May 20, 2022: the Centers for Disease Control and Prevention listed six Connecticut Counties in the High/Orange category as part of its COVID-19 Community Levels Map. Only Fairfield and Tolland Counties are listed in the Medium/Yellow category. Residents in these counties should wear a mask indoors in public; stay up to date with COVID-19 vaccines and get tested if they have symptoms. Additional precautions may be needed for residents who are at high risk for severe illness. Visit the CDC COVID-19 Community Levels Map for updates.


(Legionnaires' disease, Pontiac fever, and extrapulmonary legionellosis)

Legionellosis includes three clinically distinct illnesses, Legionnaires’ disease, Pontiac fever, and extrapulmonary legionellosis, that are all caused by exposure to Legionella bacteria. Legionnaires’ disease most commonly presents as pneumonia. Pontiac fever is a milder, influenza-like illness, and extrapulmonary legionellosis happens when there is disease outside the lungs, (e.g., heart) and diagnostic testing reveals evidence of Legionella at that site.

About Legionella

Surveillance in Connecticut

Information for Patients and the Public

Information for Healthcare Providers and Facilities

Healthcare-Associated Legionnaires' Disease

Epidemiologic Investigation

Environmental Investigation

Information for Building Owners

Water Management Program 


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Legionella  Legionella Activities





This page last updated 3/19/2021.