JAMA: Birth Defects Among Fetuses and Infants of US Women With Evidence of Possible Zika Virus Infection During Pregnancy

[tetano]

Original Investigation

December 15, 2016
Birth Defects Among Fetuses and Infants of US Women With Evidence of Possible Zika Virus Infection During Pregnancy

Margaret A. Honein, PhD¹; April L. Dawson, MPH¹; Emily E. Petersen, MD¹; et al Abbey M. Jones, MPH¹; Ellen H. Lee, MD²; Mahsa M. Yazdy, PhD³; Nina Ahmad, MD⁴; Jennifer Macdonald, MPH⁵; Nicole Evert, MS⁶; Andrea Bingham, PhD⁷; Sascha R. Ellington, MSPH¹; Carrie K. Shapiro-Mendoza, PhD¹; Titilope Oduyebo, MD¹; Anne D. Fine, MD²; Catherine M. Brown, DVM³; Jamie N. Sommer, MS⁴; Jyoti Gupta, MPH⁵; Philip Cavicchia, PhD⁷; Sally Slavinski, DVM²; Jennifer L. White, MPH⁴; S. Michele Owen, PhD¹; Lyle R. Petersen, MD¹; Coleen Boyle, PhD¹; Dana Meaney-Delman, MD¹; Denise J. Jamieson, MD¹; for the US Zika Pregnancy Registry Collaboration
Author Affiliations Article Information
JAMA. Published online December 15, 2016. doi:10.1001/jama.2016.19006

editorial comment icon Editorial Comment

• Editorial
  Preliminary Results From the US Zika Pregnancy Registry
  William J. Muller, MD, PhD; Emily S. Miller, MD, MPH

Key Points

Question What proportion of fetuses and infants of women in the United States with laboratory evidence of possible Zika virus infection during pregnancy have birth defects?
Findings Based on preliminary data from the US Zika Pregnancy Registry, among 442 completed pregnancies, 6% overall had a fetus or infant with evidence of a Zika virus?related birth defect, primarily microcephaly with brain abnormalities, whereas among women with possible Zika virus infection during the first trimester, 11% had a fetus or infant with a birth defect.
Meaning These findings support the importance of screening pregnant women for Zika virus exposure.
Abstract

Importance Understanding the risk of birth defects associated with Zika virus infection during pregnancy may help guide communication, prevention, and planning efforts. In the absence of Zika virus, microcephaly occurs in approximately 7 per 10 000 live births.
Objective To estimate the preliminary proportion of fetuses or infants with birth defects after maternal Zika virus infection by trimester of infection and maternal symptoms.
Design, Setting, and Participants Completed pregnancies with maternal, fetal, or infant laboratory evidence of possible recent Zika virus infection and outcomes reported in the continental United States and Hawaii from January 15 to September 22, 2016, in the US Zika Pregnancy Registry, a collaboration between the CDC and state and local health departments.
Exposures Laboratory evidence of possible recent Zika virus infection in a maternal, placental, fetal, or infant sample.
Main Outcomes and Measures Birth defects potentially Zika associated: brain abnormalities with or without microcephaly, neural tube defects and other early brain malformations, eye abnormalities, and other central nervous system consequences.
Results Among 442 completed pregnancies in women (median age, 28 years; range, 15-50 years) with laboratory evidence of possible recent Zika virus infection, birth defects potentially related to Zika virus were identified in 26 (6%; 95% CI, 4%-8%) fetuses or infants. There were 21 infants with birth defects among 395 live births and 5 fetuses with birth defects among 47 pregnancy losses. Birth defects were reported for 16 of 271 (6%; 95% CI, 4%-9%) pregnant asymptomatic women and 10 of 167 (6%; 95% CI, 3%-11%) symptomatic pregnant women. Of the 26 affected fetuses or infants, 4 had microcephaly and no reported neuroimaging, 14 had microcephaly and brain abnormalities, and 4 had brain abnormalities without microcephaly; reported brain abnormalities included intracranial calcifications, corpus callosum abnormalities, abnormal cortical formation, cerebral atrophy, ventriculomegaly, hydrocephaly, and cerebellar abnormalities. Infants with microcephaly (18/442) represent 4% of completed pregnancies. Birth defects were reported in 9 of 85 (11%; 95% CI, 6%-19%) completed pregnancies with maternal symptoms or exposure exclusively in the first trimester (or first trimester and periconceptional period), with no reports of birth defects among fetuses or infants with prenatal exposure to Zika virus infection only in the second or third trimesters.
Conclusions and Relevance Among pregnant women in the United States with completed pregnancies and laboratory evidence of possible recent Zika infection, 6% of fetuses or infants had evidence of Zika-associated birth defects, primarily brain abnormalities and microcephaly, whereas among women with first-trimester Zika infection, 11% of fetuses or infants had evidence of Zika-associated birth defects. These findings support the importance of screening pregnant women for Zika virus exposure.


full article

http://jamanetwork.com/journals/jama/fullarticle/2593702?utm_source=Silverchair_Information_Systems&utm_campaign=FTM_12132016&utm_content=news_releases&cmp=1&utm_medium=email

[tetano]

Editorial

December 15, 2016
Preliminary Results From the US Zika Pregnancy Registry
Untangling Risks for Congenital Anomalies

Human illness caused by Zika virus infection has been described for several decades, but this pathogen was in a sense better classified as an infectious diseases “trivia question” before reports of larger outbreaks appeared within the last 10 years.¹ Nonspecific symptoms of viral infection, including fever, rash, arthralgia, and conjunctivitis, have been described for Zika infection, and asymptomatic infection is fairly common.¹ However, now that strong and accumulating evidence has implicated Zika infection during pregnancy in severe central nervous system sequelae after infection of the fetus,^2,3 there has been increased urgency in acquiring a greater understanding of the pathophysiology of Zika disease, and efforts to control the spread of this virus have escalated.
Among the many unanswered questions associated with Zika virus infection during pregnancy is whether the risk of congenital abnormalities is influenced by the gestational timing of maternal infection (early vs late). There is precedence with other congenital infections to anticipate that infection early in pregnancy will lead to greater risk of severe adverse neurodevelopmental outcomes. Congenital rubella syndrome, characterized by a variety of clinical features, including central nervous system, ocular, auditory, and cardiac effects, is well described as having a substantially increased risk of fetal infection when maternal infection is acquired early in pregnancy, with few clinical manifestations when maternal infection occurs after 20 weeks’ gestation.⁴ For cytomegalovirus, primary maternal infection is less likely to transmit the virus to the fetus early in pregnancy. However, if fetal infection does occur, the risk of severe, often neurologic birth defects is higher when transmission occurs earlier in pregnancy.⁵ Whether the timing of infection affects the risk of congenital abnormalities is critically important for families, physicians, and the development of public health approaches to screening.

..


http://jamanetwork.com/journals/jama...rticle/2593701

[Pathfinder]

CDC Releases Preliminary Estimates of Birth Defects Following Zika Virus Infection in Pregnancy

Press Release

Embargoed until: Thursday, December 15, 2016, 11:00 AM EST
Contact: Media Relations
(404) 639-3286

In a new report published in the Journal of the American Medical Association, CDC scientists used preliminary data from the US Zika Pregnancy Registry (USZPR) to estimate that 6 percent of completed pregnancies following Zika virus infection were affected by one or more birth defects potentially related to Zika virus infection during pregnancy. The report combined data from the continental United States and Hawaii that were collected in collaboration between CDC and state and local health departments to monitor pregnancies with laboratory evidence of Zika virus infection.

As of September 22, 2016, 442 women with possible Zika virus infection in the USZPR had completed their pregnancies. Twenty-six of the completed pregnancies, or 6 percent, were reported to have one or more of the birth defects potentially related to Zika virus infection during pregnancy. Among women infected with Zika in the first trimester of pregnancy, 11 percent were reported to have fetuses or infants with birth defects, which is consistent with previous modeling estimates. The proportion of pregnancies with birth defects was similar for pregnant women who did or who did not experience symptoms, about 6 percent in each group. The 18 infants with a finding of microcephaly represent 4 percent (18/442) of the completed pregnancies; this prevalence is substantially higher than the background prevalence of microcephaly in the United States of about 7 per 10,000 live births, or about 0.07 percent of live births.

The 26 birth defects occurred among fetuses/infants of pregnant women who were exposed to Zika virus during their pregnancies in the following locations with active Zika virus transmission: Barbados, Belize, Brazil, Colombia, Dominican Republic, El Salvador, Guatemala, Haiti, Honduras, Mexico, Republic of Marshall Islands, and Venezuela.

“This is an important study. It shows that the rate of microcephaly and other fetal malformations related to Zika is similar among babies born in the United States – whose mothers were infected during travel to a dozen countries with active Zika transmission – to the estimated rate in Brazil,” said CDC Director Tom Frieden, M.D. M.P.H.. “Zika poses a real risk throughout pregnancy, but especially in the first trimester; it’s critical that pregnant women not travel to areas where Zika is spreading.”

These estimates should be considered in the context of a recent report of infants in Brazil with congenital Zika virus infection who appeared healthy at birth, but later experienced slowed head growth and microcephaly. Given these recent findings from Brazil, it is possible that a greater proportion of the infants in this report could be affected by a Zika-related birth defect within the first year of life.

Prevention of Zika virus infection during pregnancy is critically important given the severity of its associated birth defects and the preliminary estimates outlined in this report. This report highlights the importance of CDC guidance to test all pregnant women with possible exposure to Zika virus regardless of whether they had symptoms of Zika, and to test infants born to mothers with possible Zika virus infection.

CDC guidance for pregnant women and women considering pregnancy

CDC continues to recommend that pregnant women not travel to areas with Zika. If a pregnant woman travels to or lives in an area with active Zika virus transmission, she should talk with her healthcare provider and strictly follow steps to prevent mosquito bites and sexual transmission of Zika virus. For more information, please visit www.cdc.gov/zika/pregnancy/.

CDC continues to encourage women considering pregnancy and their partners in areas with active Zika transmission to talk to their healthcare providers about pregnancy planning so that they know the risks and the ways to reduce them. For more information: www.cdc.gov/zika/pregnancy/thinking-about-pregnancy.html.

###
U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

CDC works 24/7 saving lives and protecting people from health threats to have a more secure nation. Whether these threats are chronic or acute, manmade or natural, human error or deliberate attack, global or domestic, CDC is the U.S. health protection agency.

• Page last reviewed: December 15, 2016
• Page last updated: December 15, 2016

https://www.cdc.gov/media/releases/2016/p1215-birth-defects-zika.html