Ticks play an important role in transmission
of arboviruses responsible for emerging infectious diseases, and have a significant impact on human, veterinary, and wildlife health. In the
Republic of Korea (ROK), little is known about information regarding the presence
of tick-borne viruses and their vectors. A total
of 21,158 ticks belonging to 3 genera and 6 species collected at 6 provinces and 4 metropolitan areas in the ROK from March to October 2014 were assayed for selected tick-borne pathogens.
Haemaphysalis longicornis (n = 17,570) was the most numerously collected, followed by
Haemaphysalis flava (n = 3317),
Ixodes nipponensis (n = 249),
Amblyomma testudinarium (n = 11),
Haemaphysalis phasiana (n = 8), and
Ixodes turdus (n = 3). Ticks were pooled (adults 1–5, nymphs 1–30, and larvae 1–50) and tested by one-step reverse transcription polymerase chain reaction (RT-PCR) or nested RT-PCR for the detection
of severe fever with thrombocytopenia virus (SFTSV), tick-borne encephalitis virus (TBEV), Powassan virus (POWV), Omsk hemorrhagic fever virus (OHFV), and Langat virus (LGTV). The overall maximum likelihood estimation (MLE) [estimated numbers
of viral RNA positive ticks/1000 ticks] for SFTSV and TBEV was 0.95 and 0.43, respectively, while, all pools were negative for POWV, OHFV, and LGTV.
The purpose of this study was to determine the prevalence of SFTSV, TBEV, POWV, OHFV, and LGTV in ixodid ticks collected from vegetation in the ROK to aid our understanding of the epidemiology of tick-borne viral diseases. Results from this study emphasize the need for continuous tick-based arbovirus surveillance to monitor the emergence of tick-borne diseases in the ROK.
