Feb. 23, 2023 – The flu vaccine has been highly effective this year, the CDC says, despite flu season getting off to one of the earliest and strongest starts on record.
“Vaccination provided substantial protection against inpatient, emergency department and outpatient illness across all ages,” said Mark Tenforde, MD, of the CDC’s Influenza Division, according to CNN.
Health officials estimate that, so far this flu season, vaccines reduced the risk of hospitalization due to the respiratory virus by nearly 50% among adults, and by nearly 75% among children.
Each season, the vaccine is different and is formulated in advance to target strains of the virus predicted to be in wide circulation. The accuracy of the predictions can vary widely. In recent years, effectiveness has ranged from 29% to 40%, although historically the rate has dipped as low as 10% or done as well as 60%.
This season, positive flu cases peaked during the end of November and early December, when 26% of all tests came back positive. The mid-holiday season surge caused alarm that the flu could overwhelm hospitals, many of which were already grappling with high levels of another respiratory virus known as RSV. Instead, flu levels have steadily declined and, currently, just 1.7% of all tests are positive for flu.
Officials noted that the flu vaccine was particularly effective among children this year. However, the rate of pediatric flu deaths has rebounded to near pre-COVID levels. There have been 111 pediatric flu deaths so far this season. There was one pediatric flu death in the 2020-21 season and 45 in 2021-2022.
One new analysis showed that people 65 and older who got flu vaccines were 39% less likely to visit the emergency room or urgent care and 42% less likely to be hospitalized for flu or complications from it. People with weakened immune systems, such as cancer patients or organ transplant recipients, were 30% less likely to visit the ER or urgent care for flu.
So far this season, the flu has sickened at least 25 million people nationwide, and caused 280,000 hospitalizations and 18,000 deaths, according to the CDC’s most recent weekly update. The agency continues to recommend that anyone age 6 months and older should get a flu shot as long as flu activity continues. Flu season typically ends in April or May.