Flu activity has surged in California, with the latest report from the U.S. Centers for Disease Control and Prevention (CDC) indicating that levels were categorized as “high” for the week ending on December 20, 2023. This marks a significant increase from the previous week’s classification of “moderate.” The rise in flu cases coincides with the ongoing holiday travel season, prompting public health officials to closely monitor the situation.
Nationwide, flu-like activity is reported as high or very high in more than half of the country. The CDC estimates that there have been approximately 7.5 million illnesses, 81,000 hospitalizations, and 3,100 deaths attributed to the flu this season. Notably, there have been at least eight reported child deaths linked to flu infections, including one case in Sacramento County. It remains unclear if this specific case has been factored into the national statistics.
The California Department of Public Health notes that flu activity is on the rise across all regions of the state, with a marked increase in test positivity rates among children. Although hospitalizations remain relatively low, officials anticipate an upward trend in the coming weeks. A variant known as “subclade K,” which is associated with the H3N2 strain, is believed to be contributing to this recent uptick in cases. This particular strain has been known to lead to more severe illness in older adults, raising concerns among health experts.
The characteristics of subclade K—whether it spreads more easily or poses a greater risk—are still under investigation. The flu poses significant dangers to certain populations, particularly individuals aged 65 and older, pregnant women, young children, and those with chronic health conditions such as asthma, diabetes, and heart disease.
Vaccination remains a critical defense against the flu. The CDC and various medical organizations recommend that everyone aged six months and older receive the flu vaccine. Although this season’s vaccine is not an exact match for subclade K, health professionals believe it can still provide at least partial protection. Currently, around 42% of adults and children in the United States have received their flu shot.
Individuals experiencing flu symptoms should be vigilant and consider taking steps to reduce their risk of contracting the virus. Staying informed about flu activity and vaccination options is essential, particularly during the holiday season when travel and gatherings increase the likelihood of virus transmission.
For more detailed information on flu activity across different states, please refer to the accompanying chart. As the flu season progresses, staying updated on public health recommendations will be crucial for individual and community health.
