Interferon a/b receptor deficient (IFNAR -/-) mice were previously found to be susceptible to the live attenuated vaccine strain of Rift Valley fever virus (RVFV) MP12 , providing a BSL-2 model to study RVFV. Female IFNAR -/- mice, 6-8 weeks of age, are challenged by intraperitoneal injection. Death is rapid, with 100% mortality observed at day 3 with 10^4 pfu and by Day 4 with 10^3 pfu. Animals develop symptoms that are reflective of severe human disease including high viral titers in the liver. Common readouts for this model include weight, survival, health observations, serum and organ titers, and cytokine analysis.
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