Ascorbic acid is an important antioxidant. However, in the presence of transition metals such as Copper sulphate, it also has pro-oxidant capabilities. This work investigates the effect of ascorbate Cu+2 in the infectivity of Rift Valley Fever virus (RVFV) as an inactivator. RVFV was treated with different concentrations (0.5, 1.0, 1.5 mg/ml) of Ascorbic Acid in the presence of Cu+2Micro-titer technique and mice assay were used to titrate the used virus, toxicity of Ascorbic Acid and also determination of inactivation kinetics of RVFV.The results revealed that RVFV was completely inactivated within 24 hours post treatment with 1.0 mg and 1.5 mg/ml of Ascorbic Acid compared with the control group, and the potency test of the
experimental batch of A.A inactivated RVFV vaccine had ED500.014 in immunized mice, concluded that ascorbic acid can be used as an inactivator agent for preparation of safe and potent RVF inactivated vaccine.