Current status of severe fever with thrombocytopenia syndrome in China

Abstract

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by SFTS virus (SFTSV). SFTSV is associated with a high mortality rate and has been reported in China, South Korea and Japan. SFTSV undergoes rapid changes owing to evolution, gene mutations, and reassortment between different strains of SFTSV. In this review, we summarize the recent cases and general properties of SFTS, focusing on the epidemiology, genetic diversity, clinical features, and diagnostics of SFTSV in China. From 2010 to October 2016, SFTS cases were reported in 23 provinces of China, with increased numbers yearly. Infection and death cases are mainly found in central China, where the Haemaphysalis longicornis ticks are spread. The national average mortality rate of SFTS infection was 5.3%, with higher risk to elder people. The main epidemic period was from May to July, with a peak in May. Thus, SFTS reminds a significant public health problem, and development of prophylactic vaccines and effective antiviral drugs will be highly needed.

Genomes and seroprevalence of severe fever with thrombocytopenia syndrome virus and Nairobi sheep disease virus in Haemaphysalis longicornis ticks and goats in Hubei, China

“…Due to a lack of any prophylactic vaccine or effective antivirals, the mortality rate of SFTS cases can reach as high as 30%. SFTS has therefore become a significant public health problem (Liu et al, 2014b;Zhan et al, 2017). Beyond China, SFTS has also been reported in Japan and South Korea in 2013, with a similar case reported in the USA in 2012 (Kim et al, 2013;McMullan et al, 2012;Takahashi et al, 2014), indicative of a potentially global situation requiring control and prevention.…”

“…Currently, almost 10,000 cases of the disease have been reported in 23 provinces and etiologically confirmed in 18 provinces, with numbers increasing yearly ( Fig. 1) (Liu et al, 2014b;Zhan et al, 2017). Due to a lack of any prophylactic vaccine or effective antivirals, the mortality rate of SFTS cases can reach as high as 30%.…”

Cutaneous histopathology of the tick‐bite region in severe fever with thrombocytopenia syndrome

“…Similar viruses have been reported in Japan, Korea and the USA . Although the transmission hosts and vectors remain unclear, the long‐horned tick ( Haemaphysalis longicornis ) is considered the most likely transmission vector . The mechanisms of entry for SFTSV into the patient from a tick‐bite region are not yet fully understood.…”

“…In 2009, an emerging infectious disease was reported in China, with major clinical symptoms of fever, thrombocytopenia and leukocytopenia, and a mortality rate of 6–30% . This disease was designated “severe fever with thrombocytopenia syndrome” (SFTS).…”

Severe Fever with Thrombocytopenia Syndrome

“…Regarding the vaccine have published a paper attempting to identify optimal strains for vaccines from the eight main strains of SFTS virus strains in China [3]. According to that paper, it is concluded that HB 29 strain will be optimal as a standard strain for vaccines because of its strong cross-reactivity with heterologous antibodies and high homology in the S segments with other SFTS virus strains.…”