Spatial seroprevalence of classical swine fever in India.

Classical swine fever (CSF) is a highly contagious dreadful disease of pigs leading to 100% mortality in acute form in susceptible population thereby causing huge economic loss to pig farmers. This study was undertaken to assess the seroprevalence of CSF at national level. A two-stage random sampling methodology was adopted that included 271 villages from 115 districts of India. A total of 5848 pig serum samples from twenty-five states and one Union Territory of India were collected during 2018-2019. A percent positivity of 38.52 was found at national level. Puducherry and Sikkim showed the highest and lowest percent positivity respectively. Pigs from the west zone showed the highest seroprevalence of 55.83% and those from the south zone showed the lowest of 30.25%. Adult pigs in the north and east zones showed highest percent positivity of 81.8, whereas pigs of more than 3 years of age showed highest percent positivity of 54.9, 75 and 62.5 in the north east, west and central zones respectively. Young ones showed percent positivity of 41.5 in the south zone. Higher rainfall (> 3 mm/day) and lower temperature (< 26 °C) favoured the existence of disease in the north east region combined with high density of pig population. Amidst no fool proof alert system, seroprevalence is the best method to assess the status of CSF in herd/population that provides the policymakers to plan for control of disease.