to understanding the long-term consequences for fetuses exposed to the Zika virus, we are still on the steepest part of the learning curve. Identifying those children at risk for adverse outcomes will require a sustained and concerted multidisciplinary effort from conception well beyond childhood.”

In addition to counseling families in the greater Washington, D.C. region, the Children’s research team is collaborating with international colleagues to conduct a clinical trial that has been recruiting Zika-infected women and their babies in Colombia. Pediatric Resident Youssef A. Kousa, D.O., Ph.D., M.S., and Neurologist Sarah B. Mulkey, M.D., Ph.D., will present preliminary findings during Research and Education Week 2017.

In Colombia as well as the District of Columbia, a growing challenge continues to be assessing Zika’s more subtle effects on pregnancies, developing fetuses and infants, says Radiologist Dorothy Bulas, M.D., another member of Children’s multidisciplinary Congenital Zika Virus Program.

The most severe cases from Brazil were characterized by interrupted fetal brain development, smaller-than-normal infant head circumference, brain calcifications, enlarged ventricles, seizures and limbs folded at odd angles. In the United States and many other Zika-affected regions, Zika-affected cases with such severe birth defects are outnumbered by infants who were exposed to Zika in utero but have imaging that appears normal.

In a darkened room, Dr. Bulas pores over magnified images of the brains of Zika-infected babies, looking for subtle differences in structure that may portend future problems.

“There are some questions we have answered in the past year, but a number of questions remain unanswered,” Dr. Bulas says. “For neonates, that whole area needs assessment. As the fetal brain is developing, the Zika virus seems to affect the progenitor cells. They’re getting hit quite early on. While we may not detect brain damage during the prenatal period, it may appear in postnatal images. And mild side effects that may not be as obvious early on still have the potential to be devastating.”

Researchers tackle Zika’s unanswered questions

Youssef A. Kousa

Youssef A. Kousa, D.O., Ph.D., M.S., is examining whether interplays between certain genes make some women more vulnerable to symptomatic Zika infections.

A Maryland woman traveled to the Dominican Republic early in her pregnancy, spending three weeks with family. She felt dizzy and tired and, at first, attributed the lethargy to jet lag. Then, she experienced a rash that lasted about four days. She never saw a bite or slapped a mosquito while in the Dominican Republic but, having heard about the Zika virus, asked to be tested.

Her blood tested positive for Zika.

Why was this pregnant woman infected by Zika while others who live year-round in Zika hot zones remain free of the infectious disease? And why was she among the slim minority of Zika-positive people to show symptoms?

Youssef A. Kousa, D.O., Ph.D., M.S., a pediatric resident in the child neurology track at Children’s National Health System, is working on a research study that will examine whether interplays between certain genes make some women more vulnerable to symptomatic Zika infections during pregnancy, leaving  some fetuses at higher risk of developing microcephaly.

Dr. Kousa will present preliminary findings during Research and Education Week 2017 at Children’s National.

At sites in Puerto Rico, Colombia and Washington D.C., Dr. Kousa and his research collaborators are actively recruiting study participants and drawing blood from women whose Zika infections were confirmed in the first or second trimester of pregnancy. The blood is stored in test tubes with purple caps, a visual cue that the tube contains an additive that binds DNA, preventing it from being cut up. Additional research sites are currently being developed.

When the blood arrives at Children’s National, Dr. Kousa will use a centrifuge located in a sample preparation room to spin the samples at high speed for 11 minutes. The sample emerges from the centrifuge in three discrete layers, separated by weight. The rose-colored section that rises to the top is plasma. Plasma contains tell-tale signs of the immune system’s past battles with viruses and will be analyzed by Roberta L. DeBiasi, M.D., M.S., Chief of the Division of Pediatric Infectious Diseases at Children’s National, and Dr. Kousa’s mentor.

A slender line at the middle indicates white blood cells. The dark red layer is heavier red blood cells that sink to the bottom. This bottom half of the test tube, where the DNA resides, is where Dr. Kousa will perform his genetic research.

For years, Dr. Kousa has worked to identify genetic risk factors that influence which fetuses develop cleft lip and palate. In addition to genetic variances that drive disease, he looks at environmental overlays that can trigger genes to respond in ways that cause pediatric disease. When Zika infections raced across the globe, he says it was important to apply the same genetic analyses to the emerging disease. Genes make proteins that carry out instructions, but viral infection disrupts how genes interact, he says. Cells die. Other cells do not fully mature.

While certain poverty-stricken regions of Brazil have recorded the highest spikes in rates of microcephaly, more is at play than socioeconomics, he says. “It didn’t feel like all of the answers lie in the neighborhood. One woman with a Zika-affected child can live just down the street from a child who is more or less severely affected by Zika.”

As a father, Dr. Kousa is particularly concerned about how Zika stunts growth of the fetal brain at a time when it should expand exponentially. “I have three kids. You see them as they achieve milestones over time. It makes you happy and proud as a parent,” he says.

Sarah B. Mulkey

Sarah B. Mulkey, M.D., Ph.D., is studying whether infants exposed to Zika in utero achieve the same developmental milestones as uninfected infants.

While Dr. Kousa concentrates on Zika’s most devastating side effects, his colleague Sarah B. Mulkey, M.D., Ph.D., is exploring more subtle damage Zika can cause to fetuses exposed in utero. In the cohort of Colombian patients that Dr. Mulkey is researching, just 8 percent had abnormal fetal brain magnetic resonance images (MRIs). At first glance, the uncomplicated MRIs appear to be reassuring news for the vast majority of pregnant women.

Dr. Mulkey also will present preliminary findings during Research and Education Week 2017 at Children’s National.

In the fetus, the Zika virus makes a beeline to the developing brain where it replicates with ease and can linger after birth. “We need to be cautious about saying the fetal MRI is ‘normal’ and the infant is going to be ‘normal,’ ” Dr. Mulkey says. “We know with congenital cytomegalovirus that infected infants may not show symptoms at birth yet suffer long-term consequences, such as hearing deficits and vision loss.”

Among Zika-affected pregnancies in Colombia in which late-gestational age fetal MRIs were normal, Dr. Mulkey will use two different evaluation tools at 6 months and 1 year of age to gauge whether the babies accomplish the same milestones as peers. One evaluation tool is a questionnaire that has been validated in Spanish.

At 6 months and 1 year of age, the infants’ motor skills will be assessed, such as their ability to roll over in both directions, sit up, draw their feet toward their waist, stand, take steps independently and purposefully move their hands. Videotapes of the infants performing the motor skills will be scored by Dr. Mulkey and her mentor, Adre du Plessis, M.B.Ch.B., Chief of the Division of Fetal and Transitional Medicine at Children’s National. The Thrasher Research Fund is funding the project, “Neurologic outcomes of apparently normal newborns from Zika virus-positive pregnancies,” as part of its Early Career Award Program.

Both research projects are extensions of a larger multinational study co-led by Drs. du Plessis and DeBiasi that explores the impact of prolonged Zika viremia in pregnant women, fetuses and infants; the feasibility of using fetal MRI to describe the continuum of neurological impacts in Zika-affected pregnancies; and long-term developmental issues experienced by Zika-affected infants.

Thrasher Research Fund supports Zika virus neurologic outcomes study

The Thrasher Research Fund will fund a Children’s National project, “Neurologic Outcomes of Apparently Normal Newborns From Zika Virus-Positive Pregnancies,” as part of its Early Career Award Program, an initiative designed to support the successful training and mentoring of the next generation of pediatric researchers.

The project was submitted by Sarah B. Mulkey, M.D., Ph.D., a fetal-neonatal neurologist who is a member of the Congenital Zika Virus Program at Children’s National. During the award period, Dr. Mulkey will be mentored by Adre du Plessis, M.B.Ch.B., director of the Fetal Medicine Institute, and Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases. Drs. du Plessis and DeBiasi co-direct the multidisciplinary Zika program, one of the nation’s first.

In the award letter, the fund mentioned Children’s institutional support for Dr. Mulkey, as demonstrated by the mentors’ letter of support, as “an important consideration throughout the funding process.”

Fetal medicine update: fetal brain development, zika virus

May 2, 2016 -Impaired global and tissue-specific brain development in the growth-restricted fetus.
A team of researchers applied an advanced imaging technique, three-dimensional MRI, to study brain development in high-risk pregnancies and are the first to report regional, tissue-specific volume delays for the developing fetal brain in FGR-affected pregnancies. The team compared overall fetal brain volume as well as regional brain volumes for a control group of healthy young pregnant women with a group of young women whose pregnancies were complicated by FGR. While fetuses in both groups grew exponentially as pregnancies progressed, the researchers began to see dramatic differences when they compared the volumes of specific regions of the brain, including the cerebellum, which coordinates balance and smooth movement; the deep gray matter, which also is involved in complex functions, such as memory and emotion; and the white matter, which is made up of millions of nerve fibers that connect to neurons in different regions.

March 30, 2016Congenital Zika viral infection linked to significant fetal brain abnormalities, despite ‘normal’ ultrasounds.
Infectious Zika virus was isolated from the brain of a 21-week-old fetus after causing extensive damage to brain tissue – despite ultrasounds that showed no sign of microcephaly at weeks 13, 16, and 17, according to a report published online in The New England Journal of Medicine. “While this is a single case, it poses troubling questions that could inform future research,” says the study’s co-senior author, Adre du Plessis, M.B.Ch.B., Director of the Fetal Medicine Institute and Chief of the Fetal and Transitional Medicine Division at Children’s National Health System. “Evidence is mounting that the Zika virus can persist in pregnant women’s bloodstreams weeks after their initial infection, arguing for changes to how these pregnancies are monitored,” Dr. du Plessis said. Six of the named authors are affiliated with Children’s National, where the pregnant woman sought more thorough assessment after testing positive for the Zika virus herself following international travel.