Detection of SFTS Virus in Ixodes nipponensis and Amblyomma testudinarium (Ixodida: Ixodidae) Collected From Reptiles in the Republic of Korea

A survey of reptile-associated ticks and their infection status with severe fever with thrombocytopenia syndrome (SFTS) virus was conducted to determine the relative abundance and distribution among lizards, skinks, and snakes in the Republic of Korea (ROK). In total, 132 reptiles, including 49 lizards (two species), 15 skinks (one species), and 68 snakes (eight species) were collected. In total, 84 ixodid ticks belonging to two genera (Ixodes and Amblyomma) were collected from 28/132 (21.2%) lizards, skinks, and snakes. Ixodes nipponensis Kitaoka & Saito was only collected from lizards and skinks, while Amblyomma testudinarium Koch was only collected from snakes. Takydromus wolteri had the highest tick index (0.7; total number ticks/total number collected hosts) among lizards and skinks, while Rhabdophis tigrinus had the highest tick index (2.2) among the snakes. Ixodes nipponensis larvae and nymphs accounted for 11.1% and 88.9%, respectively, of all ticks collected from lizards and skinks, while only A. testudinarium nymphs were collected from snakes. Nymphs of both species of ticks were collected from lizards and skinks from April to October, while I. nipponensis larvae were collected only from September to October. Ixodes nipponensis larvae and nymphs were preferentially attached to the lateral trunk (83.3%) and the foreleg axillae (16.7%) of lizards and skinks. SFTS virus was detected in both I. nipponensis and A. testudinarium collected from lizards and snakes. Phylogenetic analysis of SFTS viruses of ticks collected from two lizards and one snake demonstrated close relationships with SFTS virus strains observed from humans and ticks in the ROK, China, and Japan. These results implicate lizards and snakes as potential hosts of SFTS virus.