-
BMC Infectious Diseases Jan 2024Severe fever with thrombocytopenia syndrome (SFTS) is an emerging zoonosis with a high fatality rate in China. Previous studies have reported that dysregulated...
BACKGROUND
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging zoonosis with a high fatality rate in China. Previous studies have reported that dysregulated inflammatory response is associated with disease pathogenesis and mortality in patients with SFTS. This investigation aimed to evaluate the prevalence and characteristics of systemic inflammatory response syndrome (SIRS), and its impact on prognosis.
METHODS
Data on demographic characteristics, comorbid conditions, clinical manifestations, laboratory parameters, and survival time of patients with SFTS were collected. Patients were divided into the non-SIRS and SIRS groups according to the presence of SIRS, then their clinical data were compared.
RESULTS
A total of 290 patients diagnosed with SFTS were retrospectively enrolled, including 126(43.4%) patients with SIRS. Patients in the non-survivor group had more prevalence of SIRS than patients in the survivor group (P < 0.001), and SIRS (adjusted OR 2.885, 95% CI 1.226-6.786; P = 0.005) was shown as an independent risk factor for prognosis of patients with SFTS. Compared with patients without SIRS, patients with SIRS had lower WBC and neutrophils counts, and fibrinogen levels, but higher AST, LDH, amylase, lipase, CK, CK-MB, troponin I, APTT, thrombin time, D-dimer, CRP, IL-6, SAA levels, and viral load. The cumulative survival rate of patients with SIRS was significantly lower than that of patients without SIRS. Patients with SIRS also showed a higher incidence of bacterial or fungal infections than patients without SIRS.
CONCLUSIONS
SIRS is highly frequent in patients with SFTS, and it is associated with high mortality.
Topics: Humans; Severe Fever with Thrombocytopenia Syndrome; Retrospective Studies; Prevalence; Phlebovirus; Thrombocytopenia; Fever; Prognosis; Systemic Inflammatory Response Syndrome; China
PubMed: 38291390
DOI: 10.1186/s12879-024-09026-4 -
Virology Journal May 2024Rift Valley fever (RVF) is a zoonotic viral disease of increasing intensity among humans in Africa and the Arabian Peninsula. In Uganda, cases reported prior to 2016...
BACKGROUND
Rift Valley fever (RVF) is a zoonotic viral disease of increasing intensity among humans in Africa and the Arabian Peninsula. In Uganda, cases reported prior to 2016 were mild or not fully documented. We report in this paper on the severe morbidity and hospital-based mortality of human cases in Uganda.
METHODS
Between November 2017 and March 2020 human cases reported to the Uganda Virus Research Institute (UVRI) were confirmed by polymerase chain reaction (PCR). Ethical and regulatory approvals were obtained to enrol survivors into a one-year follow-up study. Data were collected on socio-demographics, medical history, laboratory tests, potential risk factors, and analysed using Stata software.
RESULTS
Overall, 40 cases were confirmed with acute RVF during this period. Cases were not geographically clustered and nearly all were male (39/40; 98%), median age 32 (range 11-63). The median definitive diagnosis time was 7 days and a delay of three days between presumptive and definitive diagnosis. Most patients (31/40; 78%) presented with fever and bleeding at case detection. Twenty-eight (70%) cases were hospitalised, out of whom 18 (64%) died. Mortality was highest among admissions in regional referral (11/16; 69%) and district (4/5; 80%) hospitals, hospitalized patients with bleeding at case detection (17/27; 63%), and patients older than 44 years (9/9; 100%). Survivors mostly manifested a mild gastro-intestinal syndrome with nausea (83%), anorexia (75%), vomiting (75%), abdominal pain (50%), and diarrhoea (42%), and prolonged symptoms of severe disease including jaundice (67%), visual difficulties (67%), epistaxis (50%), haemoptysis (42%), and dysentery (25%). Symptom duration varied between two to 120 days.
CONCLUSION
RVF is associated with high hospital-based mortality, severe and prolonged morbidity among humans that present to the health care system and are confirmed by PCR. One-health composite interventions should be developed to improve environmental and livestock surveillance, prevent infections, promptly detect outbreaks, and improve patient outcomes.
Topics: Humans; Uganda; Rift Valley Fever; Male; Adult; Middle Aged; Adolescent; Female; Young Adult; Child; Rift Valley fever virus; Hospital Mortality; Morbidity; Risk Factors
PubMed: 38702807
DOI: 10.1186/s12985-024-02377-z -
Medicina (Kaunas, Lithuania) Nov 2023: The Wakayama prefecture is endemic for two types of tick-borne rickettsioses: Japanese spotted fever (JFS) and scrub typhus (ST). Severe fever with thrombocytopenia...
: The Wakayama prefecture is endemic for two types of tick-borne rickettsioses: Japanese spotted fever (JFS) and scrub typhus (ST). Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne hemorrhagic viral disease with a high mortality rate and is often difficult to differentiate from such rickettsioses. SFTS cases have recently increased in Wakayama prefecture. For early diagnosis, this study aimed to evaluate the clinical characterization of such tick-borne infections in the co-endemic area. : The study included 64 febrile patients diagnosed with tick-borne infection in Wakayama prefecture between January 2013 and May 2022. Medical records of 19 patients with SFTS and 45 with rickettsiosis (JSF, = 26; ST, = 19) were retrospectively examined. The receiver operating curve (ROC) and area under the curve (AUC) were calculated to evaluate potential factors for differentiating SFTS from rickettsiosis. : Adults aged ≥70 years were most vulnerable to tick-borne infections (median, 75.5 years; interquartile range, 68.5-84 years). SFTS and rickettsiosis occurred mostly between summer and autumn. However, no significant between-group differences were found in age, sex, and comorbidities; 17 (89%) patients with SFTS, but none of those with rickettsiosis, experienced gastrointestinal symptoms such as vomiting, abdominal pain, and diarrhea. Meanwhile, 43 (96%) patients with rickettsiosis, but none of those with SFTS, developed a skin rash. The AUCs of white blood cells (0.97) and C-reactive protein (CRP) levels (0.98) were very high. Furthermore, the differential diagnosis of SFTS was significantly associated with the presence of gastrointestinal symptoms (AUC 0.95), the absence of a skin rash (AUC 0.98), leukopenia <3.7 × 10/L (AUC 0.95), and low CRP levels < 1.66 mg/dL (AUC 0.98) ( < 0.001 for each factor). : Clinical characteristics and standard laboratory parameters can verify the early diagnosis of SFTS in areas where tick-borne infections are endemic.
Topics: Adult; Humans; Severe Fever with Thrombocytopenia Syndrome; Phlebovirus; Retrospective Studies; Japan; Rickettsia Infections; Scrub Typhus; Tick-Borne Diseases; Exanthema
PubMed: 38004073
DOI: 10.3390/medicina59112024 -
Tropical Medicine and Infectious Disease Dec 2023In the Old World, phlebotomine sand flies from the genus are implicated in the transmission of spp. parasites (Kinetoplastida: Trypanosomatidae) and viruses belonging...
In the Old World, phlebotomine sand flies from the genus are implicated in the transmission of spp. parasites (Kinetoplastida: Trypanosomatidae) and viruses belonging to the genus (Bunyavirales: Phenuiviridae). Two of the five sand fly species known to occur in Portugal, and , the former being the most ubiquitous, are recognized vectors of , which causes visceral leishmaniasis, the most prevalent form of leishmaniasis in the country. is also the vector of the neurotropic Toscana virus, which can cause aseptic meningitis. Entomological surveillance is essential to provide fundamental data about the presence of vectors and the pathogens they can carry. As such, and given the lack of data in Portugal, an entomological survey took place in the Algarve, the southernmost region of the country, from May to October 2018. Polymerase chain reaction assays were performed in order to detect the presence of the above-mentioned pathogens in sand fly pools. Not only were both parasites and phleboviruses detected during this study, but more importantly, it was the first time their co-circulation was verified in the same sand fly population collected in Portugal.
PubMed: 38276633
DOI: 10.3390/tropicalmed9010003 -
Ticks and Tick-borne Diseases Mar 2024Severe fever with thrombocytopenia syndrome virus (SFTSV) is a bunyavirus that causes SFTS, with a case fatality rate of up to 30 %. The innate immune system plays a...
Severe fever with thrombocytopenia syndrome virus (SFTSV) is a bunyavirus that causes SFTS, with a case fatality rate of up to 30 %. The innate immune system plays a crucial role in the defense against SFTSV; however, the impact of viral propagation of STFSV on the innate immune system remains unclear. Although proteomics analysis revealed that the expression of the downregulator of transcription 1 (DR1) increased after SFTSV infection, the specific change trend and the functional role of DR1 during viral infection remain unelucidated. In this study, we demonstrate that DR1 was highly expressed in response to SFTSV infection in HEK 293T cells using qRT-PCR and Western blot analysis. Furthermore, viral replication significantly increased the expression of various TLRs, especially TLR9. Our data indicated that DR1 positively regulated the expression of TLRs in HEK 293T cells, DR1 overexpression highly increased the expression of numerous TLRs, whereas RNAi-mediated DR1 silencing decreased TLR expression. Additionally, the myeloid differentiation primary response gene 88 (MyD88)-dependent or TIR-domain-containing adaptor inducing interferon-β (TRIF)-dependent signaling pathways were highly up- and downregulated by the overexpression and silencing of DR1, respectively. Finally, we report that DR1 stimulates the expression of TLR7, TLR8, and TLR9, thereby upregulating the TRIF-dependent and MyD88-dependent signaling pathways during the SFTSV infection, attenuating viral replication, and enhancing the production of type I interferon and various inflammatory factors, including IL-1β, IL-6, and IL-8. These results imply that DR1 defends against SFTSV replication by inducing the expression of TLR7, TLR8, and TLR9. Collectively, our findings revealed a novel role and mechanism of DR1 in mediating antiviral responses and innate immunity.
Topics: Animals; Humans; Adaptor Proteins, Vesicular Transport; Down-Regulation; HEK293 Cells; Myeloid Differentiation Factor 88; Phosphoproteins; Signal Transduction; Toll-Like Receptor 7; Toll-Like Receptor 8; Toll-Like Receptor 9; Transcription Factors; Phlebovirus; Bunyaviridae Infections
PubMed: 38194758
DOI: 10.1016/j.ttbdis.2023.102307 -
Pathogens (Basel, Switzerland) Sep 2023Phlebotomine sand flies (Diptera: Psychodidae) are the principal vectors of phleboviruses and spp., the causative agents of leishmaniases. The Mediterranean sand fly...
Phlebotomine sand flies (Diptera: Psychodidae) are the principal vectors of phleboviruses and spp., the causative agents of leishmaniases. The Mediterranean sand fly fauna is diverse, and leishmaniasis, mainly caused by is endemic in the Balkan countries. Despite recent entomological surveys, only some districts of Kosovo have been sampled for sand flies, with no proof/confirmation of . This study aimed to gain further insights into the species composition of natural sand fly populations in previously unsampled districts and areas in Kosovo without reports of leishmaniasis and to detect DNA in sand flies. A sand fly survey was conducted in 2022 in all seven districts of Kosovo. Collected females were screened for DNA by PCR. Positive samples were sequenced and subjected to maximum likelihood analysis with reference sequences for further molecular characterization. The trapping activities at 114 different localities resulted in 3272 caught specimens, comprising seven sand fly species of two genera, namely , , , , , and . DNA was detected in three individual sand flies of and This study provides the most extensive sand fly survey in Kosovo and reports the first record of DNA in sand flies, indicating autochthonous circulation of .
PubMed: 37887706
DOI: 10.3390/pathogens12101190 -
Viruses Oct 2023Severe Fever with thrombocytopenia syndrome (SFTS) is a highly fatal viral infectious disease that poses a significant threat to public health. Currently, the phase and...
Severe Fever with thrombocytopenia syndrome (SFTS) is a highly fatal viral infectious disease that poses a significant threat to public health. Currently, the phase and pathogenesis of SFTS are not well understood, and there are no specific vaccines or effective treatment available. Therefore, it is crucial to identify biomarkers for diagnosing acute SFTS, which has a high mortality rate. In this study, we conducted differentially expressed genes (DEGs) analysis and WGCNA module analysis on the GSE144358 dataset, comparing the acute phase of SFTSV-infected patients with healthy individuals. Through the LASSO-Cox and random forest algorithms, a total of 2128 genes were analyzed, leading to the identification of four genes: ADIPOR1, CENPO, E2F2, and H2AC17. The GSEA analysis of these four genes demonstrated a significant correlation with immune cell function and cell cycle, aligning with the functional enrichment findings of DEGs. Furthermore, we also utilized CIBERSORT to analyze the immune cell infiltration and its correlation with characteristic genes. The results indicate that the combination of ADIPOR1, CENPO, E2F2, and H2AC17 genes has the potential as characteristic genes for diagnosing and studying the acute phase of SFTS virus (SFTSV) infection.
Topics: Humans; Severe Fever with Thrombocytopenia Syndrome; Bunyaviridae Infections; Phlebovirus; Cyclic N-Oxides; Ethylnitrosourea
PubMed: 37896902
DOI: 10.3390/v15102126 -
Virology Journal Sep 2023Severe fever with thrombocytopenia syndrome (SFTS) is an infectious disease caused by the Dabie bandavirus, [or SFTS virus (SFTSV)] that has become increasingly...
BACKGROUND
Severe fever with thrombocytopenia syndrome (SFTS) is an infectious disease caused by the Dabie bandavirus, [or SFTS virus (SFTSV)] that has become increasingly widespread since it was first reported in 2009. The SFTSV comprises three essential single-stranded RNA gene segments, with the S segment encoding the nucleocapsid (N) protein. Since the N protein is the most abundant and stable viral protein, it is a useful diagnostic marker of infection. Various SFTSV N-protein-based detection methods have been developed. However, given the limited research on antibodies of an SFTSV N-protein, here we report the characterization of the antibodies against SFTSV N protein especially their mapping results which is essential for more efficient and optimized detection of SFTSV.
METHODS
To generate SFTSV-N-protein-specific monoclonal antibodies, recombinant full-length SFTSV N protein was expressed in E. coli, and the purified N protein was immunized to mice. The binding epitope positions of the antibodies generated were identified through binding-domain mapping. An antibody pair test using a lateral flow immunoassay (LFIA) was performed to identify effective diagnostic combinations of paired antibodies.
RESULTS
Nine monoclonal antibodies specific for the SFTSV N protein were generated. Antibodies #3(B4E2) and #5(B4D9) were specific for sequential epitopes, while the remainder were specific for conformational epitopes. Antibody #4(C2G1) showed the highest affinity for the SFTSV N protein. The binding domain mapping results indicated the binding regions of the antibodies were divided into three groups. The antibody pair test demonstrated that #3(B4E2)/#4(C2G1) and #4(C2G1)/#5(B4D9) were effective antibody pairs for SFTSV diagnosis.
CONCLUSIONS
Effective virus detection requires at least two strong antibodies recognizing separate epitope binding sites of the virus antigen. Here, we generated SFTSV-N-protein-specific monoclonal antibodies and subsequently performed epitope mapping and an antibody pair test to enhance the diagnostic efficiency and accuracy of SFTSV. Confirmation of epitope mappings and their combination immune response to the N protein provide valuable information for effective detection of SFTSV as well as can respond actively to detect a variant SFTSV.
Topics: Animals; Mice; Antibody Formation; Nucleoproteins; Escherichia coli; Thrombocytopenia; Fever; Antibodies, Monoclonal; Epitopes
PubMed: 37679757
DOI: 10.1186/s12985-023-02173-1 -
BMC Infectious Diseases Dec 2023Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease discovered in China in 2009. The purpose of this study was to describe the...
BACKGROUND
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease discovered in China in 2009. The purpose of this study was to describe the spatiotemporal distribution of SFTS and to identify its environmental influencing factors and potential high-risk areas in Shandong Province, China.
METHODS
Data on the SFTS incidence from 2010 to 2021 were collected. Spatiotemporal scan statistics were used to identify the time and area of SFTS clustering. The maximum entropy (MaxEnt) model was used to analyse environmental influences and predict high-risk areas.
RESULTS
From 2010 to 2021, a total of 5705 cases of SFTS were reported in Shandong. The number of SFTS cases increased yearly, with a peak incidence from April to October each year. Spatiotemporal scan statistics showed the existence of one most likely cluster and two secondary likely clusters in Shandong. The most likely cluster was in the eastern region, from May to October 2021. The first secondary cluster was in the central region, from May to October 2021. The second secondary cluster was in the southeastern region, from May to September 2020. The MaxEnt model showed that the mean annual wind speed, NDVI, cattle density and annual cumulative precipitation were the key factors influencing the occurrence of SFTS. The predicted risk map showed that the area of high prevalence was 28,120 km, accounting for 18.05% of the total area of the province.
CONCLUSIONS
The spatiotemporal distribution of SFTS was heterogeneous and influenced by multidimensional environmental factors. This should be considered as a basis for delineating SFTS risk areas and developing SFTS prevention and control measures.
Topics: Animals; Cattle; Severe Fever with Thrombocytopenia Syndrome; Phlebovirus; Thrombocytopenia; Incidence; China
PubMed: 38124061
DOI: 10.1186/s12879-023-08899-1 -
BMC Veterinary Research May 2024Severe fever with thrombocytopenia syndrome (SFTS) is a fatal zoonosis caused by ticks in East Asia. As SFTS virus (SFTSV) is maintained between wildlife and ticks,...
Severe fever with thrombocytopenia syndrome (SFTS) is a fatal zoonosis caused by ticks in East Asia. As SFTS virus (SFTSV) is maintained between wildlife and ticks, seroepidemiological studies in wildlife are important to understand the behavior of SFTSV in the environment. Miyazaki Prefecture, Japan, is an SFTS-endemic area, and approximately 100 feral horses, called Misaki horses (Equus caballus), inhabit Cape Toi in Miyazaki Prefecture. While these animals are managed in a wild-like manner, their ages are ascertainable due to individual identification. In the present study, we conducted a seroepidemiological survey of SFTSV in Misaki horses between 2015 and 2023. This study aimed to understand SFTSV infection in horses and its transmission to wildlife. A total of 707 samples from 180 feral horses were used to determine the seroprevalence of SFTSV using enzyme-linked immunosorbent assay (ELISA). Neutralization testing was performed on 118 samples. In addition, SFTS viral RNA was detected in ticks from Cape Toi and feral horses. The overall seroprevalence between 2015 and 2023 was 78.5% (555/707). The lowest seroprevalence was 55% (44/80) in 2016 and the highest was 92% (76/83) in 2018. Seroprevalence was significantly affected by age, with 11% (8/71) in those less than one year of age and 96.7% (435/450) in those four years of age and older (p < 0.0001). The concordance between ELISA and neutralization test results was 88.9% (105/118). SFTS viral RNA was not detected in ticks (n = 516) or feral horses. This study demonstrated that horses can be infected with SFTSV and that age is a significant factor in seroprevalence in wildlife. This study provides insights into SFTSV infection not only in horses but also in wildlife in SFTS-endemic areas.
Topics: Animals; Horses; Seroepidemiologic Studies; Japan; Horse Diseases; Phlebovirus; Severe Fever with Thrombocytopenia Syndrome; Female; Male; Antibodies, Viral; Ticks; Enzyme-Linked Immunosorbent Assay; Animals, Wild
PubMed: 38734647
DOI: 10.1186/s12917-024-04042-7