Author Affiliation: School of Public Health, University of Michigan, Ann Arbor, Mich.
Inactivated influenza vaccine was originally developed during World
War II to protect healthy adult members of the United States armed services.
With its major interest in preventing influenza to maintain military readiness,
the US military conducted a large number of randomized controlled trials from
1943 through 1969, which demonstrated that the vaccine was 70% to 90% efficacious
in preventing laboratory-confirmed clinical influenza as long as the virus
in the vaccine resembled the virus that was circulating.1
The current influenza vaccine is similar to the vaccines used in those trials,
with higher potency and fewer adverse events. Its efficacy in healthy adults
was recently reconfirmed in a randomized trial in which efficacy against laboratory-confirmed
influenza was 88%.2
Monto AS. Preventing Influenza in Healthy AdultsThe Evolving Story. JAMA. 2000;284(13):1699-1701. doi:10.1001/jama.284.13.1699