Background: Rift Valley Fever (RVF) and Pest des Petits Ruminants (PPR) are two viral diseases that pose a significant threat to sheep populations, leading to substantial financial losses.
Methods: The current study aimed to make a vaccine that contains both the inactivated RVF and the live attenuated PPR viruses in a freeze-dried form. This vaccine aimed to provide sheep with protection against both diseases with a single injection. It was made with the ZH501 strain of the RVF virus, which has a titer of 10^7.5 TCID₅₀/ml, and the Nigerian PPR virus (N75/1), which was grown on the VERO cell line. The vaccine underwent quality control assessments. To make a lyophilized vaccine, inactivated RVF and attenuated PPR viruses were mixed and stabilizers of 1% and 0.5% carbomers were added.
Results: Evidence has shown that the vaccine was secure and free from foreign impurities such as mycoplasma, fungus, and anaerobic and aerobic bacteria. Furthermore, it does not have any detrimental consequences for unvaccinated sheep in close proximity. The vaccine demonstrated efficacy for over 6 months since the vaccine formulated with 0.5% carbomer established a sufficient level of protective immunity prior to the administration of the vaccine formulated with 1% carbomer.
Conclusion: It is advisable to utilize the vaccine containing 0.5% carbomer as a stabilizer, as it has been shown to rapidly achieve a protective level against both diseases. This approach allows for the administration of a single immunization, thereby saving time, effort, and money.