Influenza Surveillance and Statistics
In Connecticut, the Department of Public Health uses multiple systems to monitor circulating influenza viruses. During the influenza season, weekly flu updates are posted from October of the current year, through May of the following year. Annual summaries are also posted for comparison. The national flu picture may vary from what we are seeing on a state level.
This Week's Flu Update
Current Influenza Season Weekly Updates
To see how this year's influenza season has progressed, please click on the MMWR Week number that corresponds with the week's beginning and end date you are interested in seeing. Each report is progressive and includes data starting from the beginning of this flu season.
January 31, 2016
February 6, 2016
January 24, 2016
January 30, 2016
|2016||3||January 17, 2016||January 23, 2016||Regional|
|2016||2||January 10, 2016||January 16, 2016||Regional|
|2015||1||January 3, 2016||January 9, 2016||Regional|
|2015||52||December 27, 2015 ||January 2, 2016 || Regional|
|2015||51||December 20, 2015||December 26, 2015||Local|
|2015||50|| December 13, 2015||December 19, 2015||Local|
|2015||49||December 6, 2015||December 12, 2015||Local|
|2015||48||November 29, 2015||December 5, 2015||Local|
|2015||47||November 22, 2015||November 28, 2015||Sporadic|
|2015||46||November 15, 2015||November 21, 2015||Sporadic|
|2015||45||November 8, 2015||November 14, 2015||Sporadic|
|2015||44||November 1, 2015||November 7, 2015||Sporadic|
|2015||43||October 25, 2015||October 31, 2015||Sporadic|
|2015||42||October 18, 2015||October 24, 2015||Sporadic|
|2015||41||October 11, 2015||October 17, 2015||Sporadic|
|2015||40||October 4, 2015||October 10, 2015||Sporadic|
Connecticut Annual Summaries
Weekly national updates are available from the Centers for Disease Control and Prevention's (CDC) FluView website.
International influenza activity is available at the World Health Organization website.
Connecticut's Influenza Surveillance Systems
Hospital Emergency Department Syndromic Surveillance (HEDSS). This system receives daily electronic reports on emergency department visits from more than half of Connecticut's acute care hospitals. Data include a listing of total patient visits with information on their chief complaint, including fever/flu.
Sentinel Provider Surveillance. Reporting of influenza-like illness (ILI) is conducted through a statewide network of volunteer outpatient providers known as ILINet. The proportion of patients exhibiting ILI is reported to the DPH on a weekly basis. ILI is defined as a cough or sore throat in the absence of a known cause, and the presence of a fever greater than 100 degrees Fahrenheit.
Hospital Admissions Syndromic Surveillance (HASS). This system receives daily electronic reports from all 32 acute care hospitals in Connecticut. Information on unscheduled admissions, including those for pneumonia that may be associated with influenza infections, is submitted.
Influenza-associated Hospitalizations. In Connecticut, influenza-associated hospitalizations and deaths are reportable to the DPH. Data collected describe the more serious illnesses associated with influenza infections.
Laboratory Surveillance. Positive influenza tests are laboratory reportable findings in Connecticut. The DPH tracks these results to determine what types, subtypes, and strains are circulating.
Influenza Activity Classification Definitions*
||No laboratory-confirmed cases AND no increase in the number of cases of ILI.|
||Small numbers of lab-confirmed cases OR lab confirmed outbreak in one institution, but NO increase in cases of ILI.|
||Outbreaks of influenza or increases in ILI cases AND recent^ laboratory-confirmed influenza in a single region# of the state.|
||Outbreaks of influenza or increases in ILI cases AND recent laboratory-confirmed influenza in at least 2 but less than half of the regions of the state with recent laboratory evidence of influenza in those regions.|
||Outbreaks of influenza OR increases in ILI cases AND recent laboratory-confirmed influenza in at least half the regions of the state with recent laboratory evidence of influenza in the state.|
*Reporting of influenza-like illness (ILI) is conducted through a statewide network of volunteer outpatient providers known as ILINet.
^Recent is defined as within 2 weeks.
#In general, counties within Connecticut are identified as regions for general data collection and dissemination. The state is also broken down into 5 planning regions by the Division of Emergency Management and Homeland Security (DEMHS). These regions are used by the DPH for influenza surveillance in the event of a novel flu outbreak.
Content Last Modified on 2/11/2016 1:58:42 PM