Detection of Leishmania RNA virus 2 in clinical isolates of Leishmania from Qom Province, Iran.

Leishmaniasis, which is caused by protozoan parasites belonging to the genus Leishmania remains a public-health concern across the provinces of Iran, necessitating better treatments and control strategies. Leishmania RNA virus (LRV) primarily infects Leishmania major and is known to influence disease severity and drug resistance. In this study, we investigated the presence of LRV2 (LRV type 2 in the Old World) in Leishmania isolates from patients with cutaneous leishmaniasis in Qom, Iran, in 2019–2020. Samples from 15 patients were analyzed for species identification using ITS1-PCR-RFLP and for LRV2 detection using RT-PCR, semi-nested PCR, and Sanger sequencing. The viral load was quantified by qRT-PCR. Of the 15 L. major isolates, nine (60%) carried LRV2. Phylogenetic analysis revealed a close relationship to strains previously reported in Golestan province. Given the large number of travelers in Qom, the detection of LRV2 underscores the need for ongoing surveillance and further research into its role in leishmaniasis transmission, clinical outcomes, and drug resistance.