23 June 2006

 

Norovirus outbreaks on cruise ships

In response to several reports of norovirus outbreaks on board cruise liners, DIVINE-NET, the European network for the prevention of emerging (food-borne) enteric viral infections has launched a European investigation, in collaboration with the European Centre for Disease Prevention and Control (ECDC) [1].

Between 24 April and 9 June 2006, seven cruise ships reported outbreaks of gastroenteritis, with three ships reporting two outbreaks. Norovirus was confirmed as the cause of infection on two ships and samples are being tested from other ships.

Noroviruses are common causes of non-bacterial gastroenteritis and are worldwide in their distribution. Norovirus transmission usually occurs from infected foods, particularly shellfish, from foods contaminated by food-handlers with norovirus infection, from person-to-person, and from contamination of environmental surfaces. Outbreaks of norovirus have been associated in settings where large numbers of people are living in close quarters such as nursing homes, hospitals and cruise ships. Contamination of door handles and railings can contribute to transmission on cruise ships.

Following an incubation period of 12-48 hours, norovirus infection presents with the sudden onset of nausea, vomiting, and non-bloody diarrhoea. Other common symptoms are low-grade fever, headache and myalgias. Norovirus is usually self-limiting and full recovery occurs within 1 - 3 days. However, dehydration requiring medical attention may affect infants and the elderly.

Advice for travellers

The risk of infection with noroviruses can be reduced by good personal hygiene: frequent and thorough hand washing particularly before eating or drinking. Food and water hygiene precautions should also be practised. Treatment of norovirus infection is supportive and includes maintaining hydration.

 

Reference

1. Takkinen J. Recent norovirus outbreaks on river and seagoing cruise ships in Europe. Eurosurveillance. 2006; 11: 2.  [cited 23 June 2006] Available online at http://www.eurosurveillance.org/ew/2006/060615.asp#2

 

Links

DIVINE-NET:

http://www.eufoodborneviruses.co.uk/DIVINEVENT/DIVIndex.asp

NaTHNaC travellers’ diarrhoea information sheet: http://www.NaTHNaC.org/travel/misc/travellers_dir.htm

Centers for Disease for Disease Control and Prevention (CDC) Health Information for International Travel 2005-2006. Norovirus infection: http://www2.ncid.cdc.gov/travel/yb/utils/ybGet.asp?

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