Objective: Visceral leishmaniasis is an important health problem in Tunisia. The aim of this study was to update the epidemiological and clinical features of the disease.
Design: We performed a retrospective systematic sampling of epidemiological and clinical data collected from the medical records of 1,096 cases of visceral leishmaniasis diagnosed between 1996 and 2006 all over the country.
Results: The mean annual incidence of cases was 99.6 cases/year. The mean annual incidence rate was 1.04 cases/100,000 inhabitants, showing an important increase compared to former studies. As expected, children under 5 years (866 cases) were the most affected with a mean annual incidence rate of 9.6 cases/100,000 (p<0.001). The geographical distribution of cases revealed the spreading of the disease from the Northern parts of the country to the Central and even to Southern ones. Rural cases (65.3%) were significantly more numerous than urban ones (34.7%), p<0.001. The sex ratio was 1.03. The diagnostic delay (average of 54 days) was considerably shortened during the study period compared to previous reports, and explains the decrease of the lethality rate (2.9%).
Conclusions: Visceral leishmaniasis has been present in central Tunisia since the early 1990 s. Its incidence and the distribution area have increased. This evolution is probably linked to the development of irrigation and agriculture favorable to the multiplication of vector sandflies and dogs reservoirs of Leishmania infantum.