Research Advances on Epidemiology of Severe Fever with Thrombocytopenia Syndrome: A Systematic Review of the Literature

Cheng-Yang Hu, Le Ouyang, Li-Y

Abstract

Severe Fever with Thrombocytopenia Syndrome (SFTS) is an emerging infection disease caused by SFTSV, a newly discovered bunyavirus. Suspected SFTS cases were first reported in 2006 in Anhui province, China and SFTSV was first isolated in 2009 in Henan province, China. The disease has been reported in more than 23 provinces in central and eastern China and it was also reported in South Korea and Japan. SFTS is a hemorrhagic fever with major clinical manifestations of fever, thrombocytopenia, gastrointestinal symptoms and leucopenia. In severe SFTS patients, the clinical conditions may proceed quickly and result in multi-organ failure. The average case fatality rate was approximately 10% in humans. The incidence rate of SFTS was significantly higher in old age people and fatal cases mainly occurred in elderly people. SFTS is most likely to be transmitted by tickbite and it also can be transmitted from person to person. The potential reservoir hosts of SFTSV including goats, dogs, cattle, chicken and even birds. This article reviews the latest advances on SFTS epidemiology characteristics including risk factors, sources of infection, distribution of SFTS cases, transmission route and aetiological characteristics, laboratory testing, clinical symptoms, susceptible population, relationship between the meteorological factors and SFTS.