Risk of Vertical Transmission of Human Parvovirus B19 Among Pregnant Women Attending Antenatal Clinics in North-Central Nigeria

Abstract

Background: Human Parvovirus B19 (B19V) is a significant cause of foetal morbidity and mortality due to its ability to cross the placenta during maternal viraemia. Despite documented high seroprevalence in Nigeria, data on the molecular evidence of vertical transmission risk among pregnant women are limited. Objective: To determine the seroprevalence, DNA detection rate, and associated risk factors for vertical transmission of B19V among pregnant women attending antenatal clinics in North Central Nigeria. Methods: A cross-sectional study was conducted between 2018 and 2022 involving 276 pregnant women recruited from antenatal clinics of three tertiary health centres in Benue, Kogi and Plateau States, North-Central Nigeria. Demographic and clinical data were collected using a structured questionnaire. Participants’ blood samples were analysed for anti-B19V IgG and IgM antibodies using ELISA. A subset of 38 serologically reactive samples was tested for B19V DNA using quantitative polymerase chain reaction. Statistical associations were analysed using SPSS (v26.0) at 95% confidence level. Results: Anti-B19V IgG and IgM antibodies were detected in 12.7% and 7.7% of the pregnant women, respectively. B19V DNA was detected in 55.3% (21/38) of the sero-reactive pregnant women subset across all trimesters. Detection rate was highest in the second trimester. Tribe was marginally associated with both seroprevalence and DNA positivity; and between the number of previous pregnancies and IgG positivity. Conclusion: This study reports serological and molecular evidence of B19V viraemia among pregnant women in North Central Nigeria, with DNA positivity suggesting risk of vertical transmission. Screening for B19V in antenatal care is recommended to prevent adverse foetal outcomes.