Detection of autochthonous virus strain responsible for the recent outbreak of Crimean-Congo haemorrhagic fever in North Macedonia, July to August 2023

Abstract Crimean-Congo Hemorrhagic Fever (CCHF) is a severe illness transmitted by ticks and infectious body fluids, characterized by fever, hemorrhagic syndrome, and high fatality rates. This study investigates the recent outbreak of CCHF in North Macedonia, where cases had not been reported for over 50 years, aiming to elucidate factors contributing to its re-emergence and inform public health strategies. Through a multidisciplinary approach encompassing epidemiological, clinical, and molecular analyses, we garnered pivotal insights into the outbreak dynamics. Centralized in Kuchica village, our serosurveys conducted among local livestock populations disclosed a significant rate of CCHFV exposure, which underlines the urgent necessity for persistent monitoring of the virus's circulation. The phylogenetic analysis distinctly pointed to the autochthonous nature of the CCHFV Hoti strain implicated in the outbreak. This local strain circulation may be influenced by ecological changes, probably climate change, which is likely altering tick distribution, activity patterns and the extrinsic incubation of the virus in North Macedonia. This report underscores the importance of clinical vigilance, proactive surveillance, early detection, and collaborative efforts in combating emerging infectious diseases like CCHF. By prioritizing monitoring, risk assessment, and preparedness measures, we can effectively mitigate the impact of CCHF and protect public health in affected regions.