Lumpy skin disease: economic impact and field vaccine efficiency evaluation in Zebu cattle population in selected districts of the Gamo Zone, Southern, Ethiopia

Abstract

Lumpy skin disease (LSD) is a serious pox disease of cattle that is antigenically related to sheep pox and goat pox viruses. In Ethiopia, LSD is primarily controlled through vaccination of cattle with the Kenyan sheep pox vaccine (KS1-O180 vaccine strain). However, recurring outbreaks among vaccinated cattle have been widely reported. Therefore, this study combined a two-year retrospective survey (February 2019–January 2021) involving 246 herd owners with a ten-month prospective follow-up study involving 446 cattle (February–November 2022) in selected districts of Gamo Zone, Southern Ethiopia. Clinical cases were confirmed by real-time PCR analysis of skin nodule samples. All data were analyzed using STATA version 16. and descriptive Statistics were used to summarize the findings. The findings showed that the mean annual economic loss due to LSD was USD 29.49 per households, mainly attributable to animal deaths (USD 17.85), milk losses (USD 1.4), labor replacement (USD 4.8), ox replacement (USD 4.15), and treatment costs (USD 1.29). The morbidity rate was 20.3% at the household level and 4.74% at the animal level, while mortality reached 7.7% and 1.63%, respectively. Sex was significantly association with LSD infection ( P < 0.05), with males cattle being more affected than females. Moreover, prospective follow up study showed that 3.14% of vaccinated cattle developed LSD, which was confirmed by real time PCR. LSD poses a great socio-economic impact and its occurrence in the vaccinated cattle indicates the need to incorporate vaccine strains that provide better protection than the currently used KS1-O180 vaccine strain and to strengthen awareness among livestock owners regarding disease prevention, mitigation and control strategies besides regular vaccination programs.