Malaria at Christmas: risks of prophylaxis versus risks of malaria

A large increase in the number of falciparum malaria cases imported into the UK was reported to the malaria reference laboratory in the first quarter of 1998. Contributory factors were unusually heavy rains in east Africa and a reduction in the use of the most effective antimalarial drug, mefloquine. There was also an increase in the number of cases of severe malaria in the UK. During December 1997 and January 1998, the Hospital for Tropical Diseases, London, treated 5 patients for severe malaria and gave advice on 20 more patients with malaria who had been admitted to intensive care units throughout England. 4 of the severe cases treated at the hospital are reported. In 3 of those 4 cases, incorrect, misleading, or inadequate advice was given by health care professionals. Media coverage of the adverse effects of antimalarial drugs has contributed to confusion about prophylactic regimens among both health care professionals and the public. The incidence of falciparum malaria among travellers who do not take prophylactic drugs is about 0.6% in east Africa and 3.5% in west Africa over a 2-week travel period. Travellers need to take measures to avoid being bitten by mosquitoes and should be taught to promptly seek medical help if they develop a fever while abroad or after they return. Moreover, using any one of the recommended prophylactic regimens is better than not using a potent regimen or no prophylaxis at all. Mefloquine is 90% protective against malaria in sub-Saharan Africa. While the efficacy of proguanil and chloroquine in 1987 was about 70% in west Africa and 50% in east Africa, those levels are now probably lower. The side effects of antimalarial drugs are discussed.