Prevalence of severe fever with thrombocytopenia syndrome virus in Haemaphysalis longicornis ticks in South Korea.

Haemaphysalis longicornis a vector that harbors severe fever with thrombocytopenia syndrome virus (SFTSV) is a major species of tick in South Korea. To investigate the existence and prevalence of SFTSV in Korea, we collected ticks from nine provinces in South Korea for detecting SFTSV. In all, we collected 13,053 ticks, and H. longicornis (90.8%, 11,856/13,053) was the most abundant among them. The minimum infection rate (MIR) of SFTSV in H. longicornis was 0.46% (55 pools). SFTSV was detected in ticks during all the developmental stages, showing MIR in larvae (2/350, 0.57%), nymphs (38/10,436, 0.36%), males (2/221, 0.90%), and females (13/849, 1.53%), respectively. Viruses were detected in ticks collected between April and September. A higher MIR was detected in ticks from the southern part of the country. We amplified the M and S segment partial genes from a sample and analyzed the nucleotide sequence. The results showed a 93-98% homology to Chinese and Japanese strains registered in Genbank. In this study, we confirmed the existence of SFTSV for the first time in South Korea. The SFTSV prevalence data from the studies are essential for raising the awareness of SFTS in South Korea.