Protecting infants
The results support “previous studies that have found that, while intrauterine transmission is possible, it is not common,” Dr. Jamieson and Dr. Rasmussen noted. “Most viral infections can be transmitted transplacentally; however, why some viruses are transmitted relatively easily across the placenta (e.g., HIV, Zika, herpes simplex virus), while others, such as influenza, are transmitted rarely is not well understood.”
Data indicate that infants are at higher risk of severe COVID-19, compared with older children. Nonetheless, research suggests that strict hygiene measures can protect infants born to mothers with SARS-CoV-2 infection, they added.
The research was supported by the National Institutes of Health; the Cystic Fibrosis Foundation; a gift from Mark, Lisa, and Enid Schwartz; and by the Massachusetts General Hospital department of pathology Vickery-Colvin Award and other nonprofit groups. Dr. Edlow, Dr. Jamieson, and Dr. Rasmussen had no conflict of interest disclosures.
The coauthors of both studies disclosed ties to pharmaceutical companies, grants from foundations and government agencies, a patent for a SARS-CoV-2 vaccine, and author royalties from publishers.