Detection of Trichinella britovi in pork sausage suspected to be implicated in a human outbreak in Mendoza, Argentina

Abstract

Of the three Trichinella species described in South America, T. spiralis, T. pseudospiralis and T. patagoniensis, only the former has been implicated in human infections from consumption of pork-derived products. During a presumed trichinellosis outbreak in 2012 in Mendoza, Argentina, we evaluated the serological responses of three patients who had eaten the incriminated food and had signs and symptoms compatible with trichinellosis, using ELISA. We also analyzed potentially contaminated pork sausage by artificial digestion technique and recovered Trichinella muscle larvae, which were identified to the species level using a PCR multiplex assay and by sequencing a region of the mitochondrial gene coding cytochrome oxidase subunit I. No antibodies were detected in the sera of the patients, probably because the samples were collected during the immunological window period. According to molecular identification, all larvae from the sausage corresponded to T. britovi. Trichinella britovi is reported here for the first time in the American Continent, and represents the only cold-tolerant member of the genus in the Neotropics. This species was most likely introduced from Europe to South America during Spanish colonization through pigs, wild boars and/or rats.