Outbreak of Shigella flexneri 2a infections on a cruise ship

Morbidity and Mortality Weekly Report, Sept 9, 1994

During August 29-September 1, 1994, an outbreak of gastronintestinal illness occurred on the cruise ship Viking Serenade (Royal Caribbean Cruises, Ltd.) during its roundtrip voyage from San Pedro, California, to Ensenada, Mexico. A total of 586 (37%) of 1589 passengers and 24 (4%) of 594 crew who completed a survey questionnaire reported having diarrhea or vomiting during the cruise. One death occurred in a 78-year-old man who was hospitalized in Mexico with diarrhea. Shigella flexneri 2a has been isolated from fecal specimens from at least 12 ill passengers. Antimicrobial susceptibility testing of representative isolates indicated resistance to tetracycline and susceptibility to ampicillin and trimethoprim-sulfamethoxazole. The subsequent two cruises of the ship were canceled. Investigation of the mode of transmission is under way.

Additional information is available from the Vessel Sanitation Program, Special Programs Group, National Center for Environmental Health, telephone (305) 539-6730.

Reported by: Communicable Disease Control, Los Angeles County Dept of Health Svcs; Div of Communicable Disease Control, California Dept of Health Svcs. Foodborne and Diarrheal Diseases Br, Div of Bacterial and Mycotic Diseases, National Center for Infectious Diseases; Vessel Sanitation Program, Special Programs Group, National Center for Environmental Health; Div of Field Epidemiology, Epidemiology Program Office, CDC.