The flu virus infects up to one-fifth of the U.S. population each year and kills thousands of people, many of them elderly. A new study explains why the flu vaccine is less effective at protecting older individuals, the people it is supposed to protect.
Flu vaccines, which contain proteins found in circulating viral strains, offer protection by eliciting the production of antibodies -- proteins that help the immune system identify pathogens and protect against infectious disease. While vaccination is considered the most effective method for preventing influenza, it is less effective in the elderly. But until now, the molecular mechanisms underlying this decrease in vaccine efficacy were unknown.