Development of threshold levels of climate variables for incidence of livestock diseases

Spatio-temporal epidemiological (outbreaks, diagnosed cases and death cases) data (2002-14) analysis of eight livestock diseases in Tamil Nadu state revealed Anthrax (109) was high followed by Foot and mouth disease [FMD] (99), Peste des petits ruminants [PPR] (45), Bluetongue [BT] (44), Black quarter [BQ] (34), Haemorrhagic septicemia [HS] (15), Sheep and Goat pox (15) and Enterotoxaemia [ET] (9). Season wise analysis revealed highest number of outbreaks during north east monsoon season for all the diseases. Agroclimatic zone and cluster analyses revealed that highest number of outbreaks occurred in north eastern and southern zones. Bio-climatograph analysis showed relationship between rainfall and livestock disease outbreaks for all the diseases. Disease prevalence seemed to be higher in north eastern and southern zone of Tamil Nadu and during northeast monsoon. Preventive vaccinations against anthrax, FMD, PPR have to be initiated in the two zones before monsoon to mitigate the livestock diseases.


Disease risk maps for Karnataka and Tamil Nadu were prepared using the variables like livestock population, rainfall, NDVI and LST. The risk map analysis of PPR indicated that the intensity of the PPR outbreaks decreased by six times in Karnataka possibly due to the effective PPR control programme (vaccination) implemented in Karnataka. There is extension of geographical area of occurrence of PPR in Karnataka. It is likely that due to the vaccination programme, the herd immunity is high and the pathogen is trying to find the hosts for spread of disease. Hence, there is extension of the PPR risk areas in Karnataka during 2011-15 period with decreased risk intensity.

Temporal trends in spread and intensity of PPR in Karnataka