Purpose: This study aimed to determine the seroprevalence and correlates of Leptospira IgG antibodies in backyard pigs in the northern Mexican state of Durango. We performed a cross-sectional study of 305 backyard pigs. Anti- Leptospira IgG antibodies were detected using microscopic agglutination assay (MAT) with a panel of 12 Leptospira antigens.
Results: Overall, antibodies against Leptospira (any of the 12 Leptospira serovars examined) were found in 186 (61.0%) of the 305 pigs studied. Seropositive pigs were found on 80 (70.2%) of the 114 properties surveyed. The predominant serovar was Leptospira interrogans Pomona ( n = 55); followed by Leptospira noguchii Lousiana and Leptospira santarosai Tarassovi ( n = 53 each); L. interrogans Bataviae ( n = 47); Leptospira biflexa Semaranga and L. interrogans Hebdomadis ( n = 36 each); L. interrogans Pyrogenes ( n = 30); L. interrogans Djasiman ( n = 20); Leptospira borgpetersenii Ballum ( n = 11); L. noguchii Panama and L. interrogans Canicola ( n = 5 each); and L. borgpetersenii Mini ( n = 2). Logistic regression showed that seropositivity was associated with low (<1000 m above sea level) altitude (odds ratio [OR] = 3.24; 95% confidence interval [CI]: 2.01–5.20; P < 0.001).
Conclusions: This is the first report of Leptospira exposure in backyard pigs in Mexico and of an association between Leptospira exposure in pigs and altitude. Backyard pigs represent a high-risk group for Leptospira exposure.