CrimeanCongo

Crimean-Congo hemorrhagic fever (CCHF) is a viral hemorrhagic fever caused by Crimean-Congo hemorrhagic fever virus (CCHFV), a member of the genus Orthonairovirus in the family Nairoviridae. The virus has a segmented, negative-sense RNA genome and is primarily transmitted to humans by bite of Hyalomma ticks. Human-to-human transmission can occur through contact with blood, secretions, or other infectious materials from viremic patients or infected animals, especially during slaughter or medical care.

Ecology and distribution: CCHFV is endemic in large areas of Africa, the Balkans, the Middle East, and parts of Asia. The range of Hyalomma ticks and animal hosts supports seasonal transmission, with higher risk in spring and summer in many regions. Global travel and animal movement can introduce the virus to new areas.

Clinical features: After an incubation of roughly 1 to 12 days, infection commonly presents with fever, myalgia, malaise, headache, and occasionally gastrointestinal symptoms. In severe cases, hemorrhagic manifestations, liver and kidney dysfunction, and shock may occur. Case fatality rates vary widely, historically around 10% to 40%, and are higher in outbreaks with limited access to supportive care.

Diagnosis, treatment, and prevention: Diagnosis relies on laboratory detection of viral RNA or specific antibodies (RT-PCR, ELISA). There is no licensed vaccine for humans. Treatment is primarily supportive, with careful fluid management; ribavirin has been used in some cases with uncertain benefit. Prevention focuses on tick control, protective clothing and repellents for people in endemic areas, safe handling of animals and meat, and infection control in healthcare settings.

Public health context: CCHF remains an important cause of viral hemorrhagic fever in affected regions and is monitored by international and national health authorities as a reportable disease.