Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with the high case-fatality rate, and lack of vaccines. We aimed to systematically analysed the epidemiological characteristics, clinical signs, routine laboratory diagnosis, risk factors, and outcomes. Methods: Documents on SFTS were collected by searching the Chinese National Knowledge Infrastructure, Wan Fang Data, PubMed, Embase, and Web of Science databases from 2011 to 2018. Meta-analysis was performed by using Review Manager and Stata software. Results: Twenty-five articles involving 4143 cases were included. Diarrhea (odds ratio (OR) =1.60, 95% confidence interval (CI): 1.06 to 2.42, P = 0.02), and vomiting (OR = 1.56, 95% CI: 1.01 to 2.39, P = 0.04) on admission were associated with the fatal outcomes of SFTS. Compared to patients with mild symptoms, patients with severe symptoms had significantly elevated levels of lactic acid dehydrogenase (standard mean difference (SMD) =1.27, 95% CI: 0.59 to 1.94), alanine aminotransferase (SMD = 0.55, 95% CI: 0.24 to 0.85), aspirate aminotransferase (SMD = 1.01, 95% CI: 0.69 to 1.32), and creatine kinase (SMD = 1.04, 95% CI: 0.74 to 1.33) but had reduced platelet counts (SMD = -0.87, 95% CI: − 1.16 to − 0.58) and albumin levels (SMD = -1.00, 95% CI: − 1.32 to − 0.68). The risk factors for poor prognosis included age (mean difference (MD) =6.88, 95% CI: 5.41 to 8.35) and farming (OR = 2.01, 95% CI: 1.06 to 3.80). For the risk factors of contracting SFTS, the incidence of SFTS related to tick bites was 24% [95% CI: 0.18 to 0.31]. The pooled case-fatality rate of SFTS patients was 18% [95% CI: 0.16 to 0.21]. Conclusions: China is the country with the highest incidence of SFTS. May to July was the peak of the epidemic, and farmers were a high-risk group. The risk factor for SFTS included age (poor prognosis) and tick bites (contracting SFTS). Patients with severe diarrhea and vomiting symptoms on admission should be noted. Clinicians could use routine laboratory parameters and clinical symptoms as references for clinically suspected cases, classification of SFTS, and timely treatment, especially in basic hospitals.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by severe fever with thrombocytopenia syndrome virus (SFTSV). SFTSV has been found in humans, ticks and animals, and SFTS has high mortality and increasing prevalence in East Asia. In the study, the samples (heart, liver, lung, kidney, spleen, brain tissue and serum) were collected from 374 domestic animals and 241 wild animals in Pingqiao District and Xinxian County of Xinyang in Henan Province, China. 275 (44.72%, 275/615) animals were positive for anti-SFTSV antibodies, the anti-SFTSV antibodies positive ratios of domestic and wild animals were 43.58% (163/374) and 46.47% (112/241), respectively. There was no significant difference in domestic and wild animals, but significant differences were detected among different species of animals (χ2 = 112.59, P < 0.0001). Among 615 animals, 105 (17.07%, 105/615) animals were positive for SFTSV RNA, and only one SFTSV strain was isolated from heart tissue of a yellow weasel. The phylogenetic analysis shows that the sequence from animals belonged to the same group with viral sequences obtained from humans. The animals maybe play a reservoir host in maintaining the life cycle of SFTSV in nature.

Objective: In January 2023, China implemented the “Class B Management” policy, marking a new phase in COVID-19 control. As new SARS-CoV-2 variants continue to emerge, some have shown significant immune evasion, posing challenges to epidemic control efforts. To manage the pandemic effectively, Henan Province launched a surveillance program for SARS-CoV-2 variants, systematically analyzing their clinical characteristics and epidemiological patterns.Methods: This study collected genomic sequence data from 5,965 COVID-19 cases between January 1, 2023, and March 17, 2024, using the Henan Province SARS-CoV-2 variant surveillance system. Genome sequence analysis was performed with CLC Genomics Workbench, and genotyping and sequence alignment were carried out using the Nextclade platform. The clinical severity of different variants was assessed in relation to patient sex, age, clinical classification, and vaccination status.Results: Between Week 1 of 2023 and Week 11 of 2024, a total of 5,965 complete SARS-CoV-2 genome sequences were obtained, including 3,004 male (50.36%) and 2,961 female (49.64%) cases. The majority of cases were mild (5,451 cases, 91.38%), followed by moderate (311 cases, 5.21%) and severe or critical cases (203 cases, 3.4%). The predominant variants included BA.5.2, XBB, and BA.2.86. BA.5.2 was dominant until April 2023, after which it was gradually replaced by XBB. From December 2023, BA.2.86 began to increase and became the predominant variant by January 2024. The XBB variant exhibited a significantly lower rate of severe cases, with most infections being mild (P < 0.05). Male patients, the elderly, and certain variants (e.g., BA.5.2) were associated with more severe outcomes, while XBB and BA.2.86 showed lower pathogenicity, with a marked reduction in severe and fatal cases (P < 0.05).Conclusion: As SARS-CoV-2 variants evolve, the incidence of severe cases has progressively decreased. Both XBB and BA.2.86 variants exhibit lower pathogenicity. This study provides vital scientific evidence on the epidemiological features, clinical manifestations, and control strategies of SARS-CoV-2 variants. It underscores the importance of continuous viral surveillance and genomic sequencing to guide public health decision-making.

Introduction: Avian influenza viruses (AIVs) continue to circulate in live poultry markets (LPMs), posing potential risks for zoonotic exposure. This study investigated the environmental circulation of AIVs and their potential epidemiological associations with human infection in Henan Province, China. Methods: We analyzed 7,956 environmental samples collected from poultry-associated settings in Henan Province between 2020 and 2025. Multivariable logistic regression was used to identify factors associated with AIV detection. Serological surveillance was conducted among occupationally exposed individuals, and phylogenetic analyses were performed to characterize the genetic relationships between human-derived and environmental AIVs. Results: A total of 1,460 samples (18.35%) tested positive for AIVs. LPMs were significantly associated with higher odds of AIV detection (OR = 7.211, 95% CI: 5.039–10.319, P < 0.001), and the odds of AIV detection increased over the surveillance period (OR = 1.254, 95% CI: 1.210–1.301, P < 0.001). Multiple AIV subtypes were detected, with H9N2 remaining predominant throughout the study period. Five human infections were identified, including H5N6 and H3N8 infections in 2022 and three H9N2 infections in 2025. Serological surveillance identified H9N2-seropositive and H3N8-reactive samples among occupationally exposed individuals. Phylogenetic analyses revealed genetic similarities between human-derived and environmental viruses. Three H3N8 viruses, including one isolated from a human case, formed a distinct phylogenetic cluster, with their internal genes closely related to co-circulating H9N2 viruses. Discussion: These findings demonstrate sustained circulation of multiple AIV subtypes in poultry-associated environments and highlight the importance of integrated environmental and human surveillance for the early detection of viruses with zoonotic potential.

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a severe emerging disease, and its incidence has been increasing in recent years. A cross-sectional study was conducted for healthy people in high SFTS endemic areas of Henan province in 2016. Methods: This study used stratified random sampling method and finally 14 natural villages were selected as the investigation site. The questionnaire survey and serum collection were carried out from April to May in 2016. All the serum samples were detected by SFTSV IgM and IgG antibodies by ELISA. Only positive samples of SFTSV IgM antibody need be tested SFTSV RNA and virus cultured. A month after the specimen collection, all persons positive for IgM antibody were followed up one by one to confirm whether he or she was recessive infection. Results: 1463 healthy persons were investigated in total. The average seropositive rates of SFTS virus specific IgG and IgM antibodies were 10.46% (153/1463) and 0.82% (12/1463), respectively. IgM antibody was positive in 12 individuals, and 6 of them SFTS virus RNA were also detected. In addition, 5 SFTS virus were isolated from the 6 SFTS virus RNA (+) individuals. By genomic sequencing and phylogenetic analysis, 5 new isolates from healthy crowd all belonged to groups A, which were similar to other isolates from SFTS patients. After one month, all people with SFTS virus IgM antibody had no illness or symptoms. Conclusions: This study confirmed there is SFTS recessive infection in human, and it is the first report about SFTS virus isolation in healthy people. Author Summary: Severe fever with thrombocytopenia syndrome (SFTS), a severe emerging infectious disease, was discovered in rural areas of China. The first SFTS case was found in Henan province, which has had the largest number of SFTS cases in China every year since the disease was discovered. However, as a high incidence area of SFTS in Henan province, the serum prevalence rate of the virus in healthy people is still not clear. Therefore, a cross-sectional survey was performed in high endemic areas and epidemic seasons in 2016. The results showed that the level of specific SFTS seroprevlence was relatively higher and possibility increasing. SFTS RNA were positive and SFTS virus was isolated from the specimens of healthy people. This study confirmed there is SFTS recessive infection in human, and it is the first report about SFTS virus isolation in healthy people.