T-Cells and Interferon Gamma Are Necessary for Survival Following Crimean-Congo Hemorrhagic Fever Virus Infection in Mice

Crimean-Congo hemorrhagic fever (CCHF) is a severe tick-borne febrile illness with wide geographic distribution. In humans, the disease follows infection by the Crimean-Congo hemorrhagic fever virus (CCHFV) and begins as flu-like symptoms that can rapidly progress to hemorrhaging and death. Case fatality rates can be as high as 30%. An important gap in our understanding of CCHF are the host immune responses necessary to control the infection. A better understanding of these responses is needed to direct therapeutic strategies to limit the often-severe morbidity and mortality seen in humans. In this report, we have utilized a mouse model in which mice develop severe disease but ultimately recover. T-cells were robustly activated, differentiated to produce antiviral cytokines, and were critical for survival following CCHFV infection. We further identified a key role for interferon gamma (IFN gamma) in survival following CCHFV infection. These results significantly improve our understanding of the host adaptive immune response to severe CCHFV infection.

Automated summary

Crimean-Congo hemorrhagic fever (CCHF) is a severe tick-borne febrile illness caused by the CCHFV, with host immune responses playing a crucial role in controlling the infection. Using a mouse model, it was found that T cells and interferon gamma are critical for survival following CCHFV infection.