Hard Ticks as Vectors Tested Negative for Severe Fever with Thrombocytopenia Syndrome in Ganghwa-do, Korea during 2019-2020

This study aimed to characterize the seasonal abundance of hard ticks that transmit severe fever with thrombocytopenia syndrome virus from April to November 2019 and 2020 on Ganghwa-do, Incheon Metropolitan City, Korea. The ticks were collected at grassland, grave site, copse and mountain road using a collection trap method. The ixodid hard ticks comprising three species (Haemaphysalis longicornis, H. flava, and Ixodes nipponensis) collected were 6,622 in 2019 and 3,811 in 2020. H. longicornis was the most frequent (97.9% in 2019 and 96.0% in 2020), followed by H. flava (2.0% and 3.0% in 2019 and 2020, respectively) and I. nipponensis (less than 0.1%). Our study demonstrated that seasonal patterns of the tick populations examined for two years were totally unsimilar. The hard ticks tested using RT-qPCR were all negative for severe fever with thrombocytopenia syndrome virus.