..::Veterinary Serum and Vaccine Research Institute::..

Proc. Thel st Intern. Conf. Vet. Res. Div., NRC, Cairo , Egypt , February 15-17 th 2004

Trials for production of a combined living attenuated
sheep pox and Rift Valley fever vaccine

M.M. Taha; S.S. Samir; Iman M.S. Shalakamy and A.M.Daoud

Veterinary Serum and Vaccine Research Institute, Abbassia, Cairo.

Summary

	Several formulae containing sheep pox (SP) vaccine (10 5.5 and 10 4.5 TCID 50 /ml) and attenuated Rift Valley fever (RVF) vaccine (10 7.5 , 10 5.5 TCID 50 ml ), were prepared and lyophilized together with lactabumin sucrose stabilizer. The different combined formulae were tested for sterility, safety against RVF in mice and lambs; while the safety and efficacy against SP were applied in susceptible lambs. On the other hand, the potency of the prepred vaccine was tested and proved that the types.

	1,4,5 and 6 gave acceptable PD 50 (< 0.02/ml ) for RVF in adult mice, as well, the potency of the types 1 and 6 representing the highest and the lowest dilutions of RVF vaccine (10 7.5 and 10 5.5 TCID 50 ml) with the 2 dilutions of SP vaccine (10 5.5 and 1 04 .5 TCID 50 ml), was tested in susceptible lambs and recorded a protective difference of log titer (> log10 2.5 ).

	The obtained results stated that the prepared combined SP vaccine and attenuated RVF vaccine proved to be sterile, safe, potent and efficient for vaccination against RVF and SP diseases. Confimatory specific serological test ( serum neutralization test ) was carried out on the sera of vaccinated sheep with combined vaccine, it recorded protective neutralizing indices for SP and RVF (> 1.5 and > 1.7 respectively) 21 days post vaccination.