Back to Cold & Flu
Weekly Flu Update: Flu Exceeds Annual Baseline
December 13, 2025 at 05:57 PM EST
UPDATED by WeatherBug Meteorologist, Andrew Rosenthal

Colder temperatures mean that winter is in full swing across the U.S., and with the changing seasons come the influenze virus.
Patient visits for respiratory illnesses increased to 3.2%, below the national baseline of 3%. One pediatric death this week could be attributed to the flu. Of all clinical lab tests, about 8.1% were positive for influenza.
Our flu surveillance product will continue to focus on the severity of the flu rather than the geographic spread. This information is reported to the U.S. Centers for Disease Control and Prevention (CDC) by each state’s health department, ranging on a scale from “minimal” to “very high” levels of activity.
States and territories reporting flu include the following activity and trends:
New York City reported Very High flu, an increase from last week in which that area had High flu activity.
High (4 states): Colorado, Louisiana, New Jersey and New York.
Flu Facts:
The CDC recommends that everyone older than six months get the seasonal flu vaccine, either via an injection or nasal spray. Consult with your doctor or pharmacist to learn about flu vaccine side effects, precautions, and vaccine options—several multi-strain variations are available this year.
Due to certain health restrictions, not everyone is eligible to receive the flu shot. If you cannot get vaccinated, there are other ways to minimize your risk of contracting and spreading the flu:
---
Source: U.S. Centers for Disease Control and Prevention
Patient visits for respiratory illnesses increased to 3.2%, below the national baseline of 3%. One pediatric death this week could be attributed to the flu. Of all clinical lab tests, about 8.1% were positive for influenza.
Our flu surveillance product will continue to focus on the severity of the flu rather than the geographic spread. This information is reported to the U.S. Centers for Disease Control and Prevention (CDC) by each state’s health department, ranging on a scale from “minimal” to “very high” levels of activity.
States and territories reporting flu include the following activity and trends:
New York City reported Very High flu, an increase from last week in which that area had High flu activity.
High (4 states): Colorado, Louisiana, New Jersey and New York.
- New Jersey reported moderate flu activity last week, marking a one-step increase.
- Colorado, New York and Louisiana reported high flu activity last week and remain at that level.
- Connecticut, Georgia, Massachusetts, Michigan, Rhode Island, South Carolina and Texas all reported low flu activity last week, and have increased by one level.
- Idaho reported moderate flu activity last week and remains at that level.
- Puerto Rico reported High flu activity last week and thus has dropped one level.
- Alabama, Indiana, Minnesota, Pennsylvania and Virginia all report flu activity increasing from minimal to low.
- California, Washington, D.C., Florida, Maryland, Missouri, New Mexico, North Carolina, Ohio and Oregon all reported low flu activity last week and once again report low flu activity this week.
- Hawaii decreased from low flu activity to minimal flu activity.
- All of the remaining states had minimal flu last week.
Flu Facts:
The CDC recommends that everyone older than six months get the seasonal flu vaccine, either via an injection or nasal spray. Consult with your doctor or pharmacist to learn about flu vaccine side effects, precautions, and vaccine options—several multi-strain variations are available this year.
Due to certain health restrictions, not everyone is eligible to receive the flu shot. If you cannot get vaccinated, there are other ways to minimize your risk of contracting and spreading the flu:
- Avoid close contact with those who are sick.
- If you are sick, avoid exposing others by staying home from work or school.
- Cover your mouth and nose when sneezing or coughing.
- Wash your hands frequently.
- Avoid touching your eyes, nose, or mouth.
---
Source: U.S. Centers for Disease Control and Prevention