Crimean-Congo Hemorrhagic Fever virus
Crimean-Congo Hemorrhagic Fever virus (CCHFV) is a tick-borne pathogen belonging to the Nairoviridae family within the Bunyavirales order. The virus was first discovered in the 1940s when Soviet soldiers became ill with a hemorrhagic disease after occupying Crimea. In the 1960s, a virus with identical clinical manifestations was discovered in the Belgian Congo (now known as the Democratic Republic of Congo) and was determined to be antigenically identical to that of the virus discovered in Crimea, thus giving rise to the name CCHFV. As with all Bunyaviruses, its genome is tripartite consisting of single-stranded (−) RNA segments-annotated based on length as small (S), medium (M), and large (L)-and due to each segment possessing complementary 5' and 3' ends, the genome forms iconic circular (panhandle) structures. The segments encode nucleocapsid (N protein), glycoprotein precursor (GPC), and RNA-dependent RNA polymerase, respectively. CCHF virions are spherical with a diameter of 80 to 100 nm with an envelope studded with glycoproteins (GPs) Gn and Gc.