Malaria Prophylaxis

Recommendations for malaria prevention.

Awareness of the risk is essential, before one can effectively act to reduce the risk.
Every attempt should be made to avoid being bitten by mosquitoes. This includes insecticide and repellent use, mosquito nets, and long sleeved clothing between dusk and dawn when most malaria transmission occurs. It has been suggested that transmission rates can be reduced by at least one-tenth, simply by this sensible behaviour.
Chemoprophylaxis must be started one week before departure, in order to identify adverse effects and allow time for the drug to reach appropriate blood concentrations. Additionally, the drug must be continued for four weeks after return to the malaria-free country. As most of the recommended drugs act upon the erythrocytic stage of the parasite, the continuation of prophylaxis allows time to cover the latent, asymptomatic period when the parasite may be residing in the patient's liver, before leaving to invade the red blood cells.
Finally, the last principle urges the traveller to seek medical advice for any fever or flu-like illness during the travel time, or within one year of return, with the aim of early diagnosis and treatment. It must be understood that even if all precautions are taken, and compliance with chemoprophylaxis is good, there still remains an appreciable risk of malaria.

Since the early 1950s, chloroquine has been widely used, providing effective and safe prophylaxis It is safe in pregnancy, and has relatively few side effects or contraindications. Therefore, chloroquine remains the first line choice of chemoprophylaxis in areas of P. falciparum that are sensitive to the drug. Chloroquine is also effective for the three more benign Plasmodium species, with the exception of P. vivax in Oceana, where high-grade resistance has been reported.

Unfortunately, chloroquine's widespread use has resulted in increased resistance, rendering it ineffective against P. falciparum in many areas of the world. In regions of limited to moderate chloroquine resistance, it may be combined with proguanil, another very safe drug, to enhance protection.

Mefloquine, a drug developed during the Vietnam war, is now generally agreed to be the preferred antimalarial for travellers at high risk for chloroquine-resistant P. falciparum.