Vertical Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 From the Mother to the Infant

To the Editor During the 2019 coronavirus disease (COVID-19) pandemic, a small number of affected pregnant women has been reported, and mother-to-child transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been questioned. The first report reassured about the lack of vertical transmission in 9 COVID-19–affected mothers,¹ reporting the absence of SARS-CoV-2 in amniotic fluid, breast milk, cord blood, and neonatal throat swab. Noteworthy, Dong et al² hypothesized that SARS-CoV-2 can be transmitted in utero, reporting the case of a newborn girl with IgM antibodies to SARS-CoV-2, an elevated cytokines profile (interleukin 6 and interleukin 10), and modest alteration of liver markers 2 hours after birth. However, the authors had difficulty explaining the negative results of a SARS-CoV-2 RNA test of the infant’s nasopharyngeal swabs repeatedly performed at 3, 6, 9, 14, and 17 days of life.