Abstract
There are uncertainties about the global epidemiological data of infections due to Crimean-Congo hemorrhagic fever virus (CCHFV). We estimated the global case fatality rate (CFR) of CCHFV infections and the prevalence of CCHFV in humans, ticks and other animal species. We also explored the socio-demographic and clinical factors that influence these parameters. In this systematic review with meta-analyses we searched publications from database inception to 03rd February 2020 in Pubmed, Scopus, and Global Index Medicus. Studies included in this review provided cross-sectional data on the CFR and/or prevalence of one or more targets used for the detection of CCHFV. Two independent investigators selected studies to be included. Data extraction and risk of bias assessment were conducted independently by all authors. Data collected were analysed using a random effect meta-analysis. In all, 2345 records were found and a total of 312 articles (802 prevalence and/or CFR data) that met the inclusion criteria were retained. The overall CFR was 11.7% (95% CI = 9.1-14.5), 8.0% (95% CI = 1.0-18.9), and 4.7% (95% CI = 0.0-37.6) in humans with acute, recent, and past CCHFV infections respectively. The overall CCHFV acute infections prevalence was 22.5% (95% CI = 15.7-30.1) in humans, 2.1% (95% CI = 1.3-2.9) in ticks, and 4.5% (95% CI = 1.9-7.9) in other animal species. The overall CCHFV recent infections seroprevalence was 11.6% (95% CI = 7.9-16.4) in humans and 0.4% (95% CI = 0.0-2.9) in other animal species. The overall CCHFV past infections seroprevalence was 4.3% (95% CI = 3.3-5.4) in humans and 12.0% (95% CI = 9.9-14.3) in other animal species. CFR was higher in low-income countries, countries in the WHO African, South-East Asia and Eastern Mediterranean regions, in adult and ambulatory patients. CCHFV detection rate in humans were higher in CCHFV suspected cases, healthcare workers, adult and hospitalized patients, ticks of the genus Ornithodoros and Amblyomma and in animals of the orders Perissodactyla and Bucerotiformes. This review highlights a significant disease burden due to CCHFV with a strong disparity according to country income levels, geographic regions, various human categories and tick and other animal species. Preventive measures in the light of these findings are expected.
Highlights
Crimean-Congo Hemorrhagic Fever (CCHF) is one of the most severe zoonotic viral diseases that occur in humans
This study provides a summary of epidemiological data of Crimean Congo hemorrhagic fever, in humans, ticks and other animal species derived from articles published from 1974 to 2020
This study shows that the majority of studies on the Crimean-Congo hemorrhagic fever virus (CCHFV) case fatality rates (CFR) and associated factors was conducted in Turkey followed by Iran, Afghanistan, Pakistan, India
Summary
Crimean-Congo Hemorrhagic Fever (CCHF) is one of the most severe zoonotic viral diseases that occur in humans. The Crimean-Congo hemorrhagic fever virus (CCHFV) was first identified in the Crimean region of Russia in 1944 and was subsequently shown to be identical to the Congo virus identified in the Congo basin in 1967, giving the virus its current name [2,3,4]. This virus has been detected in more than 50 countries of Asia, Europe, and Africa where it is associated either to outbreaks of hemorrhagic fever or only sporadic cases [2]. This is due to various factors such as climate change, the increase in the tick number, the increasing exposure of animals and humans and the improvement of viral detection assays
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
