International Centre for Cruise Research
A virtual centre for research and for researchers

Dahl, E  "Dealing with gastrointestinal illness on a cruise ship,"
International Maritime Health, 2004, 55(1-4) 19-29

Recent outbreaks of gastrointestinal illness (GI) on passenger ships have caused cruise companies to expand their sanitation programs. 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).  Consecutive GI logs were reviewedfrom 17 cruises of a ship with an average of 590 passengers and 611 crew per day. 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 (57with 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.  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.

Dahl E. "Social status versus formal rank of medical and other officers--an informal survey among passengers and seafarers on cruise ships," International Maritime Health, 2004, 55:1-4, 165-75.

Modern cruise ships have a rigid hierarchic structure, but status of the officers may have changed over time. To get an impression of how cruise officers and crew (=staff) and experienced passengers perceive the status of various shipboard positions, particularly Doctor and Nurse, and compare with present ranks. Passengers and staff during a World Cruise (Ship 1) and staff on a sister-ship (Ship 2) during a voyage without passengers were asked by questionnaire to rank shipboard jobs by assigning 0-4.5 stripes to each position according to perceived social status. Median values were reported. 29% of 109 passengers and 11% of 899 staff responded. Captain was assigned 4.5 stripes by both female and male passengers and staff, followed by Vice Captain (4 stripes, as now, by all). Chief Engineer (4 stripes) was downgraded by male passengers and female staff. Hotel Director (4 stripes) was rated as now by all but male passengers. Executive Housekeeper (2.5 stripes) was upgraded by all but male staff. Doctor (3 stripes) received 4 stripes from passengers and 3.5 from staff. Nurse (2 stripes) got 3 stripes from passengers and 2 stripes from staff. All upgraded Security Officer (2 stripes). The participants seemed to accept the hierarchic rank structure aboard, with the captain alone on top. Marine officers, especially those considered responsible for safety, security and health, were ranked high by all, while passengers also tended to upgrade hotel officers with visible problem-solving positions. Passengers and staff agreed that the Doctor and the Security Officer deserve more stripes, while the Nurses were upgraded by passengers, but not by staff.

Dahl E.  "Passenger mortalities aboard cruise ships,"
International Maritime Health, 2001, 52:1-4, 19-23.

OBJECTIVES: to study the epidemiology of passenger mortalities on cruise ships. METHODS, MATERIAL AND RESULTS: during six years (April 1995 to April 2001) deaths aboard two similar cruise ships (A & B) were registered and studied. Each ship had an average of approximately 800 passengers with median age about 65 years. Twenty five passengers died: 9 men and 3 women on ship A and 10 men and 3 women on ship B. There was an average of one death every six months per ship. More men than women died, although there were more female passengers on both ships (P<0.05). Eleven passengers were found dead in their cabins. Five deaths outside the medical centers were witnessed; four of them had asystole and one ventricular fibrillation when medical staff arrived. Nine patients died after 1/2 to 52 hours of intensive care in the medical centers aboard.

Dahl E.  "Anatomy of a world cruise," Journal of Travel Medicine, 1999, 6:3 (Sept), 168-71.

We registered the patient-related activities of a large cruise ship's medical center during a 103-day worldwide voyage and compared data from 694 passengers (53% women) with median age 66 years with data from 540 crew (27% women) with median age 30 years of age. The medical staff had 3033 (1537 crew, 1496 passenger) consultations (=206 consultations per week) and performed 982 diagnostic procedures. Skin disorders dominated in the crew and were more frequent than in the passengers (29% versus 13%, p<.01), respiratory problems dominated in the passengers and were more frequent than in the crew (26% versus 17%, p<.01), while cardiovascular disorders were more common in the passengers (7% versus 1%, p<.01). Forty-six injuries (35 passengers, 11 crew) were recorded. One passenger died aboard. Seventy-six crew (14%) were not able to work for a total of 110 days (1.1 crew sick per day), while five crew were signed off for medical reasons. To be a doctor or nurse on a large cruise ship during a long sea voyage is no vacation. The medical staff should expect a varied general practice with a higher consultation frequency rate than shoreside, even higher in crew.