The first molecular evidence of severe fever with thrombocytopenia syndrome virus in ticks in Jilin, Northeastern China

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne zoonosis. The aim of this study was to investigate SFTS virus (SFTSV) infections in ticks in Northeastern China. A total of 6427 ticks, including 5450 Haemaphysalis longicornis, 463 Dermacentor silvarum, 351 Dermacentor nuttalli, and 163 Ixodes persulcatus, were sampled in the Liaoning, Jilin, and Heilongjiang Provinces of Northeastern China. Viral megagenomic analysis of the ticks revealed 25 contigs targeting the M and L segments of the SFTSV genome. H. longicornis collected from Jinxing, Jilin Province, were analyzed by RT-PCR, which showed positive results for SFTSV, with a minimum prevalence of 3.0%. The full-length sequence of the S, M, and L segments of the SFTSV were obtained, and phylogenetic analysis showed that the virus strain found in Jilin formed a monophyletic cluster with the SFTSV strains from Jiangsu, suggesting that SFTSV in the Jilin Province may have spread from the Jiangsu Province. These findings are the first to demonstrate molecular evidence of SFTSV in ticks in the Jilin Province of Northeastern China and indicate the need for measures to prevent and control SFTS.