Abstract:
Lumpy skin disease and Rift Valley fever are two high-priority livestock diseases which
have the potential to spread into previously free regions through animalmovement and/or
vectors, as well as intentional release by bioterrorists. Since the distribution range of
both diseases is similar in Africa, it makes sense to use a bivalent vaccine to control
them. This may lead to the more consistent and sustainable use of vaccination against
Rift Valley fever through a more cost-effective vaccine. In this study, a recombinant
lumpy skin disease virus was constructed in which the thymidine kinase gene was
used as the insertion site for the Gn and Gc protective glycoprotein genes of Rift Valley
fever virus using homologous recombination. Selection markers, the enhanced green
fluorescent protein and Escherichia coli guanidine phosphoribosyl transferase (gpt), were
used for selection of recombinant virus and in amanner enabling a second recombination
event to occur upon removal of the gpt selection-pressure allowing the removal of both
marker genes in the final product. This recombinant virus, LSD-RVF.mf, was selected
to homogeneity, characterized and evaluated in cattle as a vaccine to show protection
against both lumpy skin disease and Rift Valley fever in cattle. The results demonstrate
that the LSD-RVF.mf is safe, immunogenic and can protect cattle against both diseases.
