There is a dearth of data available on neonatal infection with COVID-19, limited to some case reports and case series. In one review, the authors could found 179 cases of newborns born to pregnant women infected in the third trimester of pregnancy, and getting tested for COVID-19 at birth [5]. These mothers were infected in late pregnancy, and the mean (range) time between delivery and infection was 3 (0 to 25) days. RT-PCRs performed on cord blood and amniotic fluid were negative. However, COVID-19 was detected in naso-pharyngeal samples from 6 of 179 newborns at 16 hrs of life (n = 1), 36 hrs of life (n = 2), and 48 hrs of life (n = 3). As a result, it is difficult to determine the timing of transmission in them. However, the following possibilities are plausible: droplet inhalation or contact by infected parents or health-care professionals (transmission at birth), or via breast-feeding. But, the newborns were delivered by cesarean section, immediately separated from their mothers, and placed in isolation. These steps taken in the hospital makes the transmission from the mother unlikely. In addition, breast-milk has not been shown to transmit COVID-19 till date [10]. So, a vertical (transplacental/in-utero) transmission still remains a possibility that cannot be excluded completely [11]. In the index case also, the mother was infected in third trimester, the time between infection and delivery was 3 days, the newborn was delivered by cesarean section, and immediately shifted to ICU without getting contact with the mother.
There have been no clear criteria of what actually defines a congenital COVID-19 infection. In one study, the authors described 3 newborns with positive antibodies (IgM and IgG) at birth who were born to mothers with COVID-19 infection [7,8]. Whether, these cases fit into congenital COVID-19 due to vertical transmission is debated though IgM antibody is of fetal origin (as it can not cross placenta in contrast to IgG antibody) [5]. In a cohort study of 33 newborns, 3 were having severe pneumonia, and found to be positive for COVID-19 RT-PCR of naso-pharyngeal and anal swab samples, on day 2 and day 4 of life [8]. The authors were sceptical about the possibility of peri-natal or post-natal transmission, as these newborns were born by cesarean section like in the index case, and separated from mothers from birth. But the index case in this report was positive at 12 hours of life without severe COVID-19 infection or COVID-19 pneumonia, and is stable currently. It has been described that, maternal COVID-19 infection can cause premature deliveries, respiratory distress at birth, and even intra-uterine fetal death [3,5]. All these could be secondary to the effct of severe hypoxemia resulting from COVID-19 pneumonia in the mother. In the index case decreased fetal movement and resulting birth asphyxia could be due to these factors, as mother had severe COVID-19 pneumonia with underlying HELLP syndrome. Our report has some limitations. We did not evaluate the presence of virus in amniotic fluid, cord blood, or placental tissue that could further clarify pathogenesis, and no antobody testing was done in the newborn.