Legionellosis Outbreaks Associated with Two Hotels - U.S. Virgin Islands, October 2024-April 2025.

Area of Science:

• Public Health
• Infectious Diseases
• Environmental Health

Background:

• Legionellosis, including Legionnaires disease, is a severe pneumonia caused by Legionella bacteria.
• Travelers can be exposed to Legionella in contaminated water systems, posing a public health risk.
• Two cases of Legionnaires disease among travelers to St. Croix prompted an investigation.

Purpose of the Study:

• To investigate Legionnaires disease cases among travelers in the U.S. Virgin Islands.
• To identify the source of Legionella bacteria exposure and implement control measures.
• To prevent further transmission and outbreaks in tourist destinations.

Main Methods:

• The U.S. Virgin Islands Department of Health (VIDOH) conducted an epidemiological investigation.
• Environmental sampling for Legionella pneumophila was performed at two hotels.
• Water system analysis identified potential sources of bacterial contamination.

Main Results:

• Four cases of legionellosis were identified in travelers aged 53-73.
• Legionella pneumophila was detected in water samples from both hotels, particularly in shower and cold water systems.
• Hotel A required remediation of one room, while Hotel B ceased operations for comprehensive remediation.

Conclusions:

• Outbreaks highlight the need for reporting travel-associated legionellosis for timely public health response.
• Effective water management programs and disinfection are essential, especially in tropical climates where warm temperatures favor Legionella growth.
• Cold water systems in tropical regions require vigilant monitoring and management to prevent Legionella proliferation.