Preliminary research shows SARS-CoV-2 antibodies new moms' early breastmilk

AMHERST, Mass. – Antibodies to the SARS-CoV-2 coronavirus were detected in colostrum, which is early breastmilk, from 14 of 15 women who had tested positive for COVID-19 before giving birth, according to preliminary findings from research led by a University of Massachusetts Amherst breast cancer researcher and a University of Massachusetts Medical School obstetrician-gynecologist.

As the team of UMass Amherst scientists continues related research, the early data on colostrum, the nutrient- and antibody-rich breastmilk produced in the first few days after childbirth, is available on medRxiv, the health sciences preprint server for research not yet peer-reviewed.

“Importantly this immune response was detected in colostrum of women who had their first positive test and symptoms more than four months before delivery, as well as those who had their first positive test at delivery and were asymptomatic,” writes lead author Vignesh Narayanaswamy, a UMass Amherst PhD candidate, in the preprint. He works in the breastmilk research lab of senior and corresponding author Kathleen Arcaro, professor of environmental toxicology in the Department of Veterinary and Animal Sciences.

In addition to the presence of SARS-CoV-2-specific antibodies, the research also revealed increased levels of nine cytokines associated with a COVID-19 inflammatory response.

Breastfeeding by women infected with SARS-CoV-2 is endorsed by the World Health Organization and the Centers for Disease Control and Prevention, and available evidence suggests breastmilk rarely contains live coronavirus and is not likely to spread the disease to babies.

The extent to which the COVID-19 antibodies found in colostrum provide immunity to babies is not yet clear, but a first important step was determining the presence of antibodies. “Breastmilk is super beneficial, we know that. Now we’ll be looking at the ability of these antibodies to neutralize the virus,” Arcaro says.

In her lab, Arcaro studies breastmilk to understand how hereditary BRCA breast cancer develops and how to prevent it. Like many scientists worldwide, Arcaro moved quickly to apply her research expertise to fight the pandemic, funded only with a small seed grant from UMass Amherst.

In the COVID-19 colostrum study, she partnered with Dr. Heidi Leftwich at UMass Memorial Medical Center in Worcester. The study participants hand-expressed colostrum samples from each breast onto spot cards on the day of, or the day after, giving birth. Within two more days, six of the participants also provided liquid bilateral colostrum samples in small containers. The controls for the study were colostrum samples collected from eight women between 2011-2013.

The analysis to detect antibodies specific to the SARS-CoV-2 virus was conducted using an enzyme-linked immunosorbent assay (ELISA) developed in the lab of Dominique Alfandari, professor of developmental biology at UMass Amherst.

Arcaro has begun research on the breastmilk of 30 women from across the country, all of them healthcare professionals, who are providing breastmilk samples from before and after receiving the vaccine. “No one knows what the breastmilk response to the vaccine will be,” Arcaro says.

She also is still recruiting new moms nationwide who have a current infection, a positive COVID-19 test and are breastfeeding babies less than five months old. The women are sent a kit via Federal Express with everything they need to collect breastmilk samples on 12 days, which they freeze. The women provide a fresh sample on the final day, as well as a blood spot and an infant stool sample, and return the kit in a prepaid Federal Express box to Arcaro’s lab at UMass Amherst.

Breastfeeding women infected with the coronavirus who are interested in participating or learning more may email Arcaro at breastmilk@umass.edu.