Vaccinating breastfeeding mothers against COVID-19 may help protect their nursing babies

A new study conducted jointly by the Shmunis School of Biomedicine and Cancer Research and the Tel Aviv Sourasky Medical Center – Ichilov found that vaccinating breastfeeding mothers promotes the production of important antibodies in their breastmilk, potentially contributing to the protection of their nursing babies. 

The leading research team at Tel Aviv University included Dr. Yariv Wine and the PhD student Aya Kigel from the Shmunis School of Biomedicine and Cancer Research at the Faculty of Life Sciences. The team at the Lis Maternity and Women's Hospital at the Tel Aviv Sourasky Medical Center was led by Dr. Michal Rosenberg-Friedman and Prof. Ariel Many.

According to the researchers, the purpose of the study was to discover whether Pfizer's COVID-19 vaccine was effective in producing antibodies in breastmilk, and also to determine the qualities of these antibodies (in other words, whether they have the potential to neutralize the virus).

The study was conducted during January and February 2021, soon after the vaccines arrived in Israel, and included 10 breastfeeding mothers. The volunteers received two shots of the vaccine, 21 days apart, and the levels of antibodies in both their blood and breastmilk were tested at four points in time, following vaccination.

The study indicates that the blood and breastmilk are well synchronized with one another, with regard to the rise of the levels of the specific antibodies generated by the vaccine. In both blood and breastmilk, the significant increase occurs 14 days after the first shot, and continues 7 days after the second shot.

The researchers also found that the antibodies developing in breastmilk hold the potential to neutralize the virus. (They can block the virus from binding with receptors on host cells and are important for preventing the disease).

Dr. Wine: "The encouraging data show that vaccinating breastfeeding mothers promotes the production of important antibodies in their breastmilk, potentially protecting their nursing babies from the disease."

The paper is currently undergoing peer review.
 

To read the paper: https://www.medrxiv.org/content/10.1101/2021.03.06.21252603v1