Andean cutaneous leishmaniasis (Andean-CL, uta) in Peru and Ecuador: the causative Leishmania parasites and clinico-epidemiological features

- Andean-CL (uta) in Peru distributes at a wide range of the western watersheds of the Andes, while in Ecuador it exists at a limited area of two provinces.
- Principal Leishmania parasites of the disease in Peru and Ecuador are completely different at subgenera level.
- Age and sex differences of the uta-cases in Peru are not clearly defined as found in the past.
- Possible expansion of other Leishmania species to uta-endemic areas than L. (V.) peruviana was discussed, including people's migration.
- Andean-CL in Ecuador is more rural than before, probably because of a rapid development of communities in the endemic area.

ABSTRACTThis study provides comprehensive information on the past and current status of the Andean cutaneous leishmaniasis (Andean-CL, uta) in Peru and Ecuador, mainly focusing on the causative Leishmania parasites and clinico-epidemiological features. Available information and data including our unpublished works were analyzed thoroughly. Endemic regions of the Andean-CL (uta) in Peru run from the north Piura/Cajamarca to the south Ayacucho at a wide range of the Pacific watersheds of the Andes through several departments, while in Ecuador those exist at limited and spotted areas in the country's mid-southwestern two provinces, Azuay and Chimborazo. The principal species of the genus Leishmania are completely different at subgenus level, L. (Viannia) peruviana in Peru, and L. (Leishmania) mexicana and L. (L.) major-like (infrequent occurrence) in Ecuador. The Peruvian uta is now prevalent in different age and sex groups, being not clearly defined as found in the past. The precise reasons are not known and should be elucidated further, though probable factors, such as emergence of other Leishmania parasites, non-immune peoples' migration into the areas, etc., were discussed briefly in the text. The Andean-CL cases in Ecuador are more rural than before, probably because of a rapid development of the Leishmania-positive communities and towns, and the change of life-styles of the inhabitants, including newly constructed houses and roads in the endemic areas. Such information is helpful for future management of the disease, not only for Leishmania-endemic areas in the Andes but also for other endemic areas.

Showing 1) landscape of the Andean-CL (uta) endemic areas La Cuesta/Nambuque, Peru; 2) schematic geographical and altitudinal distribution of the Andean-CL; 3) Vertical distribution of L. (V.) peruviana and other Leishmania spp., in Peru; 4) Vertical distribution of L. (L.) mexicana and L. (L.) major-like and other Leishmania spp. in Ecuador; and 5) different clinical forms, severe in Peruvian adults (above) while very mild in Ecuadorian infants (below).236