Flu Season Intensifies
Flu season is ramping up, and the latest data from the Centers for Disease Control and Prevention reveals some concerning trends. This winter is shaping up to be quite challenging.
Recent surveillance by the CDC indicates a marked increase in seasonal flu activity across much of the United States. Some regions have already experienced school closures due to flu surges, and troublingly, there has been at least one pediatric death linked to the illness. This season seems to be dominated by a new variant of H3N2 flu, called subclade K, which isn’t well-matched to our existing vaccines.
A New Challenge Emerges
Typically, multiple strains of influenza A and B circulate during flu season. Since vaccine production takes time, public health officials attempt to predict which strains will be prevalent, sometimes up to nine months in advance.
However, subclade K has complicated matters significantly. This variant appeared toward the end of last winter in the Southern Hemisphere, proving to be genetically distinct and fitting enough to replace other strains of H3N2 quickly. Compounding the issue, the seasonal flu vaccine has not been effective against subclade K, which lowers its ability to prevent infections or serious illness.
This variant has already lengthened the flu season in parts of the Southern Hemisphere, like Australia and New Zealand. It has also triggered an earlier-than-usual flu season in several European countries. For instance, in the UK, subclade K is contributing to a surge in hospitalizations and what officials are calling an “unprecedented wave of super flu.”
The most current CDC data, which covers the first week of December, indicates that overall respiratory virus activity in the U.S. is currently low, though this likely won’t last. Cases requiring medical attention are increasing, with 8.1% of lab tests returning positive for flu—up from 5% just two weeks ago. Hospitalizations related to the flu are also on the rise, and last week marked the first reported pediatric death associated with this virus. Schools in states like Missouri and Iowa have already had to close due to flu outbreaks.
Steps to Take Against the Flu
Most new infections in the U.S. are attributed to H3N2, suggesting that subclade K is also making its presence felt here. Given the situation in other areas, it’s hard to feel optimistic.
That said, getting vaccinated continues to be an essential proactive measure this flu season. Even though it doesn’t perfectly match the subclade K strain, early data from the UK suggests that the seasonal vaccine still provides some protection against severe illness, especially for children.
Additionally, it’s crucial to maintain good hygiene—wash your hands frequently, stay home if feeling unwell, and consider wearing a mask in high-risk settings. Investing in well-fitting, high-quality masks like KN95 or N95 can significantly boost your protection.
