Preclinical Crimean Congo Haemorraghic Fever Vaccine Development

Preclinical Crimean Congo Haemorraghic Fever Vaccine Development Crimean Congo Haemorraghic Fever virus (CCHFv) is a severe haemorraghic tick-borne disease which causes outbreaks with a case fatality rate of 10-40%. Ticks infect livestock, mainly sheep although many species may be infected, and humans may be infected by tick bites or contact with infected animal body fluids after which human to human transmission may occur. The disease is endemic in Africa, the Balkans, the Middle East and parts of Asia and no vaccine is available for either humans or livestock. The Jenner Institute has developed the replication-deficient simian adenoviral vector platform ChAdOx1 to produce vaccines against a number of outbreak pathogens. ChAdOx1-vectored vaccines are highly immunogenic for both humoral and cell-mediated responses after a single dose, can be produced in a highly efficient manufacturing process and can be thermostabilised. Efficacy in livestock against Rift Valley Fever virus and safety in humans in a number of different vaccine programmes has been demonstrated. A ChAdOx1 CCHF vaccine has been produced and is immunogenic in mice. We now propose to conduct a more detailed immunogenicity study and then test vaccine efficacy of one and two dose vaccine regimens against lethal challenge in a mouse model. Data generated in this study will support an application for the next stage of the development process which will be to demonstrate vaccine immunogencity and efficacy in sheep in a CCHF-endemic area.