3 August 2007

Respiratory illness associated with cruise ship travel

On 27 July 2007 the Kent Health Protection Unit (HPU), England was alerted to an outbreak of respiratory infection among passengers on the Black Watch Fred Olsen Cruise sailing in the Baltic between 15 July and 1 August 2007 [1]. The ship had 756 passengers and 329 crew on board. On 27 July in Stockholm, seven passengers were transferred from the ship and five were admitted to hospital. Approximately 40 additional passengers reported respiratory symptoms. The cruise was terminated early and arrived in Dover on 30 July. Four passengers were admitted to hospital in England. All hospitalised patients are 70 years or older; there have been no fatalities.

Investigation as to the cause of the passengers’ illness has included taking environmental samples while the ship was in Stockholm and further sampling when the ship arrived in Dover. Preliminary results from Sweden indicate that low levels of Legionella pneumophila were detected in samples taken from the showers in the cabins of two of the hospitalised patients. The results of the water samples taken in England are awaited.

Of the five patients admitted to hospital in Sweden, two have been positive for Legionella by polymerase chain reaction and one by urinary antigen detection.  Urinary antigen tests for Legionella carried out in the UK on 24 passengers with respiratory symptoms have been negative as have been tests on six passengers for influenza A and B. Further testing for other respiratory bacteria and viruses will be performed. Information is also being collected from Sweden with reference to on-shore excursions made by the cases and their use of the spa pools and other water facilities on the ship before they became sick.

Advice for travellers

Legionella predominantly are a cause of pneumonia. While all ages may be affected it is more common in men over the age of 50 years. The bacteria can contaminate a water system or air conditioning unit, and become aerosolized and inhaled while in a spa or taking a shower, as examples. Outbreaks have been well-described in travellers throughout the world including cruise ships [2-6].

All disembarking and embarking passengers have been informed of the incident and provided with advice and information on Legionnaires’ disease, should they become sick. The ship has embarked on its next cruise and spa pools will remain closed until sampling results are known and further advice is given by the UK Health Protection Agency to the ship’s engineers. Physicians who evaluate persons who have been on this cruise ship in July and August and present with respiratory symptoms should consider the diagnosis of Legionnaires’ disease.

References

1. Health Protection Agency. Outbreak of respiratory infection on a cruise ship. Health Protection Report. 1 (31): 3 Aug 2007. On-line resource. Accessed on 3 August 2007. Available at: http://www.hpa.org.uk/hpr/news/default.htm#cruise

2. Ricketts KD, McNaught B, Joseph CA. Travel associated legionnaires' disease in Europe: 2004. Euro Surveill 11(4), 2006. Accessed 3 August 2007. Available at: http://www.eurosurveillance.org/em/v11n04/1104-227.asp

3. Beyrer K, Lai S, Dreesman J, et al. Legionnaires' disease outbreak associated with a cruise liner, August 2003: epidemiological and microbiological findings. Epidemiol Infect 2007;135:802-10.

4. Kura F, Amemura-Maekawa J, Yagita K, et al. Outbreak of Legionnaires' disease on a cruise ship linked to spa-bath filter stones contaminated with Legionella pneumophila serogroup 5. Epidemiol Infect 2006;134:385-91.

5. Regan CM, McCann B, Syed Q, et al. Outbreak of Legionnaires' disease on a cruise ship: lessons for international surveillance and control. Commun Dis Public Health 2003;6:152-6.

6. Castellani Pastoris M, Monaco RL, Goldini P, et al. Legionnaires' disease on a cruise ship linked to the water system: clinical and public health implications. Clin Infect Dis 1999;28:33-8.

Links

The European Working Group for Legionella Infections (EWGLINET): http://www.ewgli.org/ewglinet.htm

NaTHNaC Legionnaires’ Health Information Sheet: http://www.nathnac.org/pro/factsheets/leishmaniasis.htm