The Centers for Disease Control and Prevention (CDC) said this year’s flu shot provided “substantial protection” against the virus, majorly reducing the risk of hospitalization in those vaccinated.
The CDC said in a release on Wednesday that the vaccine reduced the risk of hospitalization resulting from influenza A, one of the two types that cause the most illness among humans, among children by nearly three-quarters and among adults by almost half.
The release states that the vaccine also gave significant protection against illness and emergency room visits resulting from the flu, with vaccinated individuals half as likely to experience those as unvaccinated people.
The CDC presented its findings during a meeting of its Advisory Committee on Immunization Practices, which develops recommendations for people using vaccines, in Atlanta.
Data shows vaccine effectiveness against the H3N2 viruses reached 45 percent, which is higher than has ever been seen for this kind of virus. It has previously only been about 30 percent.
Effectiveness for the H1N1 viruses, known as circulating influenza A, was at 56 percent.
“These data underscore that flu vaccination can offer substantial benefit against flu and its potentially serious complications,” the release states.
The release states the higher effectiveness this season was likely a result of vaccination initiating strong immunity against a range of viruses that are circulating during the season.
The figures are a major improvement from the 2021-2022 season, when the CDC estimated that the vaccine was 25 percent effective against emergency room or urgent care visits and hospitalization.
Adults who have a documented immunocompromising condition were also 44 percent less likely to be hospitalized from flu-related complications when they received the vaccine.
Health experts warned in the fall of the onset of a “tripledemic,” signaling an early and particularly difficult flu season, continued COVID-19 infections and respiratory syncytial virus. Younger children are especially at risk of developing severe cases of the latter virus.
New COVID-19-related hospital admissions did rise to two per 100,000 people in early January, but they have fallen to near 1 per 100,000 recently.
Almost 40 percent of U.S. households said in a survey earlier this month that someone living in their home became sick with at least one of the three viruses during cold and flu season.