Mice treated with antibiotics to remove most of their intestinal bacteria or raised under sterile conditions have impaired antibody responses to seasonal influenza vaccination, researchers have found.
The findings suggest that antibiotic treatment before or during vaccination may impair responses to certain vaccines in humans. The results may also help to explain why immunity induced by some vaccines varies in different parts of the world.
In a study to be published in Immunity, Bali Pulendran, PhD, and colleagues at Emory University demonstrate a dependency on gut bacteria for strong immune responses to the seasonal flu and inactivated polio vaccines.
Antibody responses to vaccines containing immune stimulating substances called adjuvants were not affected by a lack of gut bacteria. For example, bacteria were not critical for responses to the Tdap (Tetanus-Diphtheria-Pertussis) vaccine.
