Nairoviruses chronically infected Hyalomma derived cell lines

Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic viral disease that is asymptomatic in infected animals, but a serious threat to humans. Human infections begin with nonspecific febrile symptoms that progress to a serious hemorrhagic syndrome with a high case fatality rate. CCHF virus (CCHFV) is classified as a biosafety level 4 pathogen and is the second most widespread of all the medically important arboviruses after dengue virus. CCHFV has been found in at least 31 species of ticks, in particular, members of the genus Hyalomma seem to be the principal vectors as they play an important role as natural reservoir. In the present work, the infection susceptibility of two Hyalomma-derived cell lines to CCHFV and Hazara virus (HAZV), an apathogenic virus closely related to the CCHFV, has been investigated in order to compare CCHFV and HAZV virus/host interactions in the context of arthropod cells. Preliminary results showed that the tick cell lines tested were susceptible to infection without any cytopathic effect. It was also discovered that infected cells release progeny virus to supernatant for at least 90 days post infection. The real-time PCR data analysis suggest that these cells are persistently infected. Currently, a transcriptomics approach to study the cellular response to CCHFV or HAZV infection is under investigation. The results of the comparative studies on replication of CCHFV and HAZV in tick cells will be herein discussed