Seasonal dynamics of <i>Haemaphysalis</i> tick species as SFTSV vectors in South Korea

To date, the majority of tick surveillance studies have primarily focused on warmer seasons, which are considered optimal periods for ticks to actively seek hosts and transmit pathogens through blood-feeding activities. Consequently, tick species active during winter have often been overlooked, leading to an underestimation of their significance in transmitting severe fever with thrombocytopenia syndrome virus (SFTSV). In this study, we aimed to examine year-round tick prevalence with SFTSV and illuminate the role of the winter-dominant species, <i>Haemaphysalis flav</i>a, in South Korea. Through rigorous identification facilitated by a primer set designed specifically for this purpose, we emphasize that <i>H. flava</i>, a competent vector species, harbors SFTSV in the winter season, thereby acting as an overwintering reservoir for the virus. This phenomenon may contribute to a higher infection rate among ticks in the following year.