A new study conducted jointly by Tel Aviv University and the Tel Aviv Sourasky Medical Center–Ichilov found that vaccinating breastfeeding mothers promotes the production of important antibodies in their breast milk, potentially contributing to the protection of their nursing babies.

The leading team at TAU included Dr. Yariv Wine and PhD student Aya Kigel from the Shmunis School of Biomedicine and Cancer Research at the George S. Wise 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 Professor Ariel Many.

The purpose of the study was to discover whether Pfizer’s COVID-19 vaccine was effective in producing antibodies in breast milk, and 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 ten breastfeeding mothers. The volunteers received two shots of the vaccine, 21 days apart, and the levels of antibodies in both their blood and breast milk were tested at four points in time following vaccination.

The study indicated that the blood and breast milk 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 breast milk, the significant increase occurs 14 days after the first shot and continues seven days after the second shot. The researchers also found that the antibodies developing in breast milk hold the potential to neutralize the virus,  blocking it from binding with receptors on host cells.

“The encouraging data show that vaccinating breastfeeding mothers promotes the production of important antibodies in their breast milk, potentially protecting their nursing babies from the disease,” Dr. Wine says.

Tel Aviv University (TAU) is a globally top-ranked university, a leading research institution, and a center of discovery. As Israel’s largest public institution of higher learning, TAU is home to 30,000 students, including 2,100 international students from over 100 countries. The University encompasses nine faculties, 35 schools, 400 labs, and has 17 affiliated hospitals in its network.

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