Chikungunya virus (CHIKV) is a mosquito-borne alphavirus endemic in Africa and Asia that causes a debilitating disease in over 2 million people every year in explosive outbreaks. There are currently no vaccines or therapeutics available for this emerging virus. IBT Bioservices has established a lethal model for this disease based on the model published by Partidos et al, Probing the attenuation and protective efficacy of a candidate Chikungunya virus vaccine in mice with compromised interferon (IFN) signaling, (Vaccine, 2011: 3067-73).

The model utilizes AG129 mice deficient in IFNa/B and IFNg signaling as well as an attenuated strain of CHIKV (181/25). This model is ideal for testing antiviral drugs and CHIKV vaccine candidates and has the following advantages:

• Lethal challenge dose established allowing efficacy testing using morbidity and mortality endpoints.
• The virus causes necrotic histopathological changes in the spleens of infected mice.
• The model utilizes an attenuated strain (CHIKV 181/25) that is safe to handle in biosafety level 2 (BSL-2) environment thus avoiding high costs of performing BSL-3 studies.
• The model has been successfully used to demonstrate efficacy of CHIKV experimental vaccine candidates.
• Adoptive transfer of hyperimmune serum in this model protects against lethal challenge suggesting the utility of the model for evaluation of therapeutic candidates.