부산대학교 도서관

Human African Trypanosomiasis (HAT) in West Africa is a lethal, neglected disease caused by Trypanosoma brucei gambiense transmitted by the tsetse Glossina palpalis gambiensis. Although the littoral part of Guinea with its typical mangrove habitat is the most prevalent area in West Africa, very few data are available on the epidemiology of the disease in such biotopes. As part of a HAT elimination project in Guinea, we carried a cross-sectional study of the distribution and abundance of people, livestock, tsetse and trypanosomes in the focus of Boffa. An exhaustive census of the human population was done, together with spatial mapping of the area. Entomological data were collected, a human medical survey was organized together with a survey in domestic animals. In total, 45 HAT cases were detected out of 14445 people who attended the survey, these latter representing 50.9% of the total population. Potential additional carriers of T. b. gambiense were also identified by the trypanolysis test (14 human subjects and two domestic animals). No trypanosome pathogenic to animals were found, neither in the 874 tsetse dissected nor in the 300 domestic animals sampled. High densities of tsetse were found in places frequented by humans, such as pirogue jetties, narrow mangrove channels and watering points. The prevalence of T. b. gambiense in humans, combined to low attendance of the population at risk to medical surveys, and to an additional proportion of human and animal carriers of T. b. gambiense who are not treated, highlights the limits of strategies targeting HAT patients only. In order to stop T. b. gambiense transmission, vector control should be added to the current strategy of case detection and treatment. Such an integrated strategy will combine medical surveillance to find and treat cases, and vector control activities to protect people from the infective bites of tsetse. Author Summary: Human African Trypanosomiasis (HAT) in West Africa is a lethal, neglected disease caused by Trypanosoma brucei gambiense transmitted by the tsetse fly Glossina palpalis gambiensis. Although the littoral part of Guinea with its typical mangrove habitat is the most prevalent area in West Africa, very few data are available on the epidemiology of the disease in such biotopes. We carried out a cross-sectional study of the distribution and abundance of people, livestock, tsetse and trypanosomes in the active focus of Boffa. We only found T. b. gambiense in the area, no other trypanosome. T. b. gambiense was found parasitologically in humans (45 cases), and suspected serologically in other humans and in two animals. Tsetse flies were present in high densities in places very frequented by humans, such as pirogue jetties, and watering points. Our results confirm the importance of medical surveys to find cases and treat them, but also point out the limit of strategies targeted at HAT patients only. If sleeping sickness is to be eliminated, a vector control component must be added to the strategy of case detection and treatment, and this latter must be directed to the population the most at risk. [ABSTRACT FROM AUTHOR]