The Discovery Process of SFTS in China

Heightened surveillance of acute febrile illness in China since 2004 led to the identification of a severe fever with thrombocytopenia syndrome (SFTS) with unknown etiology. Sporadic patients hospitalized with SFTS in 2009 and 2010 were identified and serum samples were collected. Sequence from a novel species of phlebovirus was identified by sequence independent single primer amplification (SISPA) from the serum of a patient with SFTS. The virus was isolated in Vero cell culture and its complete genome sequence was determined, only distantly related to other known phleboviruses. Electron microscopic analysis revealed a virion morphologically characteristic of phleboviruses. The virus was named as SFTS virus. The viral RNA and/or specific antibodies were detected from the blood of patients with SFTS. Serological assays demonstrated a virus-specific immune response in pairs of sera collected from patients at acute and convalescent phases. The pathogenic mechanisms of thrombocytopenia in human SFTS disease was resembled in a mouse model. The results had been collected to demonstrate that SFTS virus was etiologically associated with an acute and novel infectious disease, SFTS in humans.