Low levels of Trichinella spp. antibodies detected in domestic pigs at selected slaughterhouses with farm-based exposure assessment in Bulacan, Philippines

Abstract

Trichinella spp. is considered as one of the most widespread food-borne zoonotic parasites globally. The disease it causes impacts human public health, pig production, and food safety. Unfortunately in the Philippines, there is still insufficient research on the presence of Trichinella among livestock. This study aims to update its status and records in the country, by verifying the presence of Trichinella spp. IgG antibodies from the selected province, Bulacan, and link its potential presence to known animal husbandry and farm practices. This study was conducted in purposively selected slaughterhouses. Pigs were randomly selected for each slaughterhouse. Blood samples were collected and serum samples were harvested from each pig samples (n = 555). Sera were tested using ELISA for the detection of Trichinella spp. IgG antibodies. For serologically positive pigs, farm-based exposure assessment was conducted to evaluate potential routes of infection. For this study, a total of 555 blood sera, wherein three blood sera were detected to be serologically positive (low prevalence of 0.54 %, 95 % CI = 0.11-1.57). Potential infection routes point towards outdoor housing management, pigs with unknown origin, pig farms presence with rodents, and pigs fed with waste as important risks. In summary, the present paper confirms that Trichinella spp. antibodies were detected in very low prevalence in Bulacan, Philippines and demonstrated the potential utilization of antibody detection as an efficient and complementary early screening tool in Trichinella detection among pigs without immediately sacrificing livestock for the sake of testing. These results merit calls for a wider screening, testing, and isolation of Trichinella spp. in pigs from other Philippine provinces.

Keywords: Indirect ELISA; Livestock; Trichinella spp.; Trichinellosis.