Seroprevalence of Trichinella in slaughter pigs in Kathmandu Valley, Nepal.

The aim of the present study was to determine the Trichinella seroprevalence in slaughter pigs in Kathmandu Valley, Nepal. Serum samples were obtained from 400 pigs at 4 major slaughterhouses and tested for Trichinella antibodies by ELISA using larval excretory-secretory (E/S) antigen. Four were positive and one was equivocal, giving a Trichinella seroprevalence of 1% (95% CI: 0.27 - 2.54). On titration, all positive and equivocal samples had titers greater than 1:80. Upon re-examination the equivocal sample failed to give a positive ELISA result. The pigs were from four major areas of Nepal, Kathmandu Valley, eastern Nepal, Terai and adjoining areas of the valley. Positive results were found from only Kathmandu Valley and adjoining areas. There was no significant difference in the prevalence between areas (p = 0.43). All four positive samples were from indoor managed pigs. The Trichinella seroprevalence determined in this study deserves a direct demonstration of the parasites for proof of the presence of Trichinella in Nepal and to discover the species and infection sources.