Mother-to-Child Transmission of SARS-CoV-2 May Be Underestimated
The rate of mother-to-child transmission of SARS-CoV-2 infection is likely higher than the current estimate of 2%-8%, suggests a recent study using cord blood serology to determine incidence. The study was presented at the annual meeting of the American Academy of Pediatrics. Cord blood screening is a potential tool to identify SARS-CoV-2 infected and/or exposed neonates who should then be followed for long-term consequences of mother-to-child transmission
@solmarie Serologic tests for congenital infections are inherently challenged by the transfer of maternal IgG across the placenta and therefore must rely on non-IgG isotype response detection, which have inherently been more susceptible to false-positive results than IgG-based tests. It is unclear if virologic testing was performed in the infants, which, if positive in the same infants for which cord blood IgM/IgA responses were identified, could further validate positive serologic findings.