Influenza rates are the highest in over a decade
February 15, 2025
Percentage of outpatient visits for influenza-like illness
Source: Centers for Disease Control and Prevention, February 10, 2025. Dotted line (3%) is epidemic level.
Over 7% of all office visits are for influenza-like illness, and wastewater and test results show that most of this illness is Influenza A. RSV infections are decreasing, and COVID has caused less disease than in past years. The CDC has not detected bird flu in laboratory screening or emergency department monitoring, although avian influenza has been found in wastewater sampling in various parts of the country.
Office visits for influenza-like illness are highest in children under 5 years of age (17%), and so far this season 57 children have died of influenza. Antiviral medicines given shortly after the beginning of symptoms can lead to quicker recovery, and those who are not vaccinated can still be vaccinated. Flu shots typically begin to provide some level of protection within about a week as the immune system starts responding. However, full protection is usually achieved within two weeks after vaccination, as it takes time for the body to develop its immune response.
This season’s high rate of influenza infection could be due to lower vaccination rates, especially among young children, and continued decrease of population immunity due to the very mild flu seasons during the COVID-19 pandemic.
In addition to the CDC, my “go to” sources for this information are two epidemiologists who post regularly on Substack:
Your Local Epidemiologist (Katelyn Jetelina)
Force of Infection (Caitlin Rivers)