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Dengue virus

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.

Deer tick

Lyme disease: When will pediatric symptoms resolve?

Deer tick

Over a 13-year period that began in 2004, cases of illness transmitted by ticks, mosquitoes and fleas have more than tripled, the CDC found.

The summer of 2018 was a bad summer for Lyme disease, the tick-borne disease that was first documented in the 1970s in the town of Lyme, Connecticut. While about 30,000 cases of this disease had been reported annually in recent years, studies suggest that the actual number of infections is around 10 times greater.

And according to a study published May 2018 by the Centers for Disease Control and Prevention (CDC), those case numbers may increase over time. Over a 13-year period that began in 2004, cases of illness transmitted by ticks, mosquitoes and fleas have more than tripled, the CDC found.

Lyme disease causes a host of uncomfortable symptoms, ranging from headache and neurological problems, heart problems and eye inflammation in earlier stages, and progressing to joint pain and arthritis in later stages. While it can be treated successfully with appropriate antibiotics, the timeframe for kids’ symptom resolution has been unclear.

A new study by researchers at Children’s National Health System shows that symptoms improve just days or weeks after starting antibiotic therapy for the vast majority of patients, with people whose symptoms had been present a briefer time improving the fastest.

“These findings offer a reassuring timeline for doctors, patients and their families about when patients with Lyme disease can expect to feel better,” says study Senior Author Roberta L. DeBiasi, M.D., MS, Children’s National’s chief of the Division of Pediatric Infectious Diseases and co-director of the Congenital Zika Virus Program. Dr. DeBiasi was recently appointed to serve on a 52-member Tick-Borne Disease Working Group established in 2018 by the Department of Health and Human Services.

Dr. DeBiasi and colleagues collected data retrospectively from the medical records of 78 patients who had been hospitalized at Children’s National for Lyme disease from 2008 to 2015. Each child, who was younger than 18 years old, had documented symptoms and lab tests conclusive for this disease.

Just under one-half had symptoms consistent with early-stage disease, such as:

  • A severe headache
  • Meningitis (inflammation of the membranes covering the brain)
  • Cranial nerve palsy (a nerve dysfunction that affects eye movement and can cause double vision)
  • Multiple erythema migrans rashes (the bulls-eye-shaped rash that’s a hallmark of Lyme disease) and
  • Pseudotumor cerebri (increased pressure inside the skull).

Just over one-half had symptoms consistent with late-stage disease, which mostly consisted of arthritis affecting the knees, along with the hips and elbows in some cases.

In the hospital, each patient was started on an antibiotic that can effectively treat Lyme, including doxycycline, cefotaxime or ceftriaxone, which they continued at home for the prescribed length of the course. The researchers then tracked how quickly the patients’ symptoms resolved.

They report online July 30, 2018, in the Journal of the Pediatric Infectious Diseases Society, that the time to symptom resolution for early stages of disease did not depend on the duration of symptoms prior to starting antibiotics. However, for later stages of disease, patients with longer duration of symptoms prior to starting treatment took longer for their symptoms to resolve.

For patients with early-stage disease, the most common symptom was headache; the median time to symptom resolution was just three days, no matter how long the headache had persisted before treatment started. However, for patients with late-stage Lyme disease, the median time to resolution was 18 days. However, the time depended largely on how long symptoms had persisted before patients began taking antibiotics. For example, patients who had experienced arthritis for less than one week had a shorter time to resolution than those who had arthritis for more than two weeks.

This finding is important, Dr. DeBiasi says, because it suggests that diagnosing Lyme disease earlier – and prescribing the appropriate therapy as soon as possible – can hasten recovery. The vast majority of patients in the study, she adds, eventually experienced full resolution of their symptoms, which should be comforting to families worried about whether their child will ever feel well again.

“We all want what patients and their families want: to feel better as quickly as possible,” Dr. DeBiasi says. “This study gives us valuable information about how soon that will happen given the duration of pediatric patients’ symptoms.”

Dr. DeBiasi and Children’s Psychologist Maureen Monaghan, Ph.D., are leading another Lyme study in collaboration with the National Institutes of Health/National Institute of Allergy and Infectious Diseases to evaluate symptom resolution, quality of life and neurocognitive outcomes in a larger group of pediatric patients with Lyme disease.

In addition to Dr. DeBiasi and Monaghan, Children’s co-authors include Lead Author Mattia E. Chason; Biostatistician Jichuan Wang, Ph.D.; and Yao Cheng.

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.”

zika virus

Will the Zika epidemic re-emerge in 2017?

Anthony Fauci

Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, discussed the possibility of a reemergence of Zika virus at Children’s National Research and Education Week.

Temperatures are rising, swelling the population of Aedes mosquitoes that transmit the Zika virus and prompting an anxious question: Will the Zika epidemic re-emerge in 2017?

Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health (NIH), sketched out contrasting scenarios. Last year in Puerto Rico, at least 13 percent of residents were infected with Zika, “a huge percentage of the population to get infected in any one outbreak,” Dr. Fauci says. But he quickly adds: “That means that 87 percent of the population” did not get infected. When the chikungunya virus swept through the Caribbean during an earlier outbreak, it did so in multiple waves. “We are bracing for a return of Zika, but we shall see what happens.” Dr. Fauci says.

When it comes to the continental United States, however, previous dengue and chikungunya outbreaks were limited to southern Florida and Texas towns straddling the Mexican border. Domestic Zika transmission last year behaved in much the same fashion.

“Do we think we’re going to get an outbreak [of Zika] that is disseminated throughout the country? The answer is no,” Dr. Fauci adds. “We’re not going to see a major Puerto Rico-type outbreak in the continental United States.”

Dr. Fauci’s remarks were delivered April 24 to a standing-room-only auditorium as part of Research and Education Week, an annual celebration of the cutting-edge research and innovation happening every day at Children’s National. He offered a sweeping, fact-filled summary of Zika’s march across the globe: The virus was first isolated from a primate placed in a treehouse within Uganda’s Zika forest to intentionally become infected; Zika lurked under the radar for the first few decades, causing non-descript febrile illness; it bounced from country to country, causing isolated outbreaks; then, it transformed into an infectious disease of international concern when congenital Zika infection was linked to severe neural consequences for babies born in Brazil.

zika virus

Zika virus lurked under the radar for several decades, causing non-descript febrile illness; it bounced from country to country, resulting in isolated outbreaks; then, it transformed into an infectious disease of international concern.

“I refer to Brazil and Zika as the perfect storm,” Dr. Fauci told attendees. “You have a country that is a large country with a lot of people, some pockets of poverty and economic depression –  such as in the northeastern states –  without good health care there, plenty of Aedes aegypti mosquitoes and, importantly, a totally immunologically naive population. They had never seen Zika before. The right mosquitoes. The right climate. The right people. The right immunological status. And then, you have the explosion in Brazil.”

In Brazil, 139 to 175 babies were born each year with microcephaly – a condition characterized by a smaller than normal skull – from 2010 to 2014. From 2015 through 2016, that sobering statistic soared to 5,549 microcephaly cases, 2,366 of them lab-confirmed as caused by Zika.

Microcephaly “was the showstopper that changed everything,” says Dr. Fauci. “All of a sudden, [Zika] went from a relatively trivial disease to a disease that had dire consequences if a mother was infected, particularly during the first trimester.”

As Zika infections soared, ultimately affecting more than 60 countries, the virus surprised researchers and clinicians a number of times, by:

  • Being spread via sex
  • Being transmitted via blood transfusion, a finding from Brazil that prompted the Food and Drug Administration to recommend testing for all U.S. donated blood and blood products
  • Decimating developing babies’ neural stem cells and causing a constellation of congenital abnormalities, including vision problems and contractions to surviving infants’ arms and legs
  • Causing Guillain-Barré syndrome
  • Triggering transient hearing loss
  • Causing myocarditis, heart failure and arrhythmias

When it comes to the U.S. national response, Dr. Fauci says one of the most crucial variables is how quickly a vaccine becomes available to respond to the emerging outbreak. For Zika, the research community was able to sequence the virus and launch a Phase I trial in about three months, “the quickest time frame from identification to trial in the history of all vaccinology,” he adds.

Zika is a single-stranded, enveloped RNA virus that is closely related to dengue, West Nile, Japanese encephalitis and Yellow fever viruses, which gives the NIH and others racing to produce a Zika vaccine a leg up. The Yellow fever vaccine, at 99 percent effectiveness, is one of the world’s most effective vaccines.

“I think we will wind up with an effective vaccine. I don’t want to be over confident,” Dr. Fauci  says. “The reason I say I believe that we will is because [Zika is] a flavivirus, and we have been able to develop effective flavivirus vaccines. Remember, Yellow fever is not too different from Zika.”