The flu season is well underway, and it’s turning out to be quite dangerous, especially for young children. Reports from several states indicate the first flu-related deaths among kids this week. Additionally, cases and hospitalizations are on the rise across the U.S., with some areas seeing unprecedented spikes. This season is largely attributed to a new strain of H3N2, specifically subclade K.
Tragic deaths
Due to the holiday period, the latest flu statistics from the Centers for Disease Control and Prevention (CDC) are nearly two weeks old. Even so, it’s clear that this season is shaping up to be particularly severe.
As of December 20, flu activity was reported as high or very high in 32 regions across the country, with another eight jurisdictions seeing moderate levels. The cumulative hospitalization rate in week 51 is now the third highest recorded in the last 15 years, surpassed only by the 2022-23 and 2023-24 seasons.
Some states are experiencing even worse conditions. For instance, New York health officials announced last week that they logged the highest number of flu cases ever recorded in a single week, with 71,123 positive tests during the week of December 20.
So far, at least eight pediatric deaths due to flu have been documented this winter, according to the CDC, although local health officials and community members have reported more. On December 30, the Kentucky Department for Public Health reported a child from Kenton County had died of flu, and notably, hadn’t received a flu shot. The following day, Ohio reported its first flu-related pediatric death, involving a teenager from Greene County. Moreover, on Thursday, a social media influencer from Minnesota shared that his five-year-old son passed away after battling a severe case of the flu.
“This is a tragic loss and our thoughts are with the family,” stated Bruce Vanderhoff, director of the Ohio Department of Health, in a public statement. “It’s a poignant reminder that, while influenza is widespread, it’s a serious health risk, and we encourage parents to protect their children.”
A record bad winter?
In typical winters, the flu infects millions, leads to hospitalizations for hundreds of thousands, and results in tens of thousands of deaths. However, there’s a chance we could experience two consecutive tough seasons. Last winter, for example, at least 280 children died from the flu in the U.S., marking the highest mortality rate for pediatric flu in a non-pandemic context in modern history.
This current season is largely driven by the emergence of subclade K, a variant of H3N2 that differs genetically from the strains that experts had predicted would be circulating. Since surfacing in the Southern Hemisphere’s winter, K has rapidly become the predominant flu strain worldwide, including in the U.S. While it doesn’t seem to cause more severe illness than other H3N2 variants, it has triggered intense, early, or prolonged waves of illness across various regions, such as the UK, Japan, and Australia.
Even though the seasonal flu vaccine does not match subclade K perfectly, getting vaccinated is still advisable if you haven’t done so. Data from the UK suggests that this season’s vaccine remains effective in preventing serious flu complications, particularly among children.
