30 April 2008
Falciparum malaria in a German tourist, acquired on Great Exuma, Bahamas, March 2008
A woman in her fifties was treated for falciparum malaria at the University Medical Centre in Hamburg, Germany in April 2008.
The patient had been on a three week holiday on the Bahamas (George Town, Great Exuma and Nassau, New Providence) in mid-March 2008. One week after her return to Germany, she developed high fever for about two days and was treated with antipyretics by her general physician. The symptoms improved gradually, but seven days later she presented to a local hospital with ongoing headaches, fever and a reduced general condition.
Treatment with corticosteroids was initiated for the assumed diagnosis of temporal arteriitis , but her symptoms persisted. Six days later, follow-up investigations included examination of a thick film, which revealed a Plasmodium falciparum infection with a parasitaemia of circa 1%. She was then transferred to the University Medical Centre in Hamburg. When asked about her past travel history she declared not to have travelled to any countries endemic for malaria other than the Bahamas.
Laboratory evaluation showed a normocytic regenerative anaemia (haemoglobin 9.6 g/dl, reticulocytes 4.7%), an elevated lactate dehydrogenase activity of 279 U/l and slightly elevated alanine transaminase activity of 41 U/l. A chest X-ray did not show any pathological findings. Abdominal ultrasound examination revealed a mild splenomegaly (136 x 68 mm). Her initially depleted thrombocytes had returned to normal after the steroid treatment.
Treatment with chloroquine was started following the recommendations of the German Society for Tropical Medicine and International Health (DTG) (25 mg/kg bodyweight divided over three days). Fever, headache and malaise resolved within two days, all laboratory parameters returned to normal within one week of treatment. On hospital discharge, no parasites were detectable in thick films.
Although the Bahamas are considered free of malaria, there have been outbreaks of falciparum malaria on the island of Great Exuma during the last few years. 18 patients were diagnosed with falciparum malaria in 2006, two in 2007 [1,2,3,5]. Examination of the cohort of 2006 revealed a community of immigrants from Haiti – where P. falciparum is endemic – as the most probable source of infection. Twenty-nine of 159 Haitians living on Great Exuma tested positive for P. falciparum  and mass treatment with chloroquine and primaquine was initiated.
This case is the second reported falciparum malaria originating from the Bahamas in 2008. The first was a Canadian traveller in January 2008 . These two new cases resulted in a reintroduction of the United States Centers for Disease Control and Prevention's recommendation to use chloroquine as prophylactic treatment when travelling to Great Exuma .
The risk of acquiring falciparum malaria on the Bahamas must not be underestimated, as there are reports of several cases each year. Still, the risk for tourists can be considered to be very low.
Except for the protection from mosquito bites and the advice to contact a doctor when developing fever, further recommendations regarding prophylaxis for travellers to the Bahamas do not, in our opinion, appear necessary at this point in time.
1. No authors listed. Outbreak news. Malaria, Bahamas. Wkly Epidemiol Rec. 2006 Jun 23:81(25):241.
2. Centers for Disease Control and Prevention. Malaria in the Bahamas: Recommendations for travelers. Outbreak notice. 23 August 2007. Accessed 24 August 2007. Available from: http://www.cdc.gov/travel/contentMalariaBahamas07.aspx
3. Centers for Disease Control and Prevention. Malaria, Great Exuma, Bahamas: Recommendations for Travelers. Outbreak Notice. 1 August 2006. Accessed 11 August 2006. Available from: http://www.cdc.gov/travel/other/2006/malaria_bahamas.htm
4. Pro-MED-mail. Malaria in a Canadian Forces member, likely acquired in Great Exuma, Bahamas. ProMED-mail 2008; 17 April: Archive no. 20080417.1380. Available from: http://www.promedmail.org
5. Centers for Disease Control and Prevention (CDC). Malaria—Great Exuma, Bahamas, May-June 2006. MMWR Morb Mortal Wkly Rep. 2006 Sep 22;55(37):1013-6.
6. Centers for Disease Control and Prevention (CDC). Outbreak Notice. Reinstatement of Malaria Recommendations for Great Exuma, Bahamas. 17 April 2008. Available from: http://wwwn.cdc.gov/travel/contentMalariaBahamas07.aspx