Descriptive Epidemiology of the first outbreak of Lumpy Skin Disease in cattle in Indonesia

Abstract

Abstract This study describes the first outbreak of Lumpy Skin Disease (LSD) in cattle in the Bengkalis region, Indonesia and vaccination to control the epidemic. Data on the outbreak and vaccination was obtained from the local veterinary authority of the Bengkalis region, Indonesia. Climatological data was provided by the Meteorological, Climatological, and Geophysical Agency of Riau Province. Over the 5.5 months period, the outbreak caused 10.4% (94/906) morbidity and 0.6% (6/906) mortality of cattle on infected farms. Temporally, three epidemic waves occurred during the outbreak period. Villages with cattle populations of >150 animals (n=36) were 5.3 times more likely to be infected with LSD compared to villages with smaller cattle populations (n=107) (CI: 2.56 – 10.90, P<0.01). The vaccination campaign covered 43.8% of cattle in villages within a 10 km radius of cases. However, vaccination in villages with larger cattle populations (n=29) was 0.63 less likely to cover 50% of the cattle populations compared to villages with smaller cattle populations (n=41) (CI: 0.39 – 1.02, P=0.05). By the time the first two and the major waves ceased, vaccination had covered only 0.0% (n=6036), 27.8% (n=6,036) and 8.4% (n=6,556) of the cattle in the 10 km radius of the respective waves. The outbreak was statistically associated with rainfall and its interaction with temperature (F(2, 13)=5.822, R2=0.47, P=0.016). This study indicates that the LSD outbreak had low morbidity and mortality. Despite the low vaccination rate, the outbreak ceased, possibly due to plummeting of the abundance of insect vectors.