958. Zika Virus Infection and Pregnancy Outcomes in Puerto Rico
Session: Oral Abstract Session: Pediatric Epidemiology: Outbreaks and Surveillance
Friday, October 28, 2016: 11:30 AM
Room: 288-290
Background: An increase in infants born with microcephaly in Zika-affected areas of Brazil was reported in October 2015. The first locally acquired case of Zika virus (ZIKV) in Puerto Rico (PR) was identified in December 2015. Enhanced surveillance was established to monitor ZIKV infection in pregnant women in PR. We describe preliminary findings of ZIKV infection in pregnant women and pregnancy outcomes.

Methods: All pregnant women in PR have access to diagnostic testing for ZIKV infection. Serum specimens from women reporting acute illness are tested by RT-PCR and/or anti-Zika virus IgM ELISA based on collection date in relation to illness onset. Serum from asymptomatic pregnant women is tested by anti-Zika virus IgM ELISA. Pregnant women with laboratory evidence of ZIKV infection are monitored for adverse pregnancy outcomes. Liveborn infants/fetal deaths were also evaluated for ZIKV when the mother was not previously tested.


Through May 11, 2016, a total of 4,426 pregnant women were tested for ZIKV infection, and 122 (2.8%) tested positive. Among 998 symptomatic women tested, 83 (8.3%) were positive (11 by antibodies and 72 by viral RNA) and among 3,428 asymptomatic women tested, 39 (1.1%) were presumptive positive. Sonographic evaluations and outcomes of pregnancy are being captured for diagnosed ZIKV infected pregnant women throughout gestation. To date, 16 ZIKV infected pregnant women, all diagnosed after 26 weeks gestation, have given birth. All were live births with no reported birth defects. Nine of 16 newborns were tested for ZIKV infection and all had negative test results.

Histopathological examination of brain of one fetal loss with evidence of microcephaly in utero showed diffuse gliosis with marked calcification, and immunohistochemical, molecular and electron microscope evidence of ZIKV infection. The mother had an illness with rash during her first trimester and 12 weeks prior to pregnancy loss, however, Zika virus diagnostic testing was not performed. Serum collected at the time of pregnancy loss was negative for ZIKV by RT-PCR and IgM ELISA.


To further characterize the effects of ZIKV infection during pregnancy, heightened surveillance of pregnant women is critical, as ZIKV transmission increases throughout PR.

Janice Perez-Padilla, RN, MPH, Dengue Branch, Centers for Disease Control and Prevention, San Juan, PR


J. Perez-Padilla, None

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