Long term immunity in African cattle vaccinated with a recombinant capripox-rinderpest virus vaccine

Cattle were vaccinated with a recombinant capripox-rinderpest vaccine designed to protect cattle from infection with either rinderpest virus (RPV) or lumpy skin disease virus (LSDV). Vaccination did not induce any adverse clinical responses or show evidence of transmission of the vaccine virus to in-contact control animals. Approximately 50% of the cattle were solidly protected from challenge with a lethal dose of virulent RPV 2 years after vaccination while at 3 years approx. 30% were fully protected. In the case of LSDV, all of 4 vaccinated cattle challenged with virulent LSDV at 2 years were completely protected from clinical disease while 2 of 5 vaccinated cattle were completely protected at 3 years. The recombinant vaccine showed no loss of potency when stored lyophylized at 4 degrees C for up to 1 year. These results indicate that capripoxvirus is a suitable vector for the development of safe, effective and stable recombinant vaccines for cattle.