An unusually early flu season has bypassed the traditional Southern states to strike the West Coast, prompting health experts to push for immediate vaccinations.
The arrival of flu season has defied expectations this year. skipping its traditional starting point in the South to take hold early across Western states. By late September. communities that usually remain clear of the virus for weeks were already grappling with rising activity. a shift that has prompted health officials to drop a blunt warning: get vaccinated now. before the cycle intensifies.
In Los Angeles County, flu activity began its ascent on Sept. 28, weeks ahead of the typical early-November onset. For local health systems. this isn’t necessarily a harbinger of a catastrophic season. but it is a reminder of the virus’s inherent volatility. As Dr. Dawn Terashita. associate director of the Los Angeles County Department of Public Health’s Acute Communicable Disease Control Program. noted. the virus remains consistently unpredictable due to its constant mutation.
The geographical reversal has been just as striking. While the flu traditionally migrates from the Southeast and South toward the West Coast. this year saw the Western region face the brunt first. Testing data confirms the trend: positivity rates are currently high in the San Francisco Bay Area and moderate across Southern California and the Sacramento Valley. While hospital admission rates for influenza across California remain low. the mortality toll is already climbing. with 34 flu-related deaths reported statewide.
San Francisco recorded its first flu death of the season last week. While Los Angeles County has yet to log a fatality. the memory of the 2025-26 season—which saw 126 deaths—remains a baseline for the county’s preparations. The current landscape is a stark departure from the COVID-19 years. when social distancing and masking kept flu cases at near-zero levels. As those measures faded. upticks in 2024 and 2025 signaled a return to pre-pandemic normalcy. and this year’s early start confirms the virus is back in full force.
For experts, the urgency to vaccinate is sharpened by the current profile of the virus. Dr. Peter Chin-Hong. an infectious-disease expert at UC San Francisco. emphasized that the circulating variant. H3N2 subclade K. is well-matched to this year’s vaccine. This alignment reduces the risk of a major mismatch, a persistent fear in earlier years. Chin-Hong advises that most people aim for their shots before mid-October. noting that options now range from standard injections and needle-free nasal sprays to high-dosage vaccines specifically designed for those 65 and older.
The unpredictable nature of the virus creates a race against time. While California health officials monitor whether this early start will translate into a more severe season—reminiscent of the 2009 H1N1 pandemic—the focus remains on public intervention. The efficacy of the upcoming months remains in the hands of the public; as vaccination behavior dictates the trajectory of the season. officials are operating in a state of watchful waiting. urging residents not to delay the one defense known to hold the line.
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