Malaria must be excluded in all ill patients, particularly in those with fever, who present with a history of travel to malaria-endemic areas, even if appropriate malaria chemoprophylaxis has been used. Other possible aetiologies of fever must also be considered. In non-endemic areas the diagnosis of malaria is a medical emergency and treatment must be initiated urgently. The risk of malaria is highest in tropical Africa. Official guidelines must be followed in all cases of suspected malaria and an infectious disease physician should be contacted for advice. Local laboratory personnel will give advice as regards the samples and investigations required. Malaria is a notifiable infectious disease, and the treating physician is required to report cases in accordance with official guidelines and local practices. Travel to endemic areas necessitates the use of malaria chemoprophylaxis and protection against mosquito bites.