Section 2.2: Congenital and perinatal infections with coronaviruses other than SARS-CoV-2 (from DOI: 10.1016/j.jcv.2020.104372)
From publication: "SARS-CoV-2: Is it the newest spark in the TORCH?" published as J. Clin. Virol.; 2020 Apr 14 ; 127 104372. DOI: https://doi.org/10.1016/j.jcv.2020.104372
There has been limited evaluation of the potential for maternal-fetal transmission of coronaviruses before the current pandemic. In one prospective pilot study of the minimally pathogenic coronavirus strains 229E, OC-43, NL-63, and HKU1, vertical transmission was studied in 159 samples from maternal-infant pairs. Coronavirus was detected in seven mother-infant dyads, including in newborn gastric aspirates, and the authors concluded that vertical transmission was possible and required larger-scale investigation.
During the SARS coronavirus epidemic of 2002-2003, infection during pregnancy was associated with severe maternal illness, maternal death, and risk of spontaneous abortion. Over 100 pregnant women were identified during the SARS outbreak, and these pregnancy outcomes are the subject of a recent review. Notably, two infants with intrauterine growth restriction (IUGR) were described in one study, but no evidence of neonatal infection was observed in the 14 newborns who had virologic evaluations performed in the various cases series reported in the literature. In one study of placentas from pregnancies complicated by maternal SARS-CoV-1 infection, the most severe abnormalities observed included extensive fetal thrombotic vasculopathy and areas of avascular chorionic villi. These were interpreted as chronic findings associated with fetal vascular malperfusion and were noted in pregnancies complicated by oligohydramnios in which fetal IUGR developed. However, no signs of SARS-CoV-1 RNA or viral cytopathic effects were described in this case series.
There is limited information regarding fetal and neonatal outcomes in the setting of MERS-CoV infection. Only 13 cases of MERS infection in pregnant women appear to be reported. The fetal mortality rate was described to be 27 %. In the majority of these cases, no virological investigation of the fetus/infant was performed. The one exception (and the only evidence of MERS in pregnancy described outside of the Middle East) was a case reported from South Korea. In this case, a healthy infant was delivered, and although no testing for viral RNA was reported, the infant's blood did not contain any IgG, IgM, or IgA antibodies to MERS-CoV. Rasmussen et al. reported on a published case from the Philippines but this was in a healthcare worker from Saudi Arabia and she recovered. No comments about the pregnancy outcome were reported.
