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Vector Borne and Zoonotic Diseases... Dec 2023Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by , which belongs to the genus , family , and order Bunyavirales. It has...
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by , which belongs to the genus , family , and order Bunyavirales. It has been found in tick species, various animals, and humans. The aim of this study was to detect RNA of antigens and antibodies against SFTS virus (SFTSV) among poultry such as chickens, ducks, and wild geese from five provinces in the Republic of Korea (ROK). A one-step reverse transcriptase (RT)-PCR and nested PCR were performed after viral RNA extraction. The phylogenetic tree was constructed after sequencing data were analyzed and aligned. An indirect enzyme-linked immunosorbent assay (ELISA) and a neutralization test (NT) were performed to test for IgG antibodies of SFTSV. Of a total of 606 poultry serum samples collected, 568 and 539 serum samples were used to perform ELISA and NT, respectively. Of a total of 606 serum samples tested by RT-PCR targeting the S segment, 15 (2.5%) were positive for SFTSV. From the 15 positive serum samples for the SFTSV antigen, three from chickens, three from ducks, and one from wild geese were classified as genotype B-2; one from chickens was classified as genotype B-3; and three from chickens and four from wild geese were classified as genotype D. Of the 568 serum samples tested by ELISA, 83 (28.0%) from chickens, 81 (32.9%) from ducks, and 8 (30.8%) from wild geese were seropositive. Of the 539 serum samples for which an NT was performed, 113 (38.6%) from chickens and 75 (30.5%) from ducks were positive for SFTSV antibodies. The results of this study provide useful information regarding detection of SFTSV RNA and antibodies among poultry and the possibility of SFTSV transmission in various types of poultry, including chickens, ducks, and wild geese, in the ROK.
Topics: Humans; Animals; Severe Fever with Thrombocytopenia Syndrome; Poultry; Prevalence; Phylogeny; Bunyaviridae Infections; Chickens; Phlebovirus; Ducks; RNA, Viral; Republic of Korea
PubMed: 37788402
DOI: 10.1089/vbz.2023.0028 -
Nucleic Acids Research Feb 2023Severe fever with thrombocytopenia syndrome virus (SFTSV) is a phenuivirus that has rapidly become endemic in several East Asian countries. The large (L) protein of...
Severe fever with thrombocytopenia syndrome virus (SFTSV) is a phenuivirus that has rapidly become endemic in several East Asian countries. The large (L) protein of SFTSV, which includes the RNA-dependent RNA polymerase (RdRp), is responsible for catalysing viral genome replication and transcription. Here, we present 5 cryo-electron microscopy (cryo-EM) structures of the L protein in several states of the genome replication process, from pre-initiation to late-stage elongation, at a resolution of up to 2.6 Å. We identify how the L protein binds the 5' viral RNA in a hook-like conformation and show how the distal 5' and 3' RNA ends form a duplex positioning the 3' RNA terminus in the RdRp active site ready for initiation. We also observe the L protein stalled in the early and late stages of elongation with the RdRp core accommodating a 10-bp product-template duplex. This duplex ultimately splits with the template binding to a designated 3' secondary binding site. The structural data and observations are complemented by in vitro biochemical and cell-based mini-replicon assays. Altogether, our data provide novel key insights into the mechanism of viral genome replication by the SFTSV L protein and will aid drug development against segmented negative-strand RNA viruses.
Topics: Humans; Severe Fever with Thrombocytopenia Syndrome; Cryoelectron Microscopy; RNA, Viral; RNA-Dependent RNA Polymerase; Phlebovirus; Virus Replication; Genome, Viral
PubMed: 36651274
DOI: 10.1093/nar/gkac1249 -
Protein & Cell Dec 2023
Topics: Humans; Severe Fever with Thrombocytopenia Syndrome; Phlebovirus
PubMed: 37038326
DOI: 10.1093/procel/pwad019 -
Emerging Infectious Diseases Oct 2020We isolated 17 viral strains capable of causing cytopathic effects in mammalian cells and death in neonatal mice from sand flies in China. Phylogenetic analysis showed...
We isolated 17 viral strains capable of causing cytopathic effects in mammalian cells and death in neonatal mice from sand flies in China. Phylogenetic analysis showed that these strains belonged to the genus Phlebovirus. These findings highlight the need to control this potentially emerging virus to help safeguard public health.
Topics: Animals; China; Mice; Phlebovirus; Phylogeny; Psychodidae
PubMed: 32946723
DOI: 10.3201/eid2610.191374 -
Journal of Medical Virology Apr 2023Co-infection in patients with severe fever with thrombocytopenia syndrome (SFTS) has been reported, posing a serious threat to survival and treatment. We aimed to... (Observational Study)
Observational Study
Co-infection in patients with severe fever with thrombocytopenia syndrome (SFTS) has been reported, posing a serious threat to survival and treatment. We aimed to systematically investigate the SFTS associated pulmonary infection, particularly invasive pulmonary fungal infection (IPFI). During April 2019 to October 2021, we conducted a multicentre observational study on adult hospitalized patients confirmed with SFTS from three tertiary hospital in central China. Demographic, clinical and laboratory data of patients were collected and re-assessed. A total of 443 patients (51.7% were male sex) were included for analysis with median age of 65-year-old. Among them, 190 (42.9%) patients met the criteria for pulmonary infection. Pulmonary infection was associated with shorter survival time (p < 0.0001 by log-rank test), and adjusted hazard ratio was 1.729 [95% confidence interval, 1.076-2.780] (p = 0.024). Age (odds ratio (OR) 1.040 [1.019-1.062], p < 0.001), time from onset to admission (OR 1.163 [1.070-1.264], p < 0.001), having severe status (OR 3.166 [2.020-4.962], p < 0.001) and symptoms of skin change (OR 2.361 [1.049-5.316], p < 0.001) at admission and receiving intravenous immunoglobin (OR 2.185 [1.337-3.569], p = 0.002) were independent risk factors for the occurrence of pulmonary infection. A total of 70 (15.8%) patients were defined as IPFI. Multivariate analysis showed that time from onset to admission (OR 1.117 [1.016-1.229], p = 0.022), severe status (OR 5.737 [3.054-10.779], p < 0.001), having smoking history (OR 3.178 [1.251-8.070], p = 0.015) and autoimmunity disease (OR 7.855 [1.632-37.796], p = 0.010), receiving intravenous immunoglobin (OR 3.270 [1.424-7.508], p = 0.005) were independent risk factors for the occurrence of IPFI. In SFTS patients with pulmonary infection, white blood count <2.09 × 10 per L (OR 11.064 [3.708-33.012], p < 0.001) and CD3 CD4 T cell count <104.0 per μL (OR 10.429 [3.395-32.038], p < 0.001) could independently predict IPFI. This study showed the high prevalence and poor outcomes of pulmonary infection and IPFI in patients with SFTS. These findings highlighted the need for active surveillance of fungal pathogens and early antifungal treatment in patients with SFTS.
Topics: Adult; Humans; Male; Aged; Female; Severe Fever with Thrombocytopenia Syndrome; Phlebovirus; Thrombocytopenia; Lung; Pneumonia
PubMed: 36991571
DOI: 10.1002/jmv.28712 -
Viruses Sep 2022Viral coinfections can modulate the severity of parasitic diseases, such as human cutaneous leishmaniasis. Leishmania parasites infect thousands of people worldwide and...
Viral coinfections can modulate the severity of parasitic diseases, such as human cutaneous leishmaniasis. Leishmania parasites infect thousands of people worldwide and cause from single cutaneous self-healing lesions to massive mucosal destructive lesions. The transmission to vertebrates requires the bite of Phlebotomine sandflies, which can also transmit Phlebovirus. We have demonstrated that Leishmania infection requires and triggers the Endoplasmic stress (ER stress) response in infected macrophages. In the present paper, we tested the hypothesis that ER stress is increased and required for the aggravation of infection due to coinfection with . We demonstrated that Icoaraci induces the ER stress program in macrophages mediated by the branches IRE/XBP1 and PERK/ATF4. The coinfection with potentiates and sustains the ER stress, and the inhibition of IRE1α or PERK results in poor viral replication and decreased parasite load in macrophages. Importantly, we observed an increase in viral replication during the coinfection with . Our results demonstrated the role of ER stress branches IRE1/XBP1 and PERK/ATF4 in the synergic effect on the Leishmania increased load during coinfection and suggests that infection can also increase the replication of in macrophages.
Topics: Animals; Coinfection; Endoribonucleases; Humans; Leishmania; Leishmaniasis; Orthobunyavirus; Phlebovirus; Protein Serine-Threonine Kinases
PubMed: 36146755
DOI: 10.3390/v14091948 -
Clinical Immunology (Orlando, Fla.) Mar 2023This study aimed to make a comprehensive evaluation of peripheral immune profiles for further understanding the immunopathogenesis of severe fever with thrombocytopenia...
OBJECTIVE
This study aimed to make a comprehensive evaluation of peripheral immune profiles for further understanding the immunopathogenesis of severe fever with thrombocytopenia syndrome (SFTS).
METHODS
Forty-seven patients with SFTS virus infection were included, of which 24 were deceased. The percentages, absolute numbers, phenotype of lymphocyte subsets were detected by flow cytometry.
RESULTS
In patients with SFTS, the numbers of CD3T, CD4T, CD8T and NKT cells were decreased compared with healthy controls (HCs), accompanied with highly active and exhausted phenotypes for T cells, and overproliferating plasmablasts. High inflammatory status, dysregulation of coagulation and host immune response were more obvious in deceased patients than that of survivors. Higher levels of PCT, IL-6, IL-10, TNF-α, APTT, TT and the occurrence of hemophagocytic lymphohistiocytosis were poor prognostic indicators of SFTS.
CONCLUSIONS
The evaluation of immunological markers in combination with laboratory tests has critical value for selecting prognostic markers and potential treatment target.
Topics: Humans; Severe Fever with Thrombocytopenia Syndrome; Thrombocytopenia; Phlebovirus; Lymphocyte Subsets; Prognosis
PubMed: 36796470
DOI: 10.1016/j.clim.2023.109262 -
Frontiers in Immunology 2024Dabie Banda virus (DBV), a tick-borne pathogen, was first identified in China in 2009 and causes profound symptoms including fever, leukopenia, thrombocytopenia and... (Review)
Review
Dabie Banda virus (DBV), a tick-borne pathogen, was first identified in China in 2009 and causes profound symptoms including fever, leukopenia, thrombocytopenia and multi-organ dysfunction, which is known as severe fever with thrombocytopenia syndrome (SFTS). In the last decade, global incidence and mortality of SFTS increased significantly, especially in East Asia. Though previous studies provide understandings of clinical and immunological characteristics of SFTS development, comprehensive insight of antiviral immunity response is still lacking. Here, we intensively discuss the antiviral immune response after DBV infection by integrating previous ex- and in-vivo studies, including innate and adaptive immune responses, anti-viral immune responses and long-term immune characters. A comprehensive overview of potential immune targets for clinical trials is provided as well. However, development of novel strategies for improving the prognosis of the disease remains on challenge. The current review may shed light on the establishment of immunological interventions for the critical disease SFTS.
Topics: Animals; Humans; Adaptive Immunity; Immunity, Innate; Phlebovirus; Severe Fever with Thrombocytopenia Syndrome
PubMed: 38646523
DOI: 10.3389/fimmu.2024.1348836 -
Deutsches Arzteblatt International Aug 2022
Topics: Humans; Sandfly fever Naples virus; Meningoencephalitis; Immunoglobulin M
PubMed: 36384926
DOI: 10.3238/arztebl.m2022.0224 -
PLoS Neglected Tropical Diseases Nov 2023The increased pancreatic enzymes have recently been reported in patients with severe fever with thrombocytopenia syndrome (SFTS). However, its significance has not been...
BACKGROUND AND AIM
The increased pancreatic enzymes have recently been reported in patients with severe fever with thrombocytopenia syndrome (SFTS). However, its significance has not been elucidated clearly. The aim of this study was to explore the prevalence, clinical characteristics of elevated pancreatic enzymes (amylase and lipase) and its association with AP in patients with SFTS.
METHODS
Data of demographics, comorbid conditions, clinical symptoms, laboratory parameters and survival time of patients with SFTS were collected. Patients were assigned into the non-AP and AP groups according to the diagnostic criteria of AP. Patients in the non-AP group were divided into the normal (
3×ULN) groups according to the serum amylase and lipase levels, and then their clinical data were compared. RESULTS
A total of 284 patients diagnosed with SFTS were retrospectively enrolled, including 248 patients in the non-AP group and 36 patients in the AP group. Patients in the non-AP group were composed of 48, 116 and 84 patients in the normal, EPE and HPE groups, respectively. Compared with patients in the normal and EPE groups, patients in the HPE group had higher serum levels of laboratory parameters referring to liver, kidney, heart and coagulation system injury, as well as higher viral load. The cumulative survival rate of patients in the HPE group was significantly lower than that of patients in the normal group. In addition, patients in the AP group also had higher serum levels of laboratory variables reflecting liver, heart, coagulation dysfunction and viral load than patients in the HPE group. The cumulative survival rate of patients in the AP group was significantly lower than that of patients in the HPE group.
CONCLUSION
The increased pancreatic enzymes are very common in patients with SFTS, but they are not always associated with AP. Though AP accounts for the majority of deaths for patients with elevated pancreatic enzymes, patients with pancreatic enzymes >3×ULN except for AP also have a high in-hospital mortality rate.
Topics: Humans; Severe Fever with Thrombocytopenia Syndrome; Retrospective Studies; Prevalence; Phlebovirus; Lipase; Amylases
PubMed: 37943950
DOI: 10.1371/journal.pntd.0011758