Pathogen Isolation and Traceability Analysis of a Fatal Case of Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV) Infectious Encephalitis in China

Overview

Journal Virol J

Publisher Biomed Central

Specialty Microbiology

Date 2024 Nov 23

PMID 39578877

Authors

Rongjiao Liu

Fangling He

Shengbao Chen

Juan Wang

Chan Yang

Zhifei Zhan

Yaru Xiong

Liang Cai

Affiliations

Soon will be listed here.

Abstract

Background: The initial clinical symptoms of severe fever with thrombocytopenia syndrome (SFTS) mainly include high fever, thrombocytopenia and gastrointestinal symptoms, and severe patients may suffer from severe complications such as multiple organ failure, which can lead to death. Studies have shown that central nervous system symptoms are associated with severe adverse outcomes of SFTS, but there are few reports on confirmed cases of SFTS encephalitis. This is a special case in which her initial SFTS symptoms were atypical, while the disease deteriorated rapidly after the appearance of encephalitis. The purpose of this study was to report the clinical and epidemiological features of this case, isolate and trace the SFTS virus (SFTSV) strain, identify the genotype of the strain, and speculate on the infection route to provide an important reference for the diagnosis and control of SFTSV.

Methods: Cerebrospinal fluid and serum samples were collected, multipathogen detection was performed via next-generation sequencing (NGS), and SFTSV virus isolation was performed via inoculation of the samples with Vero cells. The serum of key populations closed to patients, parasitic ticks on the surface of domestic animal bodies and environmentally free ticks were collected for SFTSV monitoring. The whole genomes of the virus strains and positive nucleic acid samples were sequenced and compared with the GenBank reference sequence to construct a phylogenetic analysis tree.

Results: This patient was diagnosed with SFTSV encephalitis, and the viral strain was successfully isolated. The SFTSV strain is closely related to the Hubei strain HB2017-02, and the SFTSV M and L fragments belong to the B genotype, whereas the M fragments belong to the F genotype. In addition, the similarities of coding sequences of case strain to those of tick-carried SFTSV strain in the residence were more than 99.9%.

Conclusions: The patient was confirmed to have SFTSV-infected encephalitis and died rapidly. The SFTSV strain was of Chinese local origin, and tick bites were the most likely route of infection.

References

Hayasaka D, Shimada S, Aoki K, Takamatsu Y, Uchida L, Horio M . Epidemiological Survey of Severe Fever with Thrombocytopenia Syndrome Virus in Ticks in Nagasaki, Japan. Trop Med Health. 2015; 43(3):159-64. PMC: 4593780. DOI: 10.2149/tmh.2015-01. View

Zohaib A, Zhang J, Saqib M, Athar M, Hussain M, Chen J . Serologic Evidence of Severe Fever with Thrombocytopenia Syndrome Virus and Related Viruses in Pakistan. Emerg Infect Dis. 2020; 26(7):1513-1516. PMC: 7323538. DOI: 10.3201/eid2607.190611. View

Cui N, Liu R, Lu Q, Wang L, Qin S, Yang Z . Severe fever with thrombocytopenia syndrome bunyavirus-related human encephalitis. J Infect. 2014; 70(1):52-9. DOI: 10.1016/j.jinf.2014.08.001. View

Rattanakomol P, Khongwichit S, Chuchaona W, Vongpunsawad S, Poovorawan Y . Severe fever with thrombocytopenia syndrome virus genotype B in Thailand. Arch Virol. 2023; 168(11):271. DOI: 10.1007/s00705-023-05897-1. View

Chen R, Li Q, Chen H, Yang H, Wei X, Chen M . Severe fever with thrombocytopenia syndrome virus replicates in brain tissues and damages neurons in newborn mice. BMC Microbiol. 2022; 22(1):204. PMC: 9392058. DOI: 10.1186/s12866-022-02609-8. View

Jiang X, Zhang S, Jiang M, Bi Z, Liang M, Ding S . A cluster of person-to-person transmission cases caused by SFTS virus in Penglai, China. Clin Microbiol Infect. 2015; 21(3):274-9. DOI: 10.1016/j.cmi.2014.10.006. View

Gundamraj V, Hasbun R . Viral meningitis and encephalitis: an update. Curr Opin Infect Dis. 2023; 36(3):177-185. DOI: 10.1097/QCO.0000000000000922. View

Wang C, Gong L, Zeng Z, Zhang J, Guan H, Chen L . Genome-based analysis of SFTSV causing severe encephalitis with brain lesions. J Neurovirol. 2019; 26(2):181-187. DOI: 10.1007/s13365-019-00816-0. View

Kim E, Park S . Emerging Tick-Borne : Virology, Epidemiology, and Prevention. Microorganisms. 2023; 11(9). PMC: 10536723. DOI: 10.3390/microorganisms11092309. View

10.

Silvas J, Aguilar P . The Emergence of Severe Fever with Thrombocytopenia Syndrome Virus. Am J Trop Med Hyg. 2017; 97(4):992-996. PMC: 5637595. DOI: 10.4269/ajtmh.16-0967. View

11.

Zheng H, Geng Y, Gu C, Li M, Mao M, Wan Y . A Reservoir Computing with Boosted Topology Model to Predict Encephalitis and Mortality for Patients with Severe Fever with Thrombocytopenia Syndrome: A Retrospective Multicenter Study. Infect Dis Ther. 2023; 12(5):1379-1391. PMC: 10156074. DOI: 10.1007/s40121-023-00808-y. View

12.

Kim D, Lai C, Cha I, Jung J . Current Progress of Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV) Vaccine Development. Viruses. 2024; 16(1). PMC: 10818334. DOI: 10.3390/v16010128. View

13.

Fu Y, Li S, Zhang Z, Man S, Li X, Zhang W . Phylogeographic analysis of severe fever with thrombocytopenia syndrome virus from Zhoushan Islands, China: implication for transmission across the ocean. Sci Rep. 2016; 6:19563. PMC: 4726339. DOI: 10.1038/srep19563. View

14.

Casel M, Park S, Choi Y . Severe fever with thrombocytopenia syndrome virus: emerging novel phlebovirus and their control strategy. Exp Mol Med. 2021; 53(5):713-722. PMC: 8178303. DOI: 10.1038/s12276-021-00610-1. View

15.

Yu X, Liang M, Zhang S, Liu Y, Li J, Sun Y . Fever with thrombocytopenia associated with a novel bunyavirus in China. N Engl J Med. 2011; 364(16):1523-32. PMC: 3113718. DOI: 10.1056/NEJMoa1010095. View

16.

Liu Q, He B, Huang S, Wei F, Zhu X . Severe fever with thrombocytopenia syndrome, an emerging tick-borne zoonosis. Lancet Infect Dis. 2014; 14(8):763-772. DOI: 10.1016/S1473-3099(14)70718-2. View

17.

Gai Z, Zhang Y, Liang M, Jin C, Zhang S, Zhu C . Clinical progress and risk factors for death in severe fever with thrombocytopenia syndrome patients. J Infect Dis. 2012; 206(7):1095-102. DOI: 10.1093/infdis/jis472. View

18.

Kobayashi Y, Kato H, Yamagishi T, Shimada T, Matsui T, Yoshikawa T . Severe Fever with Thrombocytopenia Syndrome, Japan, 2013-2017. Emerg Infect Dis. 2020; 26(4):692-699. PMC: 7101122. DOI: 10.3201/eid2604.191011. View

19.

Kuan C, Lin T, Ou S, Chuang S, Chan J, Maeda K . The First Nationwide Surveillance of Severe Fever with Thrombocytopenia Syndrome in Ruminants and Wildlife in Taiwan. Viruses. 2023; 15(2). PMC: 9965706. DOI: 10.3390/v15020441. View

20.

Li D . A highly pathogenic new bunyavirus emerged in China. Emerg Microbes Infect. 2015; 2(1):e1. PMC: 3630492. DOI: 10.1038/emi.2013.1. View