Vaccinated moms’ breast milk may protect babies from COVID-19

By Elissa Wolfson, The Science Advisory Board assistant editor

January 13, 2023 -- University of Florida researchers have provided additional evidence that the breast milk of mothers vaccinated against COVID-19 helps protect infants too young to receive the vaccine. The findings, published January 12 in the Journal of Perinatology, found SARS-CoV-2 antibodies in the stool of infants who consumed this breast milk.

Previous studies showed that the breast milk of vaccinated mothers contained antibodies against SARS-CoV-2, the virus that causes COVID-19, but did not establish whether those antibodies were getting through their babies' gastrointestinal tract and providing protection.

Using a neutralization assay technique, the researchers isolated antibodies from the infants' stool and added them to a special line of cells containing receptors that the SARS-CoV-2 virus uses to enter cells. They then introduced a SARS-CoV-2 pseudovirus, which acts like the real virus but is safer for laboratory use. The pseudovirus is fluorescent; when it binds to a cell, the cell lights up.

When antibodies were present, fewer fluorescent cells were seen compared with controls containing no antibodies. While the SARS-CoV-2 virus is often thought to mainly affect the lungs, it can also invade the gut -- thus, finding antibodies in digestive products is significant. Researchers hypothesize that antibodies ingested in breast milk may provide a protective coating in the infants' mouths and gastrointestinal tract, generally "running interference" and preventing the virus from getting to the cells.

They concluded that the presence of SARS-CoV-2-specific antibodies in infant stool following maternal vaccination offers further evidence of the lasting transfer of these antibodies through breastfeeding, and may offer some measure of protection against the virus. Since children under six months of age cannot currently receive the vaccine, breast milk may be their only avenue for receiving immunity.

The study also measured and tested antibodies found in the mothers' blood plasma and breast milk soon after vaccination, and then again about six months later. The researchers found that the antibodies in the plasma and milk of newly-vaccinated people were better able to neutralize the virus; antibody levels decreased at the six-month mark, but remained higher than pre-vaccination levels.

As only 37 mothers and 25 infants participated in the study, larger studies are called for. However, the study adds to a growing body of research on how COVID-19 vaccination during pregnancy and breastfeeding may be protective for both parent and child.

"In our research, we're following the journey of the antibodies, from the time they are produced in mom after vaccination and now through the baby's digestive system. The next question is whether those babies are less likely to get COVID-19," noted University of Florida College of Medicine neonatology professor and coauthor Dr. Josef Neu in a statement.

Unusual antibody proves potent against Zika virus
Researchers have identified an unusual type of antibody that, even at miniscule levels, neutralizes the Zika virus rendering viral infection undetectable...
What pregnant women need to know about COVID vaccines
Addressing questions about COVID-19 vaccines for pregnant and postpartum women, a leading maternal-fetal medicine specialist explained that it's likely...
2003 SARS-CoV antibodies may provide some protection from SARS-CoV-2
A new study shows that antibodies against the original 2003 SARS-CoV also react with the current SARS-CoV-2 strain, but only with limited effectiveness....
Abpro's neutralizing COVID-19 mAb shows efficacy in monkeys
Abpro has published preclinical data in a Nature Communications article demonstrating the prophylactic and therapeutic production of neutralizing...
Synthetic nanobodies show potential for new COVID-19 therapies
Synthetic nanobodies may provide a practical avenue for the development of novel COVID-19 therapies compared to human antibodies, which are bulkier and...
Can SARS-CoV antibodies be used to develop universal coronavirus vaccines?
Can antibodies developed against SARS-CoV during the 2003 outbreak be used to prevent infection by SARS-CoV-2? In an October 9 study published in Science...
Immunoprecise highlights combo neutralization of antibodies
Immunoprecise Antibodies has conducted additional characterization of a subset of fully human, therapeutic SARS-CoV-2 antibodies that are potent and exhibit...
Oragenics identifies SARS-CoV-2 neutralizing antibodies
A stabilized prefusion spike protein licensed by Oragenics has generated neutralizing antibodies in mice during immunization against SARS-CoV-2, according...

Copyright © 2023

Science Advisory Board on LinkedIn
Science Advisory Board on Facebook
Science Advisory Board on Twitter