Presence of Antibodies against Severe Fever with Thrombocytopenia Syndrome Virus in Non-Endemic Areas of China

Abstract

To determine the seroprevalence of severe fever with thrombocytopenia syndrome (SFTS) virus (SFTSV) and identify potential risk factors in non-endemic areas, a cross-sectional study was conducted among a healthy population without previously reported SFTS in a mountainous area of Anhui Province. We recruited and collected blood samples from 270 participants in 4 age groups. An enzyme-linked immunosorbent assay kit was used to detect immunoglobulin G (IgG) antibodies against SFTSV. The overall seropositive rate of SFTSV-IgG among study participants was 6.3% (17/270). We found a significant difference in the SFTSV seropositivity rate between tea pluckers (9.4%, 14/149) and non-tea pluckers (2.5%, 3/121). An increasing trend in the seropositivity rate was found with age for all participants (1.5% to 14.3%) and tea pluckers (2.8% to 19.4%). The SFTSV seropositivity rate in men was higher than that in women for all participants and tea pluckers, but the differences were not significant. Critical risk factors for SFTSV infection are increasing age and being a tea plucker. Our findings suggest that health education should be enhanced to increase awareness among residents (especially, the older ones and tea pluckers) to protect them against SFTS.