Zika Virus Infection in Pregnant Women in Rio de Janeiro—Preliminary Report

Abstract

BACKGROUND Zika virus (ZIKV) has been linked to neonatal microcephaly. To characterize the spectrum of ZIKV disease in pregnancy, we followed patients in Rio de Janeiro to describe clinical manifestations in mothers and repercussions of acute ZIKV infection in fetuses. METHODS We enrolled pregnant women in whom a rash had developed within the previous 5 days and tested blood and urine specimens for ZIKV by reverse-transcriptase-polymerasechain-reaction assays. We followed the women prospectively and collected clinical and ultrasonographic data. RESULTS A total of 88 women were enrolled from September 2015 through February 2016; of these 88 women, 72 (82%) tested positive for ZIKV in blood, urine, or both. The timing of acute ZIKV infection ranged from 5 to 38 weeks of gestation. Predominant clinical features included pruritic descending macular or maculopapular rash, arthralgias, conjunctival injection, and headache; 28% had fever (short-term and low-grade). Women who were positive for ZIKV were more likely than those who were negative for the virus to have maculopapular rash (44% vs. 12%, P = 0.02), conjunctival involvement (58% vs. 13%, P = 0.002), and lymphadenopathy (40% vs. 7%, P = 0.02). Fetal ultrasonography was performed in 42 ZIKV-positive women (58%) and in all ZIKV-negative women. Fetal abnormalities were detected by Doppler ultrasonography in 12 of the 42 ZIKV-positive women (29%) and in none of the 16 ZIKV-negative women. Adverse findings included fetal deaths at 36 and 38 weeks of gestation (2 fetuses), in utero growth restriction with or without microcephaly (5 fetuses), ventricular calcifications or other central nervous system (CNS) lesions (7 fetuses), and abnormal amniotic fluid volume or cerebral or umbilical artery flow (7 fetuses). To date, 8 of the 42 women in whom fetal ultrasonography was performed have delivered their babies, and the ultrasonographic findings have been confirmed. CONCLUSIONS Despite mild clinical symptoms, ZIKV infection during pregnancy appears to be associated with grave outcomes, including fetal death, placental insufficiency, fetal growth restriction, and CNS injury.

Association between Zika virus infection and microcephaly in Brazil, January to May, 2016: preliminary report of a case-control study

“…12,33 We expect one component of the congenital Zika syndrome to be intrauterine growth restriction; we recorded a high proportion of neonates with microcephaly who were small for gestational age. Brasil and colleagues 7 reported fetal growth restriction in fetuses of mothers who had Zika virus infection during pregnancy. In June, 2016, WHO recommended the use of Intergrowth-21 Size at Birth Standards for identifying neonates with microcephaly.…”

“…5 Since the hypothesis that the microcephaly epidemic in Brazil is caused by congenital Zika virus infection was fi rst proposed, 6 there has been an accumulation of evidence supporting the association. [7][8][9][10][11][12][13][14][15][16][17] The relation between Zika virus and birth defects is strong enough to be deemed causal, but the argument would be stronger if confi rmed by at least one case-control study and a cohort study. 18 Indeed, the evidence so far comes from case reports, 16 case series, 19,20 modelling studies, 17 and the preliminary report of a cohort study.…”

“…18 Indeed, the evidence so far comes from case reports, 16 case series, 19,20 modelling studies, 17 and the preliminary report of a cohort study. 7 None of these studies included appropriate population control groups. We report the preliminary analysis of a case-control study, requested by the Brazilian Ministry of Health, to investigate the causes of the microcephaly epidemic in Brazil; the main hypothesis was that it is caused by congenital Zika virus infection.…”

Serious disease outbreaks caused by viruses transmitted by Aedes aegypti in Brazil

“…Since then, physicians and scientists from Brazil and other countries have shown that ZIKV causes a severe congenital disease by infecting the central nervous system of the fetus in all phases of pregnancy. ZIKV is a neurotropic virus, and high viral loads have been found in the nervous tissues of the stillborn children of mothers infected with ZIKV (10) . Information has been collected as fast as possible to help the management of patients, provide the guidance to women in childbearing age and pregnancy, and to control the outbreaks.…”

Zika virus and global health security

“…6 Recent studies suggest that Zika virus infection can cause severe joint damage and genitourinary, cardiac, and digestive complications among aff ected infants. 7 Many could be impaired in less obvious ways, with disabilities appearing later in a child's development.…”