Dealing with gastrointestinal illness on a cruise ship--Part 1: Description of sanitation measures. Part 2: An isolation study.

BACKGROUND: Recent outbreaks of gastrointestinal illness (GI) on passenger ships have caused cruise companies to expand their sanitation programs.

OBJECTIVES: To describe sanitation procedures and measures involving the medical staff of one cruise ship (Part 1), and to show how one of the new measures, isolation, influenced medical practice (Part 2).

METHODS: Consecutive GI logs were reviewed from 17 cruises of a ship with an average of 590 passengers and 611 crew per day.

RESULTS: During a 250-day period 207 persons were isolated for a total of 419 days: 113 passengers (75 with GI, 38 asymptomatic contacts) and 94 crew (57 with GI, 37 contacts). The percentage of GI cases per 7 days varied between 0.10% and 0.43% among passengers and between 0 and 0.39% among crew, except for one cruise when the percentage per 7 days reached 2.16% among passengers and 0.61% among crew.

CONCLUSIONS: A detailed operational directive for all aspects of sanitation is helpful for prevention and control of GI outbreaks on ships. A strict isolation policy is an expensive, but critical measure, which in particular challenges the medical staff.