A new study shows that individuals who received the flu vaccine were protected for up to 6 months after the vaccination.
“Few studies have assessed how quickly protection against influenza declines within a year following vaccination, specifically among US populations,” said Dr. Jennifer Radin, at the Naval Health Research Center in San Diego, CA.
For this study at the Naval Health Research Center, the researchers assessed influenza vaccine protection using febrile respiratory illness surveillance, which identified Department of Defense (DoD) non-active duty beneficiaries of all ages who presented with fever, cough or sore throat at three outpatient facilities in San Diego, CA and Great Lakes, Illinois. An upper respiratory swab was taken from a sample of these individuals and then was tested in the laboratory for influenza. Researchers measured influenza vaccine protection declines using data from 1,720 individuals throughout the course of four flu seasons, from the 2010-2011 season through the 2013-2014 season.
“Previous studies have found that protection from contracting influenza declines over time following influenza vaccination due to decreasing antibody levels,” said Radin, “However, we found during this study that those who received the vaccine had moderate, sustained protection up to 6 months post-vaccination, the duration of most influenza seasons. This means flu vaccination reduced one’s risk of a doctor’s visit by approximately 50-70%.”