Seasonal Rhythmicity of Contagious Ecthyma in Small Ruminants

Small ruminant species including ovine and caprine species are vulnerable to seasonal and periodic rhythmicity of many pathogenic organisms or diseases. However, such a study on contagious ecthyma was lacking until recently we explored the seasonal and periodic occurrence of this important contagious and zoonotic disease affecting sheep, goats and many other species of wild ruminants. Outbreaks (N=12) of contagious ecthyma were investigated from ovine and caprine species during November, 2016 to May, 2017. Descriptive epidemiology was studied with respect to various host- and environment- related factors. Seasonal occurrence was more in spring (29.33 %) compared to winter (3.05 %). Time-related occurrence of the disease revealed maximum number of cases in April ( 56.1 %) and minimum during February (2.0 %). Age related occurrence showed that lambs and kids of < 3 months of age were more affected compared to > 3 month old animals (74.9 % versus 25.1 %). Variation in spatial distribution was noted when the other host-pathogen-environment factors did not differ significantly (P>0.05). The overall morbidity, mortality and case-fatality rates observed were 7.23 %, 0.42 % and 5.8 % respectively. From this study it can be inferred that contagious ecthyma has seasonal and periodic rhythmicity in ovine and caprine species.