Viral shedding from diverse body fluids in a patient with severe fever with thrombocytopenia syndrome

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne disease characterized by high fever, thrombocytopenia, leukopenia, and multiple organ failure and is caused by a novel bunyavirus. Human-to-human transmission has been reported previously, but the mode of transmission has not been clarified thoroughly. Study design: We identified a case of a 73-year-old woman with SFTS and performed a semi-quantitative real-time reverse transcription PCR (real-time RT-PCR) assay on her blood, tracheal aspirate, gastric aspirate and urine to detect SFTS virus (SFTSV). Results: During 7-day hospitalization, all the serum samples showed positive C_t values lower than 35 in both the S and M segments, suggesting the presence of the SFTSV RNA. After initiation of plasma exchange, serum SFTSV load markedly decreased, but still remained positive. The SFTS viral RNA was also detected in other body fluids, including tracheal aspirate and gastric aspirate. Conclusion: These results suggest that droplet transmission can occur through close contact with infected patients.