Anti-RBD IgA and IgG Response and Transmission in Breast Milk of Anti-SARS-CoV-2 Vaccinated Mothers.

Anti-SARS-CoV-2 IgA and IgG can be found in the milk secretion of mothers vaccinated with mRNA vaccines and, presumably, these antibodies should offer protection to the newborn, considering that the antibodies' titers did not decrease after 60 days. The antibody response is directly proportional to the breastfed child's age, but the amount of anti-RBD IgA decreases with the baby's rank. The antibody response did not depend on the vaccine type, or on the mother's age.