PREPARATION OF INACTIVATED FREEZE-DRIED RVF VACCINE

Document Type : Original Article

Authors

Veterinary Serum and Vaccine Research Institute, Agricultural Research Centre, Ministry of Agriculture, Dokki, Giza, Egypt

Abstract

Attentions were directed to develop a lyophilized inactivated RVF vaccine to overcome the disadvantages associated with the poor keep‌ing quality, as well as the short immunizing antibody titre of the conven‌tionally produced RVF liquid-inactivated vaccine. The used virus seed having an initial titre of 107 TC1D50 was inac‌tivated by 0.1M binary ethyleneimine (BEI) at a concentration of 1 %. Full inactivation of the virus was achieved after incubating the mixture at 37`C for 6 hours. Tetanus toxoid was added at 3 different concentrations, then, an equal volume of stabilizer was also added to the inactivated virus. The vaccine was dispensed into 2m1 vials and freeze-dried. The safety and potency in mice showed that RVF vaccine com‌bined to tetanus toxoid 200 limit of flocculation (L.F.) concentration is absolutely safe and potent. So, this innovated lyophilized RVF vaccine combined to tetanus toxoid will solve the disadvantages of the already produced liquid RVF vaccine besides the prophylactic measures of tetanus.