Connecticut Seasonal Influenza Statistics


Influenza (flu) is a respiratory illness caused by influenza viruses. This contagious disease can cause mild to severe symptoms that may require hospitalization. Certain health conditions (asthma, diabetes, heart disease, etc.) can result in a higher risk of getting sick with influenza. Age may also play a role in who gets sick and has more severe symptoms. To learn about how to prevent getting sick with influenza, visit the Department of Public Health (DPH) Immunizations Program.  


In Connecticut, the DPH uses multiple surveillance systems to monitor circulating influenza viruses. Seasonal flu viruses can be detected throughout the year; however, seasonal flu activity generally begins as early as October and November and can continue through late May. The weekly surveillance reports show how this year's flu season is developing. Each report is progressive and includes data starting from the beginning of this flu season.



This Week's Complete Flu Update



NOTE: The ongoing COVID-19 pandemic has resulted in a reduction in influenza testing, and delays in reporting.






 This year's flu season data collection begins with Week 35; August 25, 2019.

A snapshot of this week's flu activity in Connecticut. Brief information about this week's flu activity in Connecticut. 

Weekly Influenza Reports

Annual Influenza Seasonal Summaries

National influenza statistics through Flu View.

International influenza activity is available through the World Health Organization.

Get a flu vaccine to help prevent severe illness.


Influenza Geographic Activity classification

The estimated level of geographic spread of influenza activity is determined weekly. Although this level does not measure the severity of influenza illness, it does show the impact of influenza on the public and healthcare centers.


Geographic spread of influenza activity is reported as: 

Geographic Activity Classification




This page last updated 4/16/2020.