Serological Evidence of Flavivirus Infection Among Mothers of Newborns in El Paso, Texas.

Abstract

Background: Flaviviruses represent a significant worldwide threat to human health and have the potential to emerge and cause outbreaks in non-endemic geographical regions. Ongoing surveillance for these viruses in the United States-Mexican border communities such as El Paso, Texas, is lacking. As a continuing effort to better understand the prevalence and to determine which arboviruses are endemic, the aim of this study was to determine the prevalence rate of specific flavivirus antibody among 910 human umbilical cord blood samples obtained from mothers who delivered newborns in El Paso, Texas. Materials and Methods: The samples were screened for West Nile virus (WNV) and dengue virus (DENV) IgG antibodies with an enzyme-linked immunosorbent assay and confirmed by a plaque reduction neutralization test for DENV, WNV, Zika virus (ZIKV) and Saint Louis encephalitis virus (SLEV). Results: Among the 910 samples, 2% were positive for specific IgG antibody to DENV, 4.4% to WNV, 0.1% to SLEV, and 0.0% for ZIKV antibody. The results confirmed the local transmission of WNV and supported a low prevalence rate for DENV, and this was the first reported serological evidence of SLEV infection in the El Paso community. Conclusion: The interpretation of the public health significance of these observations supported previous findings of ongoing transmission of WNV and suggested the possibility of DENV transmission and re-emergence of SLEV in the community. Therefore, prospective studies are needed to obtain a more conclusive understanding of the prevalence of flaviviruses in the El Paso community.