A systematic review of vertical transmission and antibodies against SARS-CoV-2 among infants born to mothers with COVID-19

Abstract Amidst the Coronavirus Disease 2019 (COVID-19) pandemic, evidence on vertical transmission and natural passive immunity among the newborns exposed to COVID-19 is scanty and varies. This pose a challenge on preventive interventions for the newborns. We conducted a systematic review to first, determine the likelihood of vertical transmission among COVID-19 exposed infants and second, determine whether antibodies against Severe Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)/ COVID-19 virus exist among COVID-19 vertically exposed but negative infants. This review registered in PROSPERO searched evidence from PubMed/ MEDLINE and Google Scholar, among others. About 517 studies were retrieved, where only 33 articles (5.8%) qualified for final analysis. A total of 205 infants born to SARS-CoV-2 positive mothers were pooled from 33 eligible studies. Overall, 6.3% (13/205; 95%CI: 3.0%-9.7%) of the infants tested positive for COVID-19 virus at birth. Of 33 eligible studies, 6 studies (18.8%) reported about IgG/IgM against SARS-CoV-2. Anti-SARS-CoV-2 IgG/IgM were detected in 90% (10/11; 95%CI: 73.9%-107.9%) of infants who had no COVID-19 but vertically exposed. In conclusion, the current evidence revealed a low possibility of vertical transmission of COVID-19 while antibodies against SARS-CoV-2 were detected in most of the infants who had no COVID-19. Further studies on perinatal outcomes and the magnitude of natural passive immunity in infants born to mothers with COVID-19 are warranted.