The initial detection of Toscana virus in phlebotomine sandflies from Turkey

• Published in: Medical and veterinary entomology 2020-12, Vol.34 (4), p.402-410
• Main Authors: Özbel, Y., Oğuz, G., Arserim, S. K., Erişöz Kasap, Ö., Karaoglu, B., Yilmaz, A., Emanet, N., Günay, F., Hacioğlu, S., Demirok, M. C., Töz, S., Alten, B., Nalçaci, M., Özkul, A., Ergünay, K.
• Format: Article
• Language: English
• Subjects: Amino acid substitution; Animals; Bunyaviridae Infections - transmission; Central nervous system; Genotypes; Humans; Insect Vectors - parasitology; Insect Vectors - virology; Leishmania; Leishmania tropica - isolation & purification; Leishmaniasis, Cutaneous - transmission; phenuiviridae; Phlebotomus - classification; Phlebotomus - parasitology; Phlebotomus - virology; phlebovirus; Phylogeny; Psychodidae - classification; Psychodidae - parasitology; Psychodidae - virology; RNA, Viral; sandfly; Sandfly fever Naples virus - genetics; Sandfly fever Naples virus - isolation & purification; Toscana virus; Turkey - epidemiology; Vector Borne Diseases - parasitology; Vector Borne Diseases - transmission; Vector Borne Diseases - virology; Vectors
• ISSN: 0269-283X; 1365-2915
• DOI: 10.1111/mve.12450

Toscana virus (TOSV) is a prominent arthropod‐borne viral agent of human central nervous system infections occurring in the Mediterranean region. The main transmission route to susceptible individuals involves sandflies as vectors. Despite several reports revealing widespread TOSV activity in Turkey, vectors remained unidentified. A sandfly field survey was carried out in five provinces in Central, Southeast and Mediterranean Anatolia in 2017 to identify TOSV and related sandfly‐borne phleboviruses and Leishmania parasites, with evidence for circulation in the region. A total of 7136 sandfly specimens, collected via standard methods, were evaluated in 163 pools. TOSV was detected in 11 pools (6.7%), comprising Phlebotomus major sensu lato, Sergentomyia dentata and Phlebotomus papatasi species. TOSV partial L and S segment sequences were characterized, that phylogenetically clustered with local and global genotype A strains. An amino acid substitution outside the conserved motifs of the viral polymerase, also present in previous TOSV sequences in endemic regions, was observed. Leishmania tropica was detected in a single pool of Ph. sergentii (0.6%). This is the first report of TOSV in sandflies from Turkey, and this study further provides evidence for additional sandfly species with the potential to transmit TOSV. We detected Toscana virus (TOSV) RNA in field‐collected sandflies from various regions of Anatolia, as well as Leishmania tropica. TOSV‐infected sandflies were identified as Phlebotomus major sensu lato, Phlebotomus papatasi and Sergentomyia dentata. Partial L and S segment sequences phylogenetically‐clustered with genotype A strains, with an amino acid substitution in the viral polymerase.