Toxoplasma gondii in meat products for human consumption

MONTIEL B*, CRICRI JP*, SANCHEZ VR, RUYBAL P, MARTIN V, MORETTA R

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2019

Toxoplasma gondii is an intracellular protozoan with a worldwide prevalence in human and animal populations. T. gondii is capable of infecting a wide range of warm-blooded animals that include birds and mammals. In infected (non-feline) animals, the parasite forms resistance structures called cysts, which may be present in different tissues including muscle. Since each cyst can contain 10 to 1000 parasites, the consumption of meat without proper cooking or the handling of raw meat itself constitutes an important route of infection.The aim of this study was to conduct a small scale survey in which we assessed the presence and viability of T. gondii in meat samples for human consumption. To determine the prevalence of this infection, 18 pork meat products were acquired in retail stores from 11 localities of Buenos Aires City and surrounding areas. The presence of the parasite was confirmed by hemi-nested PCR for 12 out of 18 samples. To evaluate T. gondii viability, pepsin digested pork material was inoculated in mice (2-3 per sample). Thirty days after inoculation, the animals were euthanized and serum, brain, liver and heart samples were collected.A total of 10 mice were positive for antibodies against T. gondii, measured by indirect ELISA, representing 8 meat samples. On the other hand, molecular detection in DNA extracted from mouse brains showed that the parasite was present and viable in 9 meat samples. Additionally, in order to detect possible variations in T. gondii tropism, we analyzed liver and heart samples by hemi-nested PCR. We confirmed the presence of the parasite in both organs in 7 meat samples.Altogether these results confirmed the presence and viability of the parasite in 50% of the total samples.Future experiments will be focused on the characterization of T. gondii strain genotypes to gain insight into the distribution and variability of the parasite in meat products.