Seroprevalence of Severe Fever with Thrombocytopenia Syndrome Virus Antibodies in Rural Areas, South Korea

Abstract

We investigated 1,228 residents of 3 rural areas in South Korea and determined that 50 (4.1%) were positive for severe fever with thrombocytopenia syndrome virus antibodies. Fever and gastrointestinal symptoms in the previous 3 years and career duration were associated with virus seropositivity.

Keywords: SFTS; SFTSV; South Korea; antibodies; rural areas; seroprevalence; severe fever with thrombocytopenia syndrome; severe fever with thrombocytopenia syndrome virus; ticks; vector-borne infections; viruses.

Figure 1

Seroprevalence in 3 rural areas (2014) and incidence in 8 provinces (2013–2014) of severe fever with thrombocytopenia syndrome, South Korea. Within each province, 1 rural area was selected on the basis of the number of cases. Green circles indicate seroprevalence determined by using an indirect immunofluorescence assay. The incidence rate is per 1 million persons.

Figure 2

Representative indirect immunofluorescent assays of Vero E6 cells infected with thrombocytopenia syndrome virus from patients in rural areas, South Korea. Indirect immunofluorescent assays were conducted by using serially diluted patient serum as primary antibody and fluorescein isothiocyanate–conjugated antihuman IgG as secondary antibody. A) H1 serum (negative, dilution 1:32, IgG titer <1:32); B) B321 serum (positive, dilution 1:64, IgG titer 1:512); C) H214 serum (positive, dilution 1:32, IgG titer 1:128); D) D127 serum (positive, dilution 1:32, IgG titer 1:256). Original magnification x400.