Global epidemiology of severe fever with thrombocytopenia syndrome virus in human and animals: a systematic review and meta-analysis

Background Since the initial identi fi cation of the Severe Fever with Thrombocytopenia Syndrome (SFTS) in ticks in rural areas of China in 2009, the virus has been increasingly isolated from a diverse array of hosts globally, exhibiting a rising trend in incidence. This study aims to conduct a systematic analysis of the temporal and spatial distribution of SFTS cases, alongside an examination of the infection rates across various hosts, with the objective of addressing public concerns regarding the spread and impact of the disease. Methods In this systematic review and meta-analysis, an exhaustive search was conducted across multiple databases, including PubMed, Web of Science, Embase, and Medline, CNKI, WanFang, and CQVIP. The literature search was con fi ned to publications released between January 1, 2009, and May 29, 2023. The study focused on collating data pertaining to animal infections under natural conditions and human infection cases reported. Additionally, species names were uni fi ed using the National Center for Biotechnology Information (NCBI) database. The noti fi cation rate, noti fi cation death rate, case fatality rate, and infection rates (or MIR) were assessed for each study with available data. The proportions were pooled using a generalized linear mixed-effects model (GLMM). Meta-regressions were conducted for subgroup analysis. This research has been duly registered with PROSPERO, bearing the registration number CRD42023431010. Findings We identi fi ed 5492 studies from database searches and assessed 238 full-text studies for eligibility, of which 234 studies were included in the meta-analysis. For human infection data, the overall pooled noti fi cation rate was 18.93 (95% CI 17.02 - 21.05) per ten million people, the overall pooled noti fi cation deaths rate was 3.49 (95% CI 2.97 - 4.10) per ten million people, and the overall pooled case fatality rate was 7.80% (95% CI 7.01% - 8.69%). There was an increasing trend in noti fi cation rate and deaths rate, while the case fatality rate showed a signi fi cant decrease globally. Regarding animal infection data, among 94 species tested, 48 species were found to carry positive nucleic acid or antibodies. Out of these, 14 species were classi fi ed under Arthropoda , while 34 species fell under Chordata , comprising 27 Mammalia and 7 Aves . Interpretation This systematic review and meta-analysis present the latest global report on SFTS. In terms of human infections, noti fi cation rates and noti fi cation deaths rates are on the rise, while the case fatality rate has signi fi cantly decreased. More SFTSV animal hosts have been discovered than before, particularly among birds, indicating a potentially broader transmission range for SFTSV. These fi ndings provide crucial insights for the prevention and control of SFTS on a global scale. Health 2024;48:101133 Published https://doi.org/10. 1016/j.lanwpc.2024. 101133