16 June 2006

 

Legionnaires’ Disease in Pamplona, Spain

On 1 June 2006, an outbreak of Legionnaires’ Disease in Pamplona, Navarra, northern Spain was reported to the Public Health Institute of Navarra [1]. As of 14 June 2006, 149 cases have been reported [2], 138 of which were reported in the first week of the outbreak (1-7 June 2006) [3]. Initial cases were all located close to Pamplona city centre. Cooling towers in the area were investigated on 1 and 2 June; four towers tested positive for Legionella and have been closed. Samples from these towers have been sent to the National Centre of Microbiology in Majadahonda, Madrid for typing. On 6 June 2006, low bacterial loads were found in another two cooling towers which have also been closed [1].

In recent years, the European Union (EU) has experienced several large outbreaks of Legionnaires’ Disease [4-6]. In addition, an annual rise in the number of cases and clusters associated with a visit to a hotel or other tourist accommodation site has been identified by the European Surveillance Scheme for Travel Associated Legionnaires’ Disease (EWGLINET) [7-8].

Legionnaires’ Disease is known to be associated with buildings such as hotels where water systems or air conditioning systems sometimes become contaminated with Legionella, the organism that causes the illness in people. Tourists who stay in hotels or other holiday accommodation are therefore a group with a small risk of getting the disease. EWGLINET was established to collect information on these cases in order that measures could be taken to reduce the number of people affected in the short term when outbreaks occur, and in the long term through European prevention programmes. The scheme now receives details of cases from 35 participant countries [8].

When the number of tourists visiting popular holiday destinations is taken into account, the rate of infection per million travellers is very low. In Europe as a whole, infection rates are around nine cases for every million people [9]. However, reporting rates differ between countries and it is assumed that actual rates are probably higher.

All ages can be affected, but Legionnaire’s Disease mainly affects people over the age of 50 and men more than women. If an individual believes they have this infection, they should notify their doctor so that the appropriate investigations can be started. With a rapid diagnosis, antibiotics are effective in treating the disease.

Legionnaires’ disease should be considered as a potential diagnosis for cases of atypical pneumonia throughout the year; however a history of travel during the summer months should act as a specific prompt for clinicians to evaluate for Legionella infection when appropriate symptoms are present.

References

1.Barricarte A, García Cenoz M, Castilla J, Aldaz P. Current legionellosis outbreak with outbreak with 139 cases in Pamplona, Spain. Euro Surveill Weekly. 11(6):060608, 8 June 2006. Available at: http://www.eurosurveillance.org/ew/2006/060608.asp#1  

2. Gobierno de Nevarra. En las últimas 24 horas no se ha producido ningún nuevo caso por el brote de "legionella" registrado en Pamplona, 14 June 2006. Accessed 14 June 2006. Available at: http://www.navarra.es/home_es/Actualidad/Noticias/Salud/1406

sa61.htm

3. Gobierno de Nevarra. 132 afectados por el brote de "legionella" registrado en Pamplona, 7 June 2006. Accessed 14 June 2006. Available at: http://www.navarra.es/home_es/Actualidad/Noticias/Salud/0706

sa61.htm

4. den Boer JW, Yzerman EPF, Schellekens J, et al. A large outbreak of legionnaires’ disease at a flower show, the Netherlands, 1999. Emerg Infect Dis. 8:37-43, 2002.

5. Blystad H, Bjorlow E, Aavitsland P, Holm J. Outbreak of Legionellosis in Stavanger, Norway - final report. Euro Surveill Weekly 5(47):011122, 2001. Accessed 15 June 2006. Available at:

http://www.eurosurveillance.org/ew/2001/011122.asp#2.

6. The European Working Group for Legionella Infections. www.ewgli.org Accessed 15 June 2006.

7. Joseph CA. New outbreak of legionnaires’ disease in the United Kingdom (editorial). BMJ. 325:347-348, 2002.

8. Ricketts KD, McNaught B, Joseph CA. Travel associated legionnaires' disease in Europe: 2004. Euro Surveill 11(4), 2006. Accessed 15 June 2006. Available at: http://www.eurosurveillance.org/em/v11n04/1104-227.asp

9. Ricketts KD, Joseph CA. Legionnaires' disease in Europe 2003-2004.
Euro Surveill. 10(12):256-9, 2005. Accessed 15 June 2006. Available at: http://www.eurosurveillance.org/em/v10n12/1012-226.asp