Humans ; Severe Fever with Thrombocytopenia Syndrome ; Phlebovirus

Despite a high mortality rate, no specific treatment for severe fever with thrombocytopenia syndrome (SFTS) has been established. This study compared the clinical outcomes of SFTS patients treated with plasma exchange (PE group) with those who were not treated (non-PE group) at nine Korean hospitals between May 2013 and August 2015. A total of 53 SFTS patients were included: 24 (45.3%) PE cases and 29 (54.7%) non-PE cases. The overall in-hospital mortality rate was 32.1% (17/53). The in-hospital mortality rate of the PE group did not differ from that of the non-PE group (29.3% vs. 34.5%, p=0.680). Of the 24 PE cases, 16 (66.7%) were treated with PE within 7 days of symptom onset (early PE group). The early PE group survived longer than the non-PE group (mean 28.4 days vs. 22.6 days, p=0.044). Multivariate analysis showed an inverse association between early PE implementation and 30-day mortality (adjusted hazard ratio 0.052, 95% confidence interval 0.004–0.678, p=0.024). The results of this study suggest that early PE implementation may have a beneficial effect on the clinical outcome of SFTS patients.
Fever* ; Hospital Mortality ; Humans ; Mortality ; Multivariate Analysis ; Phlebovirus ; Plasma Exchange* ; Plasma* ; Thrombocytopenia*

Genus Phlebovirus is single negative-strand RNA virus, and belongs to family bunyaviridae. Its genomes have three segments including L, M and S encoding RNA-dependent RNA polymerase, envelope glycoprotein and nucleoprotein respectively. Phlebovirus is arbovirus and can be disseminated by arthropod. More than 70 types of Phlebovirus so far have been reported, and 68 known serotypes are divided into groups Sandfly fever and Uukuniemi, of which a few members are closely related to human diseases. In addition, new emerging viruses of genus Phlebovirus are discovered recently. In this review, the latest research progress in molecular characteristics, epidemiology, diagnosis, treatment and emerging viruses of Phlebovirus is summarized.
Animals ; Humans ; Phlebotomus Fever ; diagnosis ; epidemiology ; therapy ; virology ; Phlebovirus ; classification ; genetics ; isolation & purification ; physiology

OBJECTIVETo investigate the predominance ticks and the infectious status of severe fever with thrombocytopenia (SFTSV) in Penglai and Laizhou counties, Shandong province.

METHODSTwo towns with high incidence rate were selected in Penglai and Laizhou, respectively, then three villages were selected in each towns. Parasitic ticks were collected from the host skin by hand manually and free ticks manually with white cloth from the grassland, monthly, during April to December in 2011. Samples were classified by original, varieties, developmental stages, then extracted RNA, using Realtime RT-PCR to test severe fever thrombocytopenia syndrome virus, S fragments were amplified with nested PCR, then isolated virus. By neighbor joining method in the phylogenetic tree, the minimum infection rate (MIR) was used to represent the infection status of ticks in novel bunyavirus.

RESULTSA total of 3 145 ticks were collected totally from 5 categories, there were 3 048(96.92%) of Haemaphysalis longicornis, 73(2.32%) of Rhinpicephalus sanguineus, 10(0.32%) of microplus Boophilus, 9(0.29%) of Haemaphysalis campanulata, 5(0.16%) of Dermacentor sinicus, respectively. The positive rate of nucleic acid of 2 044 samples was 6.16% (126/2 044), minimum infection rate (MIR) was 4.01%, there were 122(96.83%) of Haemaphysalis longicornis, 3(2.38%) of Rhinpicephalus sanguineus, and 1(0.79%) of microplus Boophilus, MIR was 4.00%, 4.11%, and 10.00%, respectively. There were no nucleic acid positive samples in Haemaphysalis campanulata and Dermacentor sinicus. The 11 S segments were amplified in 126 positive samples, the homology of S fragment was 95.6%-99.9% with 11 strains isolated from the identified SFTS cases in local area, 3 strains isolated from animals, and 11 strains isolated from other areas. There was no significant difference among original, varieties and developmental stages.

CONCLUSIONHaemaphysalis longicornis was the predominant species in Penglai and Laizhou counties, it could be propagation medium with Rhipicephalus sanguineus and microplus Boophilus, S sequence in ticks was higher homology with virus isolated from local SFTS cases.

The incidence of severe fever with thrombocytopenia syndrome (SFTS) has increased in Korea since a first report in 2013. We investigated whether SFTS existed before 2013 using real-time reverse transcription polymerase chain reaction and stored blood samples from febrile patients with thrombocytopenia. Four cases of SFTS were identified, with the earliest occurring in 2008.
Fever* ; Humans ; Incidence ; Korea* ; Lymphohistiocytosis, Hemophagocytic* ; Phlebovirus ; Polymerase Chain Reaction ; Retrospective Studies* ; Reverse Transcription ; Thrombocytopenia*

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease caused by the newly discovered SFTS Bunyavirus, and there have been no case reports of SFTS patients presenting with hemophagocytic lymphohistiocytosis (HLH) in the English literature. We report a case of SFTS presenting with HLH in a 73-year-old immunocompetent male farmer. Although the patient had poor prognostic factors for SFTS, such as old age and central nervous system symptoms, he recovered fully with supportive care.
Aged ; Central Nervous System ; Farmers ; Fever* ; Humans ; Lymphohistiocytosis, Hemophagocytic* ; Male ; Orthobunyavirus ; Phlebovirus ; Thrombocytopenia* ; Tick-Borne Diseases

Animals ; Biological Assay ; Nucleic Acid Amplification Techniques ; Phlebovirus/isolation & purification* ; Psychodidae/virology* ; Recombinases/metabolism* ; Reverse Transcription

No abstract available.
Animals ; Humans ; Insect Bites and Stings/virology ; Phlebotomus Fever/*etiology/prevention & control/transmission ; Phlebovirus/isolation & purification/physiology ; Ticks/*virology

Severe fever with thrombocytopenia syndrome bunyavirus is a newly emerging virus in China, enveloped with a tripartite, single-stranded RNA genome of negative polarity. The regulatory elements for viral transcription and replication, as well as encapsidation and packaging signals, are thought to be located within these noncoding regions (NCRs). The terminal nucleotides are genus specific and highly conserved. The function of the remaining nucleotides of the NCRs is still not well understood. In this study, we developed the plasmid-driven RNA polymerase I minireplicon system for SFTSV firstly, using reporter genes GFP and luciferase. The function of the noncoding regions of the three Bunyaviridae RNA segments (L, M, S) in transcription was analyzed. Reporter genes are successfully expressed in SFTSV minireplicon system. Our results suggest that the NCRs of SFTSV from all three segments contain the necessary signals to initiate transcription. Quantitative detection of the luciferase expression level shows that promoter activity in the three segments is different.
Bunyaviridae Infections ; virology ; Cloning, Molecular ; Genome, Viral ; Humans ; Phlebovirus ; genetics ; physiology ; Replicon ; Viral Proteins ; genetics ; metabolism ; Virus Replication

OBJECTIVETo sequence the whole genome and to analyze the molecular and evolutionary of Severe fever with thrombocytopenia syndrome bunyavirus (SFTSV) isolated from Zhejiang province.

METHODSViral RNA was extracted from the specimens and detected by quantitative real-time RT-PCR. SFTSV strain was isolated. A total of 17 overlapping fragments covering the whole genome were amplified by RT-PCR. And the entire genomes were formed by sequencing and assembly the fragments. The SFTSV sequence of Zhejiang strain was compared with the sequences of SFTSV that have been published to generate the phylogenetic tree. And the SFTSV sequence of Zhejiang strain was compared with the sequences of strains of the genus phlebovirus in the Bunyaviridae family and analysis of homology.

RESULTSSFTSV strain was isolated from SFTSV infection positive serum successfully. The genomic fragments were amplified by RT-PCR. A total of 3 cDNA sections were formed by sequencing and assembly the fragments. The S segment contained 1 745 nucleotides. The M fragment contained 3 378 nucleotides, and the L segment contained 6 368 nucleotides. Molecular phylogenetic analysis result showed SFTSV Zhejiang strain had the highest similarity with Japan/SPL004A/2013 strain. The similarity of the S segment was 98%. The similarity of the M fragment was 97%. And it was 98% that of the L fragment. Meanwhile, the comparison results also confirmed the Zhejiang strain belonged to the genus phlebovirus.

CONCLUSIONSFTSV Zhejiang strain of isolated from SFTSV infection positive serum successfully. And the genome sequencing was complete molecular evolution analysis shows SFTSV Zhejiang strain has the maximum similarity with SFTSV Japan strain.