Epidemiological study of cutaneous leishmaniasis in Algeria

Cutaneous leishmaniasis is an unstable disease characterized by unpredictable spatio-temporal fluctuations.

This study aimed to identify the main risk factors involved in the persistence of this disease in Algeria.

This study was conducted over 4 years in three regions of the country with different geoclimatic characteristics. The epidemiological features of the disease, its temporal dynamics during the study period, the historical background of the disease in the investigated regions, geoclimatic variations, seasonality, and sandfly abundance were investigated using statistical analyses. The investigations were conducted within the framework of an epidemiological surveillance network between 2019 and 2023. Field missions were conducted out periodically in each study region, combining active case detection in human populations with entomological surveys aimed at identifying and quantifying sandfly species.

Latitude and semi-arid climatic conditions have a significant impact on cutaneous leishmaniasis in Algeria. The disease's endemic character is mainly linked to its historical presence in the affected regions, where it remains stationary. Tebessa recorded the highest mean incidence (919.2 ± 762.5), followed by Annaba (19.2 ± 14.5), whereas Tamanrasset showed the lowest (8.0 ± 5.8). A one-way ANOVA confirmed a statistically significant difference in cutaneous leishmaniasis incidence among the regions (F = 7.05, p < 0.01).

The findings indicate a stable endemic pattern of cutaneous leishmaniasis in all three regions of Algeria, with the highest incidence observed in the semi-arid region of Tebessa. This study highlighted the presence of new factors influencing the endemicity of cutaneous leishmaniasis in certain parts of the world, where effective control requires coordinated interregional or international strategies.