13 January 2006

Additional cases of Plasmodium falciparum malaria in travellers returning from The Gambia

 

On 8 December 2005, six cases of P. falciparum malaria were reported in holidaymakers returning from The Gambia who became ill in the second half of November 2005 [1]. Two of these cases had died.  Additional cases have been reported since that time [2].

A total of 27 cases with three deaths have now been reported to the HPA Malaria Reference Laboratory with dates of diagnosis between 10 October 2005 and 12 January 2006. Seven out of the eleven cases for whom information is available have required treatment in intensive care units. By comparison, eight cases and one death were reported prior to the current holiday season (Jan - Aug 2005). In the last few years the annual number of cases in people returning from The Gambia has been between 31 and 48 with two or three deaths per year [1].

Of the 27 cases over this winter season to date, 20 were in holiday makers, three in those visiting friends and relatives, and two were travelling for business. For two the reason for travel is not known. Where information is available (n=25), 13 took no prophylaxis, six are known to have taken inadequate prophylaxis and for six, although prophylaxis was taken, it is not known whether this was adequate or not.

The Federation of Tour Operators and Association of British Travel Agents alerted their members to these cases and the need to seek medical care prior to travel. There has also been media coverage [3]. However, the continuing reports of serious malaria show that appropriate preventive measures for malaria are not being observed in all travellers to The Gambia. The winter sun holiday season continues until April so it remains important to reinforce travel health advice.

Advice for travellers

Travellers to The Gambia, as well as to other countries where malaria is endemic, need to plan ahead, seek medical advice, and act on it. Travellers should follow mosquito avoidance measures, particularly in the hours from dusk to dawn, such as wearing clothing that covers exposed skin, applying insect repellent and using bednets [4]. Travellers should also take appropriate malaria chemoprophylaxis. Malaria prevention medicines are often prescription-only and may have to be started up to three weeks before departure.

Travellers who fall ill after a visit to a malarious area should seek prompt medical attention; malaria can present up to a year or more after return [5]. Health care professionals should always take a travel history from anyone with a fever or flu-like illness, and be aware that absence of fever in an ill patient does not exclude the diagnosis of malaria.  If the travel history includes travel to a malarious area, blood film examination should be performed without delay.

Malaria is a notifiable disease.  All malaria cases should be reported to the HPA Malaria Reference Laboratory, with reporting forms available by downloading from the MRL website http://www.malaria-reference.co.uk.

References

1. Health Protection Agency.  Malaria deaths in travellers returning from The Gambia.  Commun Dis Rep CDR Wkly [serial online] 2005 [cited 13 Jan 2006]; 15 (49): news stories.  Available at http://www.hpa.org.uk/cdr/archives/2005/cdr4905.pdf

2. Health Protection Agency.  Further cases of falciparum malaria in travellers returning from The Gambia - update.  Commun Dis Rep CDR Wkly [serial online] 2006 [cited 13 Jan 2006]; 16 (2): news stories.  Available at http://www.hpa.org.uk/cdr/archives/2006/cdr0206.pdf.

3. Renewed warning of malaria risks.  BBC news website. 23 Dec 2005. Available at http://news.bbc.co.uk/1/hi/health/4552920.stm

4. National Travel Health Network and Centre.  Travel Health information sheets: Insect bite avoidance.  [online resource]. Available at http://www.NaTHNaC.org/pro/factsheets/iba.htm

5. Health Protection Agency. Foreign travel-associated illness.  England, Wales, and Northern Ireland - Annual Report 2005. London: Health Protection Agency Centre for Infections; 2005. Available at: http://www.hpa.org.uk/webw/HPAweb&HPAwebStandard/HPAweb_C/1203496904956?p=1158945066450