Outbreak Investigation, Isolation, and Molecular Characterization of Lumpy Skin Disease Virus in Cattle from North West Oromia Region, Ethiopia.

Abstract

Lumpy skin disease (LSD) is an economically significant viral disease because of its high morbidity and high production loss. Vaccination of cattle using LSD vaccines is a more effective disease preventive and control strategy in endemic countries such as Ethiopia. Despite high vaccination coverage, there is an increasing number of field reports of the disease outbreaks. Thus, an observational study was designed to investigate disease, characterize the disease-causing agent, and isolate the virus from a local isolate for future vaccine development. Wera Jarso and Amuru districts in North West Oromia were chosen based on outbreak occurrence. For this study skin, 13 pooled biopsy samples were collected from affected cattle. In this outbreak investigation, the morbidity rate was 6.50%, the mortality rate was 0.50%, and the case fatality rate was 7.77%. The virus was isolated from all skin samples on both lamb testis and lamb kidney primary cells and confirmed to be LSDV using conventional and real-time PCR genotyping. Therefore, after each suspected LSD outbreak, a molecular test should be carried out to confirm the cause of the disease, targeting the previously suggested RPO30 or GPCR genes. Further studies targeting more regions and outbreaks, including full genome sequencing to check for genetic differences between the field viruses and vaccine strains, are recommended.