Pattern of Clinical Symptoms and Laboratory Findings Associated With Mortality of Crimean-Congo Hemorrhagic Fever in Northwest of Iran: A Five-Year Population-Based Survey

Crimean-Congo hemorrhagic fever is an occupational viral disease that has various clinical symptoms. This disease is transmitted by arthropods and has a high mortality rate in different geographical areas. A cross-sectional study that took place from 2017-2021 in the northwest of Iran. All suspected cases of CCHF that were referred to medical centers using the instructions of the Ministry of Health were collected and analyzed using an RT-PCR test. We performed latent class analysis using a procedure for latent class analysis (PROC LCA) in SAS to identify class membership of brucellosis symptoms. 41.4% of the patients had livestock-related jobs and 24.1% were housewives. The incidence rate of CCHF was 0.42 per 100000 population in 2017 and reached 1.3 in 2021. Three-class model of CCHF clinical Symptoms and laboratory findings. Patients in the severe class had a high probability of having fever, chill, anorexia, bleeding, weakness and lethargy, muscle pain, headache, nausea and vomiting, thrombocytopenia, low hemoglobin, and increased liver enzymes. 20.5% of patients had severe disease symptoms. Late diagnosis of CCHF increases the risk of mortality. The frequency and variety of clinical symptoms of this disease cause severe and dangerous forms.