Imported malaria in Lisbon

Imported malaria is increasing in Western countries, leading to a high mortality rate among severe cases, mainly due to delayed diagnosis and treatment. The authors carried out a 7 years retrospective study (1989-1995) on 205 patients diagnosed with malaria, in the Department of Infectious Diseases, in the Lisbon S. Maria Hospital,. The annual rate was 30 cases per year. Of these patients, 146 (71%) were male, 107 (52%) were black, 121 (59%) lived in endemic malaria areas. The origin of infection was mainly western Africa, Angola being the country with the most cases (47%). Plasmodium falciparum accounted for 93% of the total infections, followed by P. vivax (5%), P. malariae (1%) and P. ovale (0.5%). In 9 patients mixed infections were found (P. falciparum/P. vivax, 6 cases; P. falciparum/P. malariae, 2 cases; P. malariae/P. vivax, 1 case). Only 45 patients (22%) had received malarial prophylaxis. Thrombopenia was the most frequent biological sign (present in 70% of the cases), followed to a lesser degree by LDH elevation, anemia, and liver dysfunction. Nineteen patients (9%) developed severe malaria complications (10 cerebral malaria, 10 renal failure, 2 pulmonary distress, and 2 splenic infarcts). Severe malaria was more frequent in white patients and in those living outside endemic areas. Prior chemoprophylaxis was equally frequent between both groups. Six patients died, the risk of dead being higher among those with multiple organ failure.