Prevalence and incidence of dengue virus and antibody placental transfer during late pregnancy in central Brazil

Abstract

BackgroundMaternal dengue antibodies are considered to play a significant role in dengue pathogenesis among infants. Determining the transplacental specific antibody transfer is invaluable for establishing the optimal vaccination age among infants in endemic regions.MethodsWe conducted a cross-sectional study among pairs of maternal and corresponding umbilical cord blood samples in public hospitals. The prevalence and incidence of dengue infection were determined in 505 pairs of pregnant women and neonates during a large outbreak (2009–2010) in central Brazil. The women were interviewed at late pregnancy to assess current or past symptoms of dengue. All parturients and their neonates were screened using Dengue IgG Indirect ELISA (Panbio) to assess previous dengue exposure. A semi-quantitative measurement of the IgG antibody expressed by the index ratio was calculated using optical density (OD) values according to the manufacturer’s instructions. The studied population of parturients and their offspring was also screened for recent dengue infection by the Dengue IgM-capture ELISA (Panbio). Those participants with history of fever and two or more symptoms of dengue at least 10 days before the delivery were also tested for the dengue NS1 antigen using the Dengue Early ELISA (Panbio) and RT-PCR.ResultsThe mean maternal age was 25.8 (SD = 6.4), and 83.6% of deliveries were between 37 and 41 weeks. Approximately half of the 505 women and neonates were IgG-seropositive, yielding 99.3% co-positive mother-child frequency of antibody transfer (Kappa = 0.96). The incidence of dengue infection was 2.8% (95% CI 1.4–4.4%) among the women considering 14 IgM-positive results and one DENV2 detected by RT-PCR. The dengue NS1 antigen was undetectable in the matched pairs.ConclusionThis study provides critical data on the prevalence of transplacental transferred maternal-infant anti-dengue antibodies and incidence of infection. The design of future vaccine trials should consider diverse regional epidemiological scenarios.

Chikungunya and dengue virus infections during pregnancy: seroprevalence, seroincidence and maternal–fetal transmission, southern Thailand, 2009–2010

“…We also found a high seroprevalence of DENV infection (90•3%), a rate similar to a previous study from Bangkok, Thailand (96•9%) [13]. However, the seroprevalence of DENV in pregnant women in other countries has been found in previous studies to range from 17% to 53% [20,29]. These findings suggest that most adult Thais have had DENV infection at some point in their lives and the 2008-2009 CHIKV outbreak did not correspond to an epidemic upsurge of DENV infection.…”

Dengue virus antibodies enhance Zika virus infection

“…A recent serological survey of women giving birth in 2009–2010 in central Brazil documented that 53% of the new mothers were IgG positive for DENV. 45 ZIKV enhancement has been previously described to occur in the presence of cross-reactive sera raised against other flaviviruses. Here we demonstrate that broadly neutralizing anti-DENV E protein fusion loop HMAbs cross-react with ZIKV, do not neutralize ZIKV, and greatly enhance the replication of viral RNA and the production of viral progeny of ZIKV in cultured FcRII-positive cells.…”

Dengue Virus Antibodies Enhance Zika Virus Infection

“…The present scenario of ZIKV introduction and spread in the Pacific and the Americas is complicated by pre-existing immunity to DENV. A recent serological survey of women giving birth in 2009-2010 in central Brazil documented that 53% of the new mothers were IgG positive for DENV [49]. ZIKV enhancement has been previously described to occur in the presence of cross-reactive sera raised against other flaviviruses.…”