Reason for optimism

Abstract

The US Centers for Disease Control and Prevention (CDC) claims that the single best way to prevent seasonal flu is to get vaccinated each year.1 Such confidence in influenza vaccines seems misplaced for two reasons. Firstly, if CDC viral surveillance data are correct, then in recent years true influenza viruses have caused an average of only 12% of influenza-like illness2 (the syndrome the public thinks of as "flu" and, most critically, the syndrome the public is trying to avoid). Since influenza vaccine does not work against non-influenza viruses,3 how can the agency responsibly claim vaccines are the best way to prevent seasonal flu?