Current Status of Crimean-Congo Hemorrhagic Fever and Its Vectors in Iran: A Narrative Review

Background and purpose: Crimean-Congo Hemorrhagic Fever (CCHF) is an acute viral disease caused by a virus of the genus Nairovirus, transmitted primarily through the bites of infected ticks. Due to its high mortality rate and prevalence in various regions worldwide, particularly in Iran, different aspects of the disease warrant more detailed investigation. In this narrative review, data collection was performed through comprehensive searches of scientific databases, including PubMed, Web of Science, Scopus, and ScienceDirect, as well as Persian databases such as the Scientific Information Database (SID), the National Journals Database (Magiran), and Civilica. The search employed both Persian and English keywords, including “Crimean-Congo fever,” “Crimean-Congo hemorrhagic fever,” “Nairoviruses,” “Prevalence,” “Epidemiology,” “Distribution,” “Vectors,” “Tick,” “Control,” and “Iran,” using both individual and advanced combined search strategies, covering the period from 1969 to December 2024. The findings indicate that the incidence of CCHF in Iran has risen in recent years, with cases reported from all 31 provinces. Sistan and Baluchestan and Khorasan Razavi Provinces have reported the highest number of cases. The disease shows peak prevalence during the warm seasons, particularly from mid-spring to mid-summer, coinciding with heightened tick activity, and is more frequently observed in men due to occupational exposure. Individuals such as butchers, livestock farmers, and those who handle livestock or infected patients are at high risk, especially in rural areas. Among the 37 tick species identified in Iran, 11 are infected with the CCHF virus. The highest number of CCHF-infected tick species has been reported in Hamedan Province. Hyalomma marginatum and Hyalomma anatolicum have been documented as the primary vectors of CCHF. Given the current status of CCHF in Iran and the influence of environmental and social factors in recent years, the establishment of comprehensive programs focusing on prevention, education, and public awareness is crucial to reducing the prevalence and controlling the spread of this disease.