Paraechinus aethiopicus (Ehrenberg 1832) and Atelerix algirus (Lereboullet 1842) hedgehogs: Possible reservoirs of endemic leishmaniases in Tunisia.

Rodents and dogs are the confirmed leishmaniases reservoir hosts in Tunisia. Recently, we described hedgehog Leishmania (L.) major and L. infantum infection in an L. infantum endemic area in the North-West. In order to assess if the observation could extend to other endemic areas and to highlight the potential role of hedgehogs as reservoir host, we aimed here at investigating their Leishmania infection in different foci in Tunisia located along a North-South transect, during and outside different transmission seasons. Based on morphological criteria, 2 hedgehogs' species, Atelerix algirus and Paraechinus aethiopicus were identified. Cytologic analysis showed presence of amastigotes in 9/22 samples corresponding to 4 Atelerix algirus specimens. Also, by combining 3 PCR tests targeting repeated DNA fragments using 13A/13B, Lei70R/Lei70L and nested T2/B4-L1/L4 specific primers, all hedgehogs (N = 12) showed a Leishmania infection. The infection rates were very high on spleen (91.66%), kidney (91.66%), blood (90.90%), liver (83.33%) and eye swabs (100%). Parasites were also detected in peritoneum. Three hedgehogs were found infected with L. infantum and the only Paraechinus aethiopicus specimen with L. major. A mixed L. major and L. infantum infection was identified in 8 animals, while the last one also had an L. tropica infection. Interestingly, 2 animals had skin lesions infected with L. major while all others appeared asymptomatic. There was a correlation between infected status and epidemiological profiles of the localities. Sequences and phylogeny indicated micro-heterogeneity and lack of correlation with sampling, season, or localities. We confirmed natural infection of Atelerix algirus and originally of Paraechinus aethiopicus in Tunisia. High rate of asymptomatic infection, parasitemia, proximity to transmission cycles, epidemiological patterns of infection together with hedgehogs' abundance, lifespan and lifestyle corroborate the hypothesis they constitute reservoir hosts.