With the American Academy of Pediatrics (AAP) now recommending infants as young as six months old receive a flu shot, a new study is exploring how early exposure to the flu can affect consumers’ immune systems as they age.
According to the findings, consumers may be less likely to experience severe symptoms later in life if they’re exposed to the virus early on. The researchers say their findings could speed up the development of future treatment options.
"We hope the findings from our study will improve our understanding of influenza epidemiology and the low and variable effectiveness of the seasonal flu vaccine," said senior author Sarah Cobey. "This would lead to better forecasting and vaccination strategies to help combat future flu seasons."
Identifying infection risk
To understand how early exposure to the flu could affect the likelihood of becoming infected in the future, the researchers analyzed flu data from consumers in Marshfield, Wisconsin. The dataset included stats from a decade’s worth of flu seasons, and all participants were at least six months old.
The researchers explained that there are three primary strains of the flu: A, which can be broken down into A(H1N1) and A(H3N2), B, and C. They assessed the risk of future infection based on early life exposure to all three variations of the virus.
Ultimately, the researchers learned that being exposed to the flu during infancy is likely to protect consumers as they age. Exposure to a specific strain of the flu in early life reduced the likelihood of severe symptoms when exposed to that same strain again. The research team said this correlation was stronger for the influenza A(H1N1) strain than it was for the A(H3N2) strain, the latter of which was responsible for the swine flu outbreak in 2009.
When it comes to the flu vaccine, the researchers learned that consumers respond differently to it at different ages. Because the flu shot is modified each year to adapt to the newest strains, this is important information for both consumers and medical experts.