Work

Evaluation of an Italian Phlebotomus perfiliewi (Larroussius) wild population as a permissive vector species for Leishmania tropica and L. major transmission

Year: 2025

Type: article

Abstract: BACKGROUND: Among pathogenic Leishmania species, L. major and L. tropica, occur mainly in North African and Middle Eastern countries, primarily transmitted by Phlebotomus papatasi and P. sergenti respectively. In Italy, P. perfiliewi is the second most abundant sand fly species involved in L. infantum transmission exhibiting opportunistic behaviour in rural and semi-urban settings. Experimental infections were conducted to assess the susceptibility of a wild Italian P. perfiliewi population to the development of L. tropica and L. major. METHODS: promastigotes/ml). Infection progression was monitored through microscopic midgut dissection and supported by molecular analyses. RESULTS: Experimental infections with L. tropica yielded 5923 engorged females, with an average feeding rate of 25.7% and a survival rate of 70%. The infection positivity rate was 25.2%, significantly lower than that observed in the control species. Nonetheless, parasite migration to the stomodeal valve suggests that P. perfiliewi may support the full developmental cycle of L. tropica, although less efficiently than the control species. Infections with L. major showed a significantly lower mean feeding rate (p = 0.05) and a positivity rate of 46.6%, compared to 70.5% in P. perniciosus (p = 0.03). Still, P. perfiliewi appeared capable of supporting L. major metacyclogenesis, even under light to moderate parasite loads (p = 0.007). CONCLUSIONS: These findings suggest that P. perfiliewi can support the development of both L. tropica and L. major under experimental conditions, with greater susceptibility observed for L. tropica. However, without in vivo confirmation or xenodiagnosis, its capacity for natural transmission remains unestablished. Nonetheless, implementing integrated One Health surveillance strategies would be advisable to monitor potential changes in the epidemiology of both exotic and endemic Leishmania species.

Source: Parasites & Vectors

DOI: 10.1186/s13071-025-07170-7