Breast‑milk IgA from McMaster neutralizes RSV, influenza A (including H5N1) and other respiratory viruses
McMaster University, with biotech partner Lactiga, reports (14 Oct 2026, Science Advances) that IgA antibodies purified from breast milk neutralize RSV, adenovirus and influenza A including H5N1. Samples from 120 donors were pooled to broaden antibody diversity; mucosal (nasal) delivery protected animal models, including immunodeficient ones.
Researchers at McMaster isolated immunoglobulin A from pooled breast‑milk donations (120 donors) and demonstrated broad antiviral activity in cell assays and full protection in animal infection models. Pooling increased the range of antibodies recovered, and mucosal administration via the nose achieved effective protection, even in immunodeficient animals. The study, published 14 October 2026 in Science Advances and performed in collaboration with Lactiga, presents a translational avenue for passive immunization while not claiming immediate clinical availability.