Severe Fever with Thrombocytopenia Syndrome, Japan, 2013-2017.
Kobayashi Yusuke,Kato Hirofumi,Yamagishi Takuya,Shimada Tomoe,Matsui Tamano,Yoshikawa Tomoki,Kurosu Takeshi,Shimojima Masayuki,Morikawa Shigeru,Hasegawa Hideki,Saijo Masayuki,Oishi Kazunori,
Emerging infectious diseases
We conducted an epidemiologic study of severe fever with thrombocytopenia syndrome (SFTS) in Japan during 2013-2017. Of 303 cases reported during that period, 133 (44%) were included in this study. The median time between onset of illness and diagnosis of SFTS shortened, from 11.5 to 3.0 days, but the case-fatality rate remained high, at 27%. In 64 patients (48%), a close contact with companion animals was reported within 2 weeks of disease onset. Of these 64 patients, 40 were surveyed further, and we confirmed that 3 had direct contact with body fluids of ill companion animals; 2 had direct contact with the saliva of an ill feral cat or pet dog. These patients reported no history of tick bite, suggesting that ill companion animals might be a source of SFTS virus transmission. Direct contact with the body fluids of ill companion animals should be avoided.
10.3201/eid2604.191011
A scoring model for predicting prognosis of patients with severe fever with thrombocytopenia syndrome.
Jia Bei,Yan Xiaomin,Chen Yuxin,Wang Guiyang,Liu Yong,Xu Biyun,Song Peixin,Li Yang,Xiong Yali,Wu Weihua,Hao Yingying,Xia Juan,Zhang Zhaoping,Huang Rui,Wu Chao
PLoS neglected tropical diseases
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging epidemic infectious disease caused by the SFTS bunyavirus (SFTSV) with an estimated high case-fatality rate of 12.7% to 32.6%. Currently, the disease has been reported in mainland China, Japan, Korea, and the United States. At present, there is no specific antiviral therapy for SFTSV infection. Considering the higher mortality rate and rapid clinical progress of SFTS, supporting the appropriate treatment in time to SFTS patients is critical. Therefore, it is very important for clinicians to predict these SFTS cases who are more likely to have a poor prognosis or even more likely to decease. In the present study, we established a simple and feasible model for assessing the severity and predicting the prognosis of SFTS patients with high sensitivity and specificity. This model may aid the physicians to immediately initiate prompt treatment to block the rapid development of the illness and reduce the fatality of SFTS patients.
10.1371/journal.pntd.0005909
The Differential Characteristics Between Severe Fever With Thrombocytopenia Syndrome and Hemorrhagic Fever With Renal Syndrome in the Endemic Regions.
Lu Qing-Bin,Li Hao,Jiang Fa-Chun,Mao Ling-Ling,Liu Xue-Sheng,Wang Ning,Zhou Yong-Yun,Dai Ke,Yang Zhen-Dong,Dong Li-Yan,Cui Ning,Zhang Xiao-Ai,Zhang Shao-Fei,Zhang Pan-He,Fang Li-Qun,Liu Wei
Open forum infectious diseases
An effective differentiation between severe fever with thrombocytopenia syndrome and hemorrhagic fever with renal syndrome was attained by a model considering patients' age, mouse/tick contact, presence of blush, low back pain, diarrhea, enlarged lymph nodes, and white blood cell count.
10.1093/ofid/ofz477
Persistence and gender differences in protection against severe fever with thrombocytopaenia syndrome virus with natural infection: a 4-year follow-up and mathematical prediction study.
Qi R,Huang Y T,Yu X J
Epidemiology and infection
Severe fever with thrombocytopaenia syndrome (SFTS) is an emerging infectious disease discovered in 2010 and has a case fatality as high as 30%. We intended to study the immune protection conferred by SFTS with natural infection. We collected and analysed 4-year follow-up data to study the characteristics of neutralising antibodies against SFTS virus (SFTSV). The 50% plaque reduction neutralisation test was used for the detection of neutralising antibodies against SFTSV. Geometric mean titres (GMTs) and proportions of patients with a protective titre were analysed, and the persistence of protection was predicted. The titre of antibodies declined yearly in the 4-year study period. Approximately 3 months after infection, the GMT was 143 (95% confidence interval (CI): 89-231), and 100% of patients had a protective titre. In the fourth year, the GMT declined to 53 (95% CI: 37-76), and 95% of patients had a protective titre. The titre was higher in females than in males. On average, the protection offered by neutralising antibodies against SFTSV could last as long as 9 years. The durations of protection were different for different initial titres. The characteristics of neutralising antibodies can be used as a reference for the vaccination doses and schedules of forthcoming vaccines.
10.1017/S1469440918003643
Clinical Score System to Differentiate Severe Fever with Thrombocytopenia Syndrome Patients from Patients with Scrub Typhus or Hemorrhagic Fever with Renal Syndrome in Korea.
Heo Dae Hyuk,Kang Yu Min,Song Kyoung Ho,Seo Jun Won,Kim Jeong Han,Chun June Young,Jun Kang Il,Kang Chang Kyung,Moon Song Mi,Choe Pyoeng Gyun,Park Wan Beom,Bang Ji Hwan,Kim Eu Suk,Kim Hong Bin,Park Sang Won,Oh Won Sup,Kim Nam Joong,Oh Myoung Don
Journal of Korean medical science
BACKGROUND:Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with high mortality in East Asia. This study aimed to develop, for primary care providers, a prediction score using initial symptoms and basic laboratory blood tests to differentiate between SFTS and other endemic zoonoses in Korea. METHODS:Patients aged ≥ 18 years diagnosed with endemic zoonoses during a 3-year period (between January 2015 and December 2017) were retrospectively enrolled from 4 tertiary university hospitals. A prediction score was built based on multivariate logistic regression analyses. RESULTS:Of 84 patients, 35 with SFTS and 49 with other endemic zoonoses were enrolled. In multivariate logistic regression analysis, independent predictors of SFTS included neurologic symptoms (odds ratio [OR], 12.915; 95% confidence interval [CI], 2.173-76.747), diarrhea (OR, 10.306; 95% CI, 1.588-66.895), leukopenia (< 4,000/mm³) (OR, 19.400; 95% CI, 3.290-114.408), and normal C-reactive protein (< 0.5 mg/dL) (OR, 24.739; 95% CI, 1.812-337.742). We set up a prediction score by assigning one point to each of these four predictors. A score of ≥ 2 had 82.9% sensitivity (95% CI, 71.7%-87.5%) and 95.9% specificity (95% CI, 88.0%-99.2%). The area under the curve of the clinical prediction score was 0.950 (95% CI, 0.903-0.997). CONCLUSION:This study finding suggests a simple and useful scoring system to predict SFTS in patients with endemic zoonoses. We expect this strategic approach to facilitate early differentiation of SFTS from other endemic zoonoses, especially by primary care providers, and to improve the clinical outcomes.
10.3346/jkms.2020.35.e77
Severe fever with thrombocytopenia syndrome: comparison with scrub typhus and clinical diagnostic prediction.
Park Sang-Won,Lee Chang-Seop,Kim Jeong-Han,Bae In-Gyu,Moon Chisook,Kwak Yee Gyung,Kim Baek-Nam,Lee Jae Hoon,Ryu Seong Yeol,Jang Hee-Chang,Hur Jian,Jun Jae-Bum,Jung Younghee,Chang Hyun-Ha,Kim Young Keun,Hwang Jeong-Hwan,Kim Yeon-Sook,Jeong Hye Won,Song Kyoung-Ho,Park Wan Beom,Kim Eu Suk,Oh Myoung-Don
BMC infectious diseases
BACKGROUND:Severe fever with thrombocytopenia syndrome (SFTS) is emerging in Asian 3 countries, China, Japan and Korea, which are scrub typhus endemic areas, and its incidence is increasing. As the two infections overlap epidemiologically and clinically and the accessibility or sensitivity of diagnostic tests is limited, early clinical prediction may be useful for diagnostic and therapeutic purposes. METHODS:Patients aged ≥16 years who were clinically suspected and laboratory-confirmed to be infected with Orientia tsutsugamushi or the SFTS virus in South Korea were enrolled. Clinical and laboratory parameters were compared. Scrub typhus was further subclassified according to the status of eschar and skin rash. An SFTS prediction scoring tool was generated based on a logistic regression analysis of SFTS compared with scrub typhus. RESULTS:The analysis was performed on 255 patients with scrub typhus and 107 patients with SFTS. At initial presentation, subjective symptoms except for gastrointestinal symptoms, were more prominent in scrub typhus patients. In addition to the characteristic eschar and skin rash, headache was significantly more prominent in scrub typhus, while laboratory abnormalities were more prominent in SFTS. Leukopenia (white blood cell count < 4000/mm; odds ratio [OR] 30.13), thrombocytopenia (platelet count < 80,000 /mm; OR 19.73) and low C-reactive protein (< 1 mg/dL; OR 67.46) were consistent risk factors for SFTS (all P < 0.001). A prediction score was generated using these 3 variables, and a score ≥ 2 had a sensitivity of 93.1% (95% confidence interval [CI], 87.9-96.4%) and a specificity of 96.1% (95% CI, 93.8-97.6%) for SFTS. CONCLUSION:This prediction scoring tool may be useful for differentiating SFTS from eschar- or skin rash-negative scrub typhus. It is a simple and readily applicable tool with potential for use in primary care settings.
10.1186/s12879-019-3773-1
Preliminary fast diagnosis of severe fever with thrombocytopenia syndrome with clinical and epidemiological parameters.
Hu Jianli,Li Zhifeng,Hong Lei,Bao Changjun,Zhang Zhong,Zhang Hongying,He Hao,Wang Xiaochen,Liu Wendong,Peng Zhihang,Shi Limin,Zhu Fengcai
PloS one
OBJECTIVES:To identify specific clinical and epidemiological parameters for clinical diagnosis of SFTSV infection with relatively higher accuracy. METHODS:231 suspected cases of SFTS were reported by various medical institutions from 2011 to 2013 in Jiangsu Province, China. They were followed with SFTSV diagnosis tests and interview-administered questionnaires about demographic characteristics, clinical symptoms and epidemiological exposure factors. Univariate and multivariable logistic regression analysis were used to examine the diagnostic value of these parameters. RESULTS:SFTSV infection occurred only from April to October annually and usually in hilly areas of specific regions. Three prediction models of SFTSV infection were constructed. Model 3 with clinical and epidemiological parameters combined the benefits of both Model 1and Model 2, which was optimal and had an overall accuracy of 80.2%. Independent indicators for clinical diagnosis of SFTSV infection in Model 3 were as follows: lymphadenopathy (P = 0.01), leucopenia (P<0.01), age >50 years (P = 0.01), tick bites (P<0.01), raising domestic animals in the residential areas (P<0.01) and farming (P = 0.03). CONCLUSIONS:Our results show that using a combination of clinical and epidemiological parameters may be a feasible strategy to provide preliminary fast diagnosis as differentiating SFTSV infection from SFTS-like diseases, thus reducing the risk of misdiagnosis.
10.1371/journal.pone.0180256
Seroprevalence of severe fever with thrombocytopenia syndrome virus in China: A systematic review and meta-analysis.
Li Peng,Tong Zhen-Dong,Li Ke-Feng,Tang An,Dai Ya-Xin,Yan Jian-Bo
PloS one
OBJECTIVE:Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by a novel bunyavirus-SFTSV. The seroprevalence of anti-SFTSV antibodies including immunoglobulin G (IgG) and immunoglobulin M (IgM), specific to SFTSV in the general population has been investigated in various epidemiological studies with inconsistent results. Here, we clarify this discrepancy and reach a more comprehensive result by mean of a meta-analysis. METHODS:All relevant articles were searched in the electronic databases (PubMed, Web of science, Embase, Chinese National Knowledge Infrastructure database, Chinese Wanfang database) up to November 2016. The pooled seroprevalence and 95% confidence intervals (95% CIs) were calculated by random- or fixed- model on the basis of heterogeneity. RESULTS:In total, 21 studies containing 23,848 blood samples from 7 provinces were included in this meta-analysis. The minimum and maximum reported seroprevalences of SFTSV among humans in China were 0.23% and 9.17%, respectively. The overall pooled seroprevalence of SFTSV antibodies was 4.3% (95%CI: 3.2%-5.5%). The pooled prevalence was 5.9% (95%CI: 4.7%-7.0%) in Zhejiang province, 4.9% (95%CI: 4.1-5.8%) in Anhui province, 3.9% (95%CI: 1.3%-6.4%) in Shandong province, and 0.7% (95%CI: 0.2%-1.1%) in Jiangsu province. Stratified by occupation, the pooled prevalence of farmer was 6.1% (95%CI: 3.4%-8.9%) and others (mainly are students) was 3.3% (95%CI: 2.4%-4.2%). Additionally, seroprevalence of SFTSV in people who lived in the same village with the patient were higher than that of people who lived in a different village. Seropositive rates in sampling years after 2012 were higher than that before 2012. The prevalence of SFTSV did not differ by age or gender. Sensitive analysis by omitting one study at a time indicated the results of the pooled seroprevalence were robust. CONCLUSIONS:Seroprevalence of SFTSV among healthy population in central and eastern China is high. Surveillance efforts on mild or asymptomatic infections among endemic persons are needed.
10.1371/journal.pone.0175592
Factors associated with Severe Fever with Thrombocytopenia Syndrome infection and fatal outcome.
Sun Jimin,Gong Zhenyu,Ling Feng,Zhang Rong,Tong Zhendong,Chang Yue,Chen Enfu,Liu Qiyong,Lin Junfen,Chen Zhiping,Jiang Jianmin
Scientific reports
Severe fever with thrombocytopenia syndrome (SFTS) is emerging in China and the incidence increased year by year. In this study, we conducted case control study to explore factors associated with SFTS virus (SFTSV) infection and fatal outcome. In the study of factors associated with SFTSV infection, a total of 216 individuals participated the study, including 72 cases and 144 matched controls. There were significant differences in proportion of history of tick bite and breeding domestic animals between cases and controls. Of note, individuals who were unclear whether they had been bitten by ticks had the highest risk of SFTSV infection and odds ratio (OR) was 10.222. In the study of factors associated with SFTS fatal outcome, a total of 129 cases participated the study including 16 deaths and 113 survivors. Significant differences were observed in body mass index (BMI), intervals from illness onset to confirmation, and proportion of gingival hemorrhage between deaths and survivors, whose ORs of these factors were 3.903, 1.996, and 3.826, respectively. Our results suggest that all patients with fever, thrombocytopenia and leukocytopenia in SFTS endemic areas should be suspected of SFTS, even they don't have history of tick bite, and more intense treatment should be administered to patients with abnormal BMI before laboratory parameters are detected.
10.1038/srep33175
Dyspnea and Wheezing as the Earliest Manifestations of Severe Fever with Thrombocytopenia Syndrome: The First Case Report.
Yamashita Shun,Katsuki Naoko E,Tago Masaki,Yamashita Shu-Ichi
Internal medicine (Tokyo, Japan)
A 64-year-old Japanese woman developed fatigue, dyspnea, and wheezing in July. Although she had been undergoing treatment for chronic obstructive pulmonary disease for six days, she was transferred to our hospital with delirium and diarrhea. On admission, she had an eschar of 3 mm in diameter on her anterior chest. Polymerase chain reaction of her blood and eschar specimens led to the diagnosis of severe fever with thrombocytopenia syndrome. Chest computed tomography showed ground-glass opacities, suggesting noncardiogenic pulmonary edema or viral pneumonia. This is the first case report of severe fever with thrombocytopenia syndrome beginning with dyspnea and wheezing.
10.2169/internalmedicine.2660-19
Vascular endothelial injury in severe fever with thrombocytopenia syndrome caused by the novel bunyavirus.
Li Xiao-Kun,Zhang Shao-Fei,Xu Wen,Xing Bo,Lu Qing-Bin,Zhang Pan-He,Li Hao,Zhang Li,Zhang Wen-Cong,Chen Wei-Wei,Cao Wu-Chun,Liu Wei
Virology
Severe fever with thrombocytopenia syndrome virus (SFTSV) infection typically causes acute fever, thrombocytopenia and leucopenia, presenting with a high case fatality rate. The pathogenesis of SFTSV infection, however, is not well described. It was hypothesized that endothelial dysfunction might play part in the disease process. In current study, we retrospectively analyzed the clinical manifestations among a large group of confirmed SFTS cases and found evidence of plasma leakage and vascular endothelial injury. Then we established a SFTSV infection cell model and determined the infectivity and stimulation of SFTSV on vascular endothelial cells in vitro. The hyperpermeability of endothelial cells directly induced by SFTSV was confirmed by electrical resistance and dextran diffusion assay. The virus induced alterations of cell junctions and cytoskeleton was also revealed. It's suggested that vascular endothelial cell injury and barrier function damage were induced after SFTSV infection, which is a vital but neglected pathogenesis of SFTS.
10.1016/j.virol.2018.05.001
Dynamic changes of laboratory parameters and peripheral blood lymphocyte subsets in severe fever with thrombocytopenia syndrome patients.
Liu Jingwen,Wang Li,Feng Zhaolei,Geng Daying,Sun Ye,Yuan Guangying
International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases
OBJECTIVES:The aim of this study was to dynamically investigate laboratory parameters and peripheral blood lymphocyte subsets in severe fever with thrombocytopenia syndrome (SFTS) patients at different stages, to evaluate the significance of these changes in the infection process and its influence on prognosis. METHODS:Case-control study was used in the research. Sixty-nine confirmed thrombocytopenia syndrome virus(SFTSV) infected patients were enrolled. They were divided into two groups, recovery group and poor prognosis group, according to the clinical prognosis of the diseases. The laboratory parameters were measured by matched fully-automatic detector. The dynamic lymphocyte subsets of each group were tested by flow cytometry. Independent-group Student's t-test, Bonferroni test and Nemenyi test were used to compare the mean value of every group. RESULTS:The clinical manifestations typically became worse on about the 7th day. Most of them had multi organ dysfunction, and part of them had hemophagocytic lymphohistiocytosis histiocytosis (HLH). The characteristic laboratory findings in the early stage were the drop of platelets (PLT), while the increase of alanine aminotransferase (ALT), aspartate amino transferase (AST), creatine kinase (CK), and lactate dehydrogenase (LDH). SFTSV viral loads reached the highest on Days 7-10 after onset of fever in SFTS patients. CD3+, CD3+CD4+ T cell counts were significantly reduced in poor prognosis group, more so on Days 7-10 after onset of fever. CD3-CD19+ (B cell) counts in SFTS patients were significantly higher than that of healthy controls. 11 days after illness onset, symptoms were improved, accompanied by resolution of laboratory abnormalities. CONCLUSIONS:These results indicated that SFTS had an acute onset and self-limited course. It was a systemic infection. The host immune response caused tissues and organs injury. The improvement of symptoms and laboratory tests was consistent with the elimination of the virus and recover of immune response. Further investigation should be done in order to reveal the mechanisms of SFTSV pathogenesis and guide the clinical treatment.
10.1016/j.ijid.2017.02.017
Epidemiological and clinical features of laboratory-diagnosed severe fever with thrombocytopenia syndrome in China, 2011-17: a prospective observational study.
Li Hao,Lu Qing-Bin,Xing Bo,Zhang Shao-Fei,Liu Kun,Du Juan,Li Xiao-Kun,Cui Ning,Yang Zhen-Dong,Wang Li-Yuan,Hu Jian-Gong,Cao Wu-Chun,Liu Wei
The Lancet. Infectious diseases
BACKGROUND:Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with an increasing case number and extensive geographical expansion, raising concerns locally and globally; however, the description of its clinical features needs to be addressed by large studies. We aimed to determine all the clinical features of SFTS in a large population of patients in an endemic area. METHODS:In this prospective observational study, data were collected on patients admitted to the People's Liberation Army Hospital in Xinyang, Henan Province, China, with laboratory-diagnosed SFTS. Demographic, clinical, laboratory, and treatment data were collected for each patient, and patients were followed up within 2 weeks after discharge or discontinuation of treatment. The association between each demographic, clinical, and laboratory variable with a fatal outcome was assessed. A clinical scoring model was designed for the early prediction of a fatal outcome, and the effect of treatment on outcome was analysed. FINDINGS:Between April 1, 2011, and Oct 31, 2017, 2096 patients with laboratory-confirmed SFTS were admitted. Mean age at admission was 61·4 years (SD 12·2) and 1239 (59%) patients were female. The case fatality rate (CFR) was 16·2% (95% CI 14·6-17·8). A higher risk was associated with being male (unadjusted odds ratio [OR] 1·45, 95% CI 1·15-1·83; p=0·002), older age (for a 10-year increase, unadjusted OR 1·82, 95% CI 1·62-2·04; p<0·0001), longer delay in admission (for every extra day taken before admission to hospital, unadjusted OR 1·18, 1·12-1·24; p<0·0001), presence of diarrhoea (adjusted OR 1·44, 1·12-1·87; p=0·005) or dyspnoea (adjusted OR 8·35, 5·97-11·69; p<0·0001), and development of haemorrhagic signs (adjusted OR 2·79, 95% CI 2·18-3·57; p<0·0001) or neurological symptoms (adjusted OR 30·26, 21·39-42·81; p<0·0001). Laboratory variables that were associated with death included abnormal concentrations of lactate dehydrogenase, aspartate aminotransferase, and blood urea nitrogen, and abnormal neutrophil percentage, which together with age and neurological symptoms were combined in the clinical scoring system. A total score of more than 8 was the optimal threshold to predict risk of death for patients who were evaluated within 6 days after symptom onset (area under the curve 0·879, 95% CI 0·855-0·902). For all participants, viraemia was a strong predictor of fatal outcome (all p<0·0001). Ribavirin therapy was effective in reducing CFR from 6·25% (15 of 240 participants) to 1·16% (two of 173 participants), but only in patients with a viral load below 1×10 copies per mL (hazard ratio 9·72, 95% CI 1·30-72·87; p=0·027). INTERPRETATION:The changing epidemiological features and high CFR of SFTS underscore the necessity of continued surveillance. Early prediction of fatal outcome can be attained by monitoring of clinical and laboratory data. Ribavirin should be applied early, with best results achieved before the viral load reaches 1 × 10 copies per mL. FUNDING:National Natural Science Foundation of China.
10.1016/S1473-3099(18)30293-7
[Epidemiological analysis on severe fever with thrombocytopenia syndrome under the national surveillance data from 2011 to 2014, China].
Li Yu,Zhou Hang,Mu Di,Yin Wenwu,Yu Hongjie
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi
OBJECTIVE:To analyze the epidemiological features and surveillance management programs on severe fever with thrombocytopenia syndrome (SFTS) in China from 2011 to 2014. METHODS:The analysis of epidemiological characteristics and surveillance management programs was based on the annual reporting data collected from the National Disease Reporting Information System while the description of cluster incidents was based on those reports collected from the Public Health Emergency Information Management System (PHEIMS). Association between age groups and fatality rate was tested under the Cochran-Armitage Trend Test. The difference of fatality rates between differing groups was analyzed, using the chi-square test, with statistical significance on α = 0.05. RESULTS:Between 2011 and 2014, 5 352 suspected, probable and lab-confirmed cases of SFTS were reported in 23 provinces, of which 16 provinces reported 2 750 lab-confirmed cases with a fatality of 7.9%, accounting for 51.4% of all the cases, nation-wide. Henan, Shandong, Hubei, Anhui, Liaoning, Zhejiang and Jiangsu reported 99.3% of those lab-confirmed cases. The period between April and October appeared the epidemic season, with its peak from May to July. Most cases were farmers, accounted for 88.3% of the lab-confirmed cases. People at the age between 50-74 occupied 67.6% of all the cases. Fatality of the disease continually increased from 3.7% in the age group 40-44 to 13.5% in the age group older than 80. Fatality rates appeared statistically different between the groups with or without misdiagnosis, with OR as 3.06 (95% CI: 1.61-5.90). Secondary cases of the cluster incidents were most likely to result from contacting the blood of the index cases. CONCLUSION:Number of reported SFTS cases showed a rising trend in China. Henan, Hubei, Anhui, Shandong and Liaoning provinces appeared at high risk of the disease. Geographical distribution of the SFTS cases' seemed highly sporadic, with May to July being the peak season. Farmers and elderly were considered as high risk population. Occasionally, cluster incidents might be seen, as the result of contacting the blood of cases or corpses. Being at older age and misdiagnosis seemed to be risk factors for fatality.
A Cluster of Symptomatic and Asymptomatic Infections of Severe Fever with Thrombocytopenia Syndrome Caused by Person-to-Person Transmission.
Huang Deyu,Jiang Yueping,Liu Xiaoping,Wang Bo,Shi Junming,Su Zhan,Wang Hui,Wang Ting,Tang Shuang,Liu Hanyun,Hu Zhihong,Deng Fei,Shen Shu
The American journal of tropical medicine and hygiene
Severe fever with thrombocytopenia syndrome virus (SFTSV) is a novel phlebovirus that was identified to be the etiological pathogen of the emerging infectious disease, severe fever with thrombocytopenia syndrome (SFTS). SFTSV could be transmitted through tick bite. Transmission of SFTSV among humans has also been reported mainly through direct blood contact. In July 2014, a cluster of six suspected SFTS cases occurred in Shandong Province, China. In this cluster, both symptomatic and asymptomatic persons were included. By analyzing the clinical data and results of laboratory tests, and conducting the epidemiological interviews with the cases and their families, risk factors responsible for the transmission were evaluated. The findings suggested that SFTSV transmission among humans may cause asymptomatic infection via personal contact without blood exposure.
10.4269/ajtmh.17-0059
Analysis of the laboratory indexes and risk factors in 189 cases of severe fever with thrombocytopenia syndrome.
Medicine
The current study aimed to analyze the clinical characteristics of severe fever with thrombocytopenia syndrome (SFTS) and to explore the risk factors of critical patients. From 2016 to 2018, we collected the hospitalized diagnosed cases with SFTS in Jinan infectious disease hospital of Shandong University and analyzed by the descriptive epidemiological method. According to the prognosis, they were divided into general group and severe group. The epidemiological characteristics, clinical features, and laboratory indexes of these 2 groups of patients were compared and analyzed at the first visit. The risk factors related to the severity of the disease were analyzed by univariate Logistic regression. In total, 189 cases of SFTS were treated during the period and 33 deaths occurred in the severe group, with the fatality rate of 17.46%. The patients' age (χ = 8.864, P < .01), ALT (Z = -2.304, P = .03), AST (Z = -3.361, P < .01), GLU (t = -4.115, P < .01), CK (Z = -3.964, P < .01), CK-MB (Z = -2.225, P = .03), LDH (Z = -3.655, P < .01), α-HBDH (Z = -2.040, P = .04), APTT (t = -3.355, P < .01), BUN (Z = -2.040, P = .04), Cr (Z = -3.071, P = .01), and D-dimer (Z = -2.026, P = .04) in the severe group were higher than that in the normal group, but the blood platelet (PLT) counts were significantly lower (Z = -2.778, P < .01) than that in the normal group. With the neuropsychiatric symptoms (OR = 24.083, 95% CI = 6.064-95.642), skin bleeding point (OR = 30.000, 95% CI = 6.936-129.764), multiple organ dysfunction (OR = 34.048, 95% CI = 7.740-149.782), past medical history (OR = 3.792, 95% CI = 1.284-11.200), and fasting glucose elevation (OR = 1.359, 95% CI = 1.106-1.668) could predict the severity of the SFTS. In summary, the abnormality of the laboratory index, the special clinical manifestations, and the past medical history of SFTS patients were the important basis for judging the patient's serious condition.
10.1097/MD.0000000000018727
[A review on the epidemiologic features of severe fever with thrombocytopenia syndrome].
Wang J Y,Wu H,Tong Z D,Yan J B,Li K F,Tang A
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi
Severe fever with Thrombocytopenia Syndrome (SFTS) is an emerging hemorrhagic fever disease in the rural areas of east-central China, which is caused by SFTSV-a newly discovered bunyavirus. SFTSV is most likely transmitted by tick bites but can also be transmitted within human beings. The onset of SFTS is sudden and with rapid progress, with main clinical manifestations as fever, thrombocytopenia, leucopenia and gastrointestinal and hepatorenal dysfunctions. Some patients may die from multiple organ failure, and the case fatality rate is approximately 10%. In this paper, we use the method of literature review to summarize the recent research progress of SFTS which includes the epidemic distribution characteristics, medium of transmission, host animals, transmission routes and susceptibility in the general population.
10.3760/cma.j.issn.0254-6450.2016.02.029
Score risk model for predicting severe fever with thrombocytopenia syndrome mortality.
Wang Li,Zou Zhiqiang,Hou Chunguo,Liu Xiangzhong,Jiang Fen,Yu Hong
BMC infectious diseases
BACKGROUND:Severe fever with thrombocytopenia syndrome (SFTS) is an emerging epidemic infectious disease with high mortality in East Aisa, especially in China. To predict the prognosis of SFTS precisely is important in clinical practice. METHODS:From May 2013 to November 2015, 233 suspected SFTS patients were tested for SFTS virus using RT-PCR. Cox regression model was utilized to comfirm independent risk factors for mortality. A risk score model for mortality was constructed based on regression coefficient of risk factors. Log-rank test was used to evaluate the significance of this model. RESULTS:One hundred seventy-four patients were confirmed with SFTS, of which 40 patients died (23%). Baseline age, serum aspartate aminotransferase (AST) and serum creatinine (sCr) level were independent risk factors of mortality. The area under ROC curve (AUCs) of these parameters for predicting death were 0.771, 0.797 and 0.764, respectively. And hazard ratio (HR) were 1.128, 1.002 and 1.013, respectively. The cutoff value of the risk model was 10. AUC of the model for predicting mortality was 0.892, with sensitivity and specificity of 82.5 and 86.6%, respectively. Log-rank test indicated strong statistical significance (× = 88.35, p < 0.001). CONCLUSIONS:This risk score model may be helpful to predicting the prognosis of SFTS patients.
10.1186/s12879-016-2111-0
Clinical and laboratory characteristics of severe fever with thrombocytopenia syndrome in Chinese patients.
The Brazilian journal of infectious diseases : an official publication of the Brazilian Society of Infectious Diseases
Severe fever with thrombocytopenia syndrome (SFTS) associated with severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging infectious disease. 12 patients with severe fever with thrombocytopenia syndrome in our study were presented mainly with fever and severe malaise. The clinical manifestations typically became worse on the 6th or 7th day. The average fever time is 9.11 ± 1.54 days. Most of them had multiorgan dysfunction, and part of them had hemophagocytic lymphohistiocytosis histiocytosis (HLH). The characteristic laboratory findings in the early stage were the drop of white blood cells (WBC), platelets (PLT) and serum Ca++, while increase of aspartate amino transferase (AST), creatine kinase (CK), and lactate dehydrogenase (LDH). CD3+CD4+ were significantly decreased, while CD3-CD56+ were significantly increased, whereas CD3+CD8+ were constantly elevated throughout the disease course. Ten to 14 days after illness onset, symptoms were improved, accompanied by resolution of laboratory abnormalities. These results indicate that severe fever with thrombocytopenia syndrome has an acute onset and self-limited course. It is a systemic infection. The host immune response caused tissues and organs injury. The improvement of symptoms and laboratory tests is consistent with the elimination of the virus and recover of immune response. Further investigation should be done in order to better understand this disease and guide the clinical treatment.
10.1016/j.bjid.2013.05.011
Characterization of clinical features and outcome for human-to-human transmitted severe fever with thrombocytopenia syndrome.
Jia Bei,Wu Weihua,Huang Rui,Wang Guiyang,Song Peixin,Li Yang,Liu Yong,Xiong Yali,Yan Xiaomin,Hao Yingying,Xia Juan,Zhang Zhaoping,Chen Yuxin,Wu Chao
Infectious diseases (London, England)
BACKGROUND:Severe fever with thrombocytopenia syndrome (SFTS) is a life-threatening infectious disease identified in 2009. SFTS is mainly transmitted by contact with ticks or animals; however, sporadic reports suggested that SFTS could be transmitted among humans. OBJECTIVES:We aimed to comprehensively characterize clinical features and disease progression of SFTS acquired by human-to-human transmission. STUDY DESIGN:A retrospective study of 90 SFTS patients was performed in a tertiary hospital of Nanjing, China, from October 2010 to October 2016. Seven cases of secondary SFTS were identified based on their epidemic timeline. Their clinical presentations, dynamic laboratory results and clinical outcome were analyzed. RESULTS:First, 20 out of 83 primary SFTS patients were deceased, leading to a case-fatality ratio of 24.1%, while all secondary patients survived, suggesting a superior clinical outcome for secondary infection. Moreover, clinical symptoms and laboratory tests in primary and secondary SFTS patients were analyzed, respectively. Secondary SFTS patients developed milder clinical manifestation in the absence of neurological disorder and multiple organ failure. Further, clinical laboratory tests revealed that secondary patients had less disturbed key laboratory parameters, compared to those in primary SFTS patients. During day 7-13 post illness onset, most of the clinical laboratory results of secondary patients went back to normal range. They also had significantly lower level of viral load than primary patients. CONCLUSIONS:Secondary SFTS acquired through human-to-human transmission leads to milder clinical representations and superior prognoses compared to primary SFTS, suggesting that the transmission route makes a difference in disease progression and clinical outcome of SFTS disease.
10.1080/23744235.2018.1449962
Serum cytokines and clinical features in patients with fever and thrombocytopenia syndrome.
Chen Huanzhu,Lin Chun,Fan Zhiqiang,Yu Wenjun,Cao Manxiong,Ke Changwen,Jiao Xiaoyang
Clinica chimica acta; international journal of clinical chemistry
PURPOSE:To explore the clinical, microbiological and immunological features of patients with fever and thrombocytopenia. METHODS:Patients with unexplained fever and thrombocytopenia were enrolled. Viruses were detected using real-time PCR, and bacteria were measured by culturing methods. Serum cytokines, platelet antibody IgG (PA-IgG) and Helicobacter pylori (HP) were detected using ELISA. RESULTS:Pathogens were detected in 74.68% of patients, which included single fungal/viral/bacterial infection and multiple infection. The pathogens could not be unidentified in 25.32% of cases. Cytokines including Interleukin (IL)-6, IL-10, interferon-γ(IFN-γ), platelet activating factor (PAF) and PA-IgG were significantly higher in patients as compared to healthy controls (P < .01 or P < .05). Principal component analyses extracted four groups of parameters that have a strong positive predicting value, revealing that disease status evaluation would be more accurate if we combined the platelet parameters and inflammatory biomarkers. While event-free survival (EFS) that indicates the time of platelet elevated after therapy was the highest in patients with single bacterial or fungal infection, EFS was affected by the levels of cytokines and PA-IgG. CONCLUSIONS:Differences in immune function may be the main factors affecting the prognosis of patients with fever and thrombocytopenia, while treatment based on precise etiological diagnosis is important for therapeutic efficacy.
10.1016/j.cca.2019.02.034
Application of the severe fever with thrombocytopenia syndrome prediction score: Differentiation of febrile diseases using basic laboratory parameters.
Chang Euijin,Kim Jeong-Han,Bang Ji Hwan,Park Wan Beom,Kim Eu Suk,Park Sang Won,Oh Myoung-Don
PloS one
BACKGROUND:The prolonged manifestation of concurrent leukopenia, thrombocytopenia and normal C-reactive protein (CRP) (named as SFTS prediction score) in febrile diseases is not usual and may be used to make an initial differential diagnosis, which is a characteristic finding of severe fever with thrombocytopenia syndrome (SFTS). METHODS:The dynamics of SFTS prediction scores was investigated in SFTS patients. The study subjects for the comparison were febrile patients aged ≥ 16 years with SFTS scores of 2 (S2) or 3 (S3) who visited an emergency room for a 4-year study period. The dynamic distribution of S2 and S3 at presentation with regards to onset of illness, the characteristics of responsible diseases and the predictability of SFTS in both groups were described. RESULTS:In 104 patients with SFTS, the daily proportion of S2 or S3 ranged from 58.3 to 100% from day (D) 1 to D12 after the onset of illness. The S2 subtype of 'leukopenia plus thrombocytopenia' and S3 represented 72.7-100% of all scores. In contrast, for the 130 patients in the febrile cohort, 73.8% of evaluations were distributed between D1 and D4 after the onset of illness, and 68.8% of patients had the S2 subtype of 'leukopenia plus normal CRP'. Upper respiratory infection was the most frequent (50.0%) cause of diseases. Pneumonia (13.8%) and urosepsis (6.2%) initially presented with either S2 with normal CRP or S3 but had poor prognosis. The presence of S2 or S3 predicted SFTS with sensitivity and specificity of 0.85 (0.42-0.99; 95% CI) and 0.98 (0.98-0.98; 95% CI), respectively. CONCLUSION:The temporal distribution and composition of S2 or S3 were unique in several febrile diseases including SFTS, and the SFTS prediction score may be useful for differentiating febrile diseases in primary care settings of SFTS endemic areas.
10.1371/journal.pone.0229920
The platelet derived growth factor-B polymorphism is associated with risk of severe fever with thrombocytopenia syndrome in Chinese individuals.
Zhang Xiao-Ai,Guo Chen-Tao,Lu Qing-Bin,Hu Jian-Gong,Cui Ning,Yang Zhen-Dong,Peng Wei,Liu Rong,Hu Chun-Yan,Qin Shu-Li,Wang Xian-Jun,Ding Shu-Jun,Huang Dou-Dou,Liu Wei,Cao Wu-Chun
Oncotarget
BACKGROUND:Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by a novel bunyavirus named SFTS virus (SFTSV). We hypothesize that host genetic variations may contribute to susceptibility to SFTS. RESULTS:Compared with the rs1800818 AA genotype, AG + GG genotypes were significantly associated with increased susceptibility to SFTS (odds ratio, 1.66, 95% confidence interval = 1.28-2.16; P < 0.001). By using the ELISA assay, we observed that PDGF-BB concentration was significantly reduced in acute phase of patients than in the controls (P < 0.001) and recovered patients at 6 month (P = 0.007) and 12 month (P = 0.003). A persistently reduced PDGF-BB was also revealed from the SFTSV-infected C57BL/6J mice (P < 0.001). The rs1800818 G allele was associated with decreased serum PDGF-BB levels in SFTS patients at their early infection (P = 0.015). In accordance, the relative mRNA levels of the at-risk G allele of 1800818 were lower than those of the A allele in heterozygous cell from acute phase of SFTS patients. PDGF-B rs1800818 conferred no susceptibility to severe or fatal outcome in SFTS patients. MATERIALS AND METHODS:An initially small-scale case-control association study guided the selection of platelet derived growth factor-B (PDGF-B) rs1800818 in 1020 SFTS patients and 1353 controls. Functional analyses were conducted to verify the biological significance of rs1800818 polymorphism. CONCLUSIONS:Our findings suggest that the PDGF-B rs1800818 polymorphism might play a role in mediating the susceptibility to SFTS.
10.18632/oncotarget.9043