A new study led by researchers at UCLA Health finds no evidence of SARS-CoV-2 transmission through breast milk.
The authors found that while a small proportion of breast milk samples from recently infected mothers contained COVID-19 genetic material, this did not translate into the presence of infectious replicating viral particles or lead to evidence of SARS-CoV-2 infection in breastfeeding infants, according to a news release from the university.
The study was published in Pediatric Research.
The University of California researchers analyzed breast milk samples from 110 lactating women who donated to the Mommy’s Milk Human Milk Biorepository at the University of California, San Diego between March and September 2020. Of the 110 women included, 65 had a positive COVID-19 test, while nine had symptoms but tested negative, and 36 were symptomatic but were not tested.
The researchers found SARS-CoV-2 genetic material (RNA) in the breast milk of seven women (6%) with either confirmed infection or who reported being symptomatic. A second breast milk sample taken from these seven women between one and 97 days later did not contain any SARS-CoV-2 RNA. The authors did not find any SARS-CoV-2 genetic material known as SgRNA, which is an indicator of virus replication, in the seven breast milk samples and when culturing other samples. There was no clinical evidence of infection in the infants who were breastfed by the seven mothers with SARS-CoV-2 RNA in their milk.
