More jabs needed
The seasonal influenza virus is extremely adaptable: each year, it evolves ways to evade vaccines, forcing vaccine makers to come up with new formulations. That evolution, known as antigenic drift, occurs when viruses change the sequence of their major surface protein, known as hemagglutinin (HA). HA is one of the primary targets of the natural immune response and key to eliciting an effective vaccine response. A paper published in today's issue of Science suggests how the spread of influenza between vaccinated and non-vaccinated (naïve) individuals may affect antigenic drift. The results suggest that maximizing the number of vaccinated people could slow antigenic drift, according to the research team. “Our model predicts that decreasing the immunologically naïve population — by increasing the number of children vaccinated against influenza, for example — could slow the rate of antigenic drift and extend the duration of effectiveness of seasonal...