### Rising Flu Cases in the U.S.: A Surge Driven by New Strain The Centers for Disease Control and Prevention (CDC) has reported a significant increase in flu activity across the United States, with five states experiencing "very high" levels of influenza cases. This surge is largely attributed to a new strain of the virus, known as subclade K of H3N2, which has led to a notable rise in positive tests and healthcare visits. Health officials are urging the public to get vaccinated and maintain good hygiene practices to mitigate the spread of the virus [https://710wor.iheart.com/content/2025-12-23-five-states-report-very-high-flu-activity-cdc-says]. ### Breakdown of Current Flu Situation 1. **Flu Case Statistics**: - Nearly **5 million flu cases** have been reported in the U.S. as of late December 2025, with New York City showing the highest activity levels [https://www.healthandme.com/health-news/flu-cases-in-us-reach-5-million-mark-reveals-cdc-data-article-153328584]. - The CDC has recorded **4.6 million illnesses**, **49,000 hospitalizations**, and **1,900 deaths** linked to the flu this season [https://www.healthandme.com/health-news/flu-cases-in-us-reach-5-million-mark-reveals-cdc-data-article-153328584]. 2. **Geographical Spread**: - States such as **Colorado, Louisiana, and New York** are experiencing the fastest increases in flu cases, indicating a widespread outbreak [https://www.themirror.com/news/us-news/chilling-map-shows-super-flu-1573393]. 3. **Vaccine Efficacy**: - Despite a mismatch between the circulating strains and the vaccine, health experts emphasize that vaccination still provides significant protection against severe illness [https://www.healthandme.com/health-news/flu-cases-in-us-reach-5-million-mark-reveals-cdc-data-article-153328584]. ### Supporting Data on Flu Activity - **Flu Cases**: - Total reported cases: **5 million** - Hospitalizations: **49,000** - Deaths: **1,900** - **States with High Activity**: - **New York City**: Highest levels of flu activity - **Colorado**: Rapid increase in cases - **Louisiana**: Notable rise in flu infections ### Summary of Findings 1. **Current Flu Situation**: The U.S. is facing a significant flu outbreak, with nearly **5 million cases** reported, primarily driven by the H3N2 subclade K strain. 2. **Geographical Impact**: States like New York, Colorado, and Louisiana are particularly affected, with New York City leading in reported cases. 3. **Health Recommendations**: Vaccination is strongly recommended despite the current vaccine mismatch, as it still offers protection against severe outcomes. In conclusion, the ongoing flu season is marked by a substantial increase in cases, particularly in certain states, necessitating public health measures to encourage vaccination and hygiene practices to control the spread of the virus [https://710wor.iheart.com/content/2025-12-23-five-states-report-very-high-flu-activity-cdc-says, https://www.healthandme.com/health-news/flu-cases-in-us-reach-5-million-mark-reveals-cdc-data-article-153328584].