First serological and molecular detection of Toxoplasma gondii in guinea pigs (Cavia porcellus) used for human consumption in Nariño, Colombia, South America

Authors: LOPEZ-OROZCO, NATALIA - Universidad Technologica De Pereira; QUIROZ-BUCHELI, ADRIANA - Collaborator; Kwok, Oliver; Dubey, Jitender; CANON-FRANCO, WILLIAM - Universidad De Caldas; SEPULVEDA-ARIAS, JUAN - Universidad Technologica De Pereira

Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/23/2022
Publication Date: 10/29/2022
Citation: Lopez-Orozco, N., Quiroz-Bucheli, A., Kwok, O.C., Dubey, J.P., Canon-Franco, W., Sepulveda-Arias, J. 2022. First serological and molecular detection of Toxoplasma gondii in guinea pigs (Cavia porcellus) used for human consumption in Nariño, Colombia, South America. Veterinary Parasitology. 36. Article e10081. https://doi.org/10.1016/j.vprsr.2022.100801.
DOI: https://doi.org/10.1016/j.vprsr.2022.100801

Interpretive Summary: Food safety is a worldwide concern. Among these zoonotic pathogens, the single celled parasite Toxoplasma gondii is perhaps the most ubiquitous, having been identified in virtually all warm- blooded animals and humans. Toxoplasma gondii can cause serious illness in humans and animals, including birth defects. Humans become infected postnatally by eating undercooked meat infected with T. gondii tissue cysts or by ingesting oocysts from the environment. Cats (domestic and wild) are the main reservoir of infection because they are the only hosts that can excrete the environmentally resistant stage, the oocyst. Rodents are important in the life cycle and epidemiology of T. gondii because they serve as sources of infection for cats, as sentinel animals for environmental contamination, as models of infection for the biological study of T. gondii and, some species of rodents serve as food for humans. Guineapigs are commonly raised for human consumption in Colombia and several other countries. Here, the authors report first documentation of Toxoplasma infection in guinea pigs from Nariño, Colombia, South America. This research was completed in 2017, before the redirection of Toxoplasma research at USDA.

Technical Abstract: Consumption of undercooked meat from different animal species is one of the main routes of transmission for Toxoplasma gondii worldwide. In the South American Andes, the guinea pig (Cavia porcellus) is a domestic rodent that represents one of the main sources of animal protein for indigenous communities. However, the prevalence of infectious agents such as T. gondii in this species is still unknown. Our study conducted in guinea pigs that were bred in traditional systems located in the village of José María Hernández (Nariño, Colombia) revealed the presence of anti-T. gondii antibodies in 32.4% of the animals evaluated (22 out of 68 guinea pigs), with a cutoff point of 25 for the modified direct agglutination test (MAT). Conventional PCR detection of the T. gondii-specific RE fragment (529 bp) in 204 collected tissues revealed the presence of T. gondii DNA in several organs, such as the brain (16/68), muscle (11/68), and heart (4/68), with an overall molecular detection frequency of 26.5% (18 out of 68 guinea pigs). This is the first report confirming the natural infection of guinea pigs (C. porcellus) with T. gondii, demonstrating their potential epidemiological role in transmitting the infection to autochthonous populations.