COVID-19 Community Levels Map Update, Jan. 27, 2023: The CDC has listed three Connecticut Counties—Litchfield, Middlesex and New Haven Counties—in the High/Orange category as part of its weekly COVID-19 Community Levels update. Fairfield, Hartford, New London, Tolland and Windham Counties are listed in the Medium/Yellow category.  Because all eight Connecticut counties are either in the High or Medium categories, the Connecticut Department of Public Health recommends that all residents consider wearing a mask in public indoor spaces. People who are at high risk for severe illness should consider additional measures to minimize their exposure to COVID-19 and other respiratory illnesses. Visit the CDC COVID-19 Community Levels Map for updates.

Please visit to request four free COVID-19 self-test kits from the Federal Government. Find a location that has a supply of COVID-19 therapeutics as part of the Test to Treat initiative here. The complete DPH COVID-19 toolbox is located at


Black-legged (Deer) Tick


Babesiosis is mostly caused by a microscopic parasite, Babesia microti. The main way people get babesiosis is through the bite of an infected Black-legged (“deer”) tick (Ixodes scapularis). Although very rare, it is possible for the bacteria to be transmitted through a blood transfusion or from an infected mother to her baby during pregnancy or delivery. Many people who are infected experience no symptoms. When people do get sick from the infection treatment is available; however if it is delayed, or there are underlying medical conditions, symptoms can become more severe. The best way to prevent babesiosis is to prevent tick bites.


About Babesiosis


Information for Clinicians


Clinical Guidance (CDC)


National Surveillance Case Definitions


Connecticut Provider Reporting Information


Connecticut Laboratory Reporting Information


Directory of Clinical Testing Services provided by the State Public Health Laboratory


State Public Health Laboratory Contacts – for additional information


Tick-borne Diseases of the United States – a Reference Manual for Healthcare Providers


Connecticut Babesiosis Surveillance

The Connecticut Department of Public Health (DPH) added babesiosis to the list of state-wide reportable diseases in 1990. The Centers for Disease Control and Prevention established a surveillance case definition in 2011.  Since 2011, an average of 216 cases (range 52 to 311) have been reported to the DPH annually. Babesiosis is the second most commonly reported tick-borne disease in Connecticut. Due to the delay in follow-up, current case counts do not represent all cases of babesiosis.

Connecticut Annual Infectious Diseases Statistics



This page last updated 11/2/2022.