First case of laboratory-confirmed severe fever with thrombocytopenia syndrome disease revealed the risk of SFTSV infection in Xinjiang, China

Abstract

The Xinjiang Uygur Autonomous Region locating in Northwest of China was not considered the epidemic area of severe fever with thrombocytopenia syndrome (SFTS). Here we report the first laboratory-confirmed SFTS case that a female patient had tick bite in Xinjiang and illness onset after returning to Hainan Province. Laboratory tests identified SFTS virus (SFTSV) infection, and the virus was isolated from the patient's serum sample. Furthermore, SFTSV prevalence among tick groups was identified, and IgM response to SFTSV from febrile patients was identified. The findings suggested that there have been risks of SFTSV infection due to exposure to ticks in Xinjiang.

Keywords: Severe fever with thrombocytopenia syndrome virus; Xinjiang; exposure to ticks; first laboratory-confirmed case; virus isolation.

Figure 1.

(a) A map presenting the patient’s travelling routes in Xinjiang and (b) the timeline of important events before illness onset and during hospitalization. The green star represents the grasslands and the green triangle indicates the location of poplar tree forest. KNS, Kanas resort; URQ, Urumqi City; HJ, Hejing County; KL, Korla City; BKG, Bayanbulak Grassland; YL, Yuli County. XJ, Xinjiang Uygur Autonomous Region; HN, Hainan Province. (c) The images of one tick found from the patient’s hair (left) and the papules noted on her scalp (right) were taken by using a mobile phone (HUAWEI EVA-AL10). (d) SFTSV particles observed by negative staining electron microscopy. Bar, 200 nm. (e) The maximum likelihood phylogenetic trees were created based on the complete sequences of the L (left), M (middle) and S (right) segments, respectively. The branches of genotypes are indicated by colours. The isolated virus strain XJ/HN2017 is labelled with a red solid circle. Trees were constructed using Mega 5.0 and tested by bootstrap method of 1000 replicates. Bootstrap values >50% are shown at each node.

Figure 1.

(a) A map presenting the patient’s travelling routes in Xinjiang and (b) the timeline of important events before illness onset and during hospitalization. The green star represents the grasslands and the green triangle indicates the location of poplar tree forest. KNS, Kanas resort; URQ, Urumqi City; HJ, Hejing County; KL, Korla City; BKG, Bayanbulak Grassland; YL, Yuli County. XJ, Xinjiang Uygur Autonomous Region; HN, Hainan Province. (c) The images of one tick found from the patient’s hair (left) and the papules noted on her scalp (right) were taken by using a mobile phone (HUAWEI EVA-AL10). (d) SFTSV particles observed by negative staining electron microscopy. Bar, 200 nm. (e) The maximum likelihood phylogenetic trees were created based on the complete sequences of the L (left), M (middle) and S (right) segments, respectively. The branches of genotypes are indicated by colours. The isolated virus strain XJ/HN2017 is labelled with a red solid circle. Trees were constructed using Mega 5.0 and tested by bootstrap method of 1000 replicates. Bootstrap values >50% are shown at each node.