Breast milk of mothers who have been fully vaccinated against COVID-19 contains antibodies that can protect babies from the virus, a new study finds.
The research which was conducted by scientists at the University of Florida (UF) and was published in the journal Breastfeeding Medicine suggested that vaccinated mothers breast-feeding are likely to pass on 100 times more antibodies to their children than unvaccinated mothers.
“Our findings show that vaccination results in a significant increase in antibodies against SARS-CoV-2 — the virus that causes COVID-19 — in breast milk, suggesting that vaccinated mothers can pass on this immunity to their babies, something we are working to confirm in our ongoing research,” Joseph Larkin III, Ph.D, senior author of the study and an associate professor in the UF/IFAS department of microbiology and cell science, said in a statement released by the university.
“Think of breast milk as a toolbox full of all the different tools that help prepare the infant for life. Vaccination adds another tool to the toolbox, one that has the potential to be especially good at preventing COVID-19 illness,” said the study’s co-author Dr. Josef Neu in a statement, who is also a researcher at the university’s College of Medicine’s department of pediatrics, division of neonatology.
The study was conducted between December 2020 and March 2021, which was around the time when Pfizer and Moderna’s COVID-19 vaccines first became available to healthcare workers.
Twenty one lactating healthcare workers, who were never contracted with COVID-19 before, were recruited to take part in the study. Their breast milk and blood were sampled three times: before getting the vaccine, after the first vaccine dose and then after the second shot.
As a result, doctoral student and co-author of the study Lauren Stafford, said that they had seen a “robust antibody response in blood and breast milk after the second dose- about a hundred-hold increase compared with levels before vaccination.”
“Typically, expectant mothers are vaccinated against whooping cough and flu because these can be serious illnesses for infants. Babies can also catch COVID-19, so routine vaccination of mothers against the virus could be something we seen in the future,” another co-author of the report and resident in the university’s pediatrics department, division of neonatology Dr. Vivian Valcarce, noted.
Newborns tend to have weaker immune systems, making them extra vulnerable to infections and illness because they are too young to respond to some vaccines types properly, the researchers told online news media StudyFinds.org. During this vulnerable period, babies rely on their mother’s breast milk to provide them with immunity because it contains different types of antibodies that help protect them against an array of diseases.
In a blog post on the university’s website, the team stated that they will continue to explore how breast milk containing COVID-19 antibodies acquired indirectly from vaccination protects babies.
“We would like to know if infants who consume breast milk containing these antibodies develop their own protection against COVID-19,” Larkin said.
“In addition, we would also like to know more about the antibodies themselves, such as how long they are present in breast milk and how effective they are at neutralizing the virus,” he added.
While there are still some unanswered questions, the team said that their initial findings have made them optimistic, encouraging them to continue their research.
“We are also excited to see many other simultaneous studies conducted around the world that also show antibodies in the breastmilk of vaccinated mothers,” Neu said.
“That means our study validates a growing body of evidence.”