Imported malaria (1985-95): trends and perspectives

Abstract

Malaria is frequently imported into nonendemic industrialized areas. In this study we collated data on the reported malaria cases in industrialized countries during the period 1985-95, with the object of identifying trends and promising strategies. The main outcome measures were incidence, case-fatality rates (CFRs), and attack rates in tourists returning from Kenya. Our survey showed gross underreporting and marked heterogeneity in the type and availability of national data. The total incidence or reported numbers of malaria infections in Europe increased from 6840 in 1985 to 7244 in 1995, with a peak of 8438 in 1989. The principal importing countries were France, Germany, Italy, and the United Kingdom. In the former USSR, the reported annual incidence dropped from 1145 in 1989 to 356 in 1990 after cessation of activities in Afghanistan. Among the imported species of malaria parasite, Plasmodium falciparum was identified in an increasing proportion, the CFR ranging from 0% to 3.6%, with consistently high rates in Germany. The attack rates among travellers to Kenya in 1990-95 were high, ranging from 18 to 207 per 100,000 travellers. Our findings indicate that in industrialized countries malaria is associated with a high CFR and remains a public health problem. Irregular surveillance and lack of homogeneity in the collected data hinder the assessment of incidences, risk groups, and the efficacy of chemoprophylaxis.