Experts Warn Flu Season May Intensify Due to New Strain

Medical experts are predicting a significant escalation in flu activity in the coming weeks, driven by a new strain known as subclade K. While this flu season has started relatively mild, the emergence of this strain, which arose after vaccine production, poses a heightened risk for illness. The current flu vaccine remains the best defense against infection, despite its limitations against this new variant.

Data from the United Kingdom reveals that hospitalizations due to the flu are currently at their highest for this time of year, according to the U.K. National Health Service. Lisa Sollot, the respiratory disease program coordinator for the Virginia Department of Health, noted that subclade K first appeared in Australia towards the end of its flu season and has since been detected in Japan and the United States.

Recent statistics indicate that the vaccine is approximately 32-39% effective in preventing flu infection overall, but it shows improved effectiveness of 72-75% in children, as reported by the University of Virginia. Frederick G. Hayden, a professor at the university and a member of its Division of Infectious Diseases and International Health, co-authored an article in the Journal of the American Medical Association discussing these findings. He highlighted that subclade K is a subtype of the strain responsible for last season’s severe flu, which was marked by a tragic increase in pediatric deaths. Consequently, this season is expected to be similarly severe.

According to a report released on December 11, 2023, by the Centers for Disease Control and Prevention (CDC), the 2024-25 influenza season, primarily driven by influenza A H1N1 and H3N2 viruses, has already resulted in high severity across all age groups, with particularly alarming pediatric mortality rates. “Unfortunately, we are seeing the circulation of a new variant of the H3N2 virus for which our vaccines may be somewhat less effective,” Hayden stated in a release from the university. He emphasized that although the vaccines might not be perfectly effective, they significantly reduce the risk of severe illness and limit the spread of the virus.

Sollot further explained that historically, high-severity flu seasons do not occur in consecutive years. “Low vaccination rates combined with subclade K’s emergence may potentially lead to a severe season,” she cautioned, although she acknowledged the uncertainty of its severity.

Currently, vaccination rates in Virginia are concerningly low, with only about 28% of residents across all age groups vaccinated. The figures are even lower for children aged 5-17, where the rate stands at 20.6%. In contrast, individuals aged 50 and older have a vaccination rate of 39.8%. CDC data from the previous flu season revealed that about 90% of children who died from the flu were unvaccinated, with half of those children lacking any underlying health conditions.

“Those are really shocking statistics for the season,” Sollot said. She urges everyone to get vaccinated, maintain proper hygiene, and stay home when feeling unwell. The CDC recommends flu vaccination for everyone aged six months and older, with only rare exceptions.

With the flu season expected to intensify, public health officials are emphasizing the importance of vaccination and preventive measures to mitigate the impact of this potentially severe outbreak.