Risk factors associated with porcine leptospirosis in Uttar Pradesh, India.

Abstract

Porcine leptospirosis is a zoonotic disease. Pigs act as reservoir host for various Leptospira serovars. A study aimed to pinpoint the risk factors of porcine leptospirosis was designed on pigs of three agro-climatic zones- Midwestern plain zone (Bareilly), Eastern Plain zone (Barabanki) and Southwestern semi- arid zone (Aligarh) of Uttar Pradesh. Risk factor analysis was done using pretested structured questionnaire. The univariate analysis of the variables of interest was done using Fisher’s exact test/ Pearson’s chi-square. Further, multivariate analysis was done through logistic regression model using serological status of animal in Microscopic Agglutination Test (MAT) as dependent variable. The overall seropositivity of 23.81% (70/294; 95% CI: 18.94% - 28.67%) was recorded in MAT with Icterohaemorrhagiae as the leading serovar. Multivariate risk factor analysis revealed that accessibility of swine to unsanitary wallowing ponds (Odds ratio: 8.58; 95% CI: 3.34-21.93; P<0.001), contact of domesticated pigs with wild/feral pigs and water buffaloes (Odds ratio: 12.83; 95% CI: 3.72-44.26; P<0.001) and accessibility of swine to garbage pits (Odds ratio: 3.97; 95% CI: 1.28-12.26; P<0.016) were statistically significant. Further, risk factor analysis revealed that mature pigs of >2 years age had higher chance of contracting leptospirosis than young pigs of <2 years (Odds ratio: 12.09; 95% CI: 2.92-50.03; P<0.001) owing to higher probability for exposure to above mentioned risk factors. Domesticated pigs reared under mixed farming system that gets access to wallow in unsanitary ponds frequented by feral pigs and water buffaloes and pigs that access garbage pits frequented by rodents were at high risk of contracting leptospirosis.