The Connecticut Department of Public Health (CT DPH) began routine legionellosis surveillance in 1997. Since then, annually reported cases have ranged from 15-201. An upward trend in recent years shows monthly and seasonal variation as seen in the figure below. The CT DPH uses the national surveillance case definition to determine case status. Legionellosis is reportable to the CT DPH by physicians and laboratories, and to the patient’s local health department. To identify possible common sources of exposure, staff of the CT DPH Epidemiology and Emerging Infections Program conduct follow-up on all confirmed legionellosis cases by contacting the healthcare provider of record, and conducting patient interviews.
This page last updated 12/13/2021.