Toxoplasma gondii in sheep and goat livers: Risks for human consumption

Abstract

Toxoplasmosis is one of the most important zoonotic diseases worldwide and is caused by the protozoan Toxoplasma gondii. Besides vertical transmission during pregnancy, humans can become infected post-natally either by oral uptake of sporulated Toxoplasma oocysts or through ingestion of tissue cysts upon consumption of raw or undercooked meat. The aim of this study was to approximate the risk of human infection via liver consumption by estimating the seroprevalence and molecular prevalence of T. gondii in slaughtered sheep and goats in Iran. In the present study, livers from 150 sheep and 150 goats were collected at slaughter. In- house enzyme-linked immunosorbent assay was performed in T. gondii liver juice. Parasite-specific polymerase chain reaction was carried out on all samples obtained from liver tissues. Antibodies against T. gondii were detected by in-house ELISA in 32.6% sheep and 48% goat livers and 8% and 11.3% of sheep and goat livers were positive for the presence of T. gondii DNA, respectively. The results of this study provide baseline information on the presence of T. gondii in sheep and goats livers and imply an important human health and hygienic risk associated with the consumption of raw or undercooked liver from these animal species.

Seroprevalence and Risk Factors of Toxoplasma gondii in Ruminant Meats from Wet Markets in Klang Valley and Abattoirs in Selangor, Malaysia

“…The current prevalence of T. gondii antibodies found in meats of goats (42.5%) and sheep (35%) from the two abattoirs is similar to that reported in Iran (goats; 48%, sheep; 32.6%) [24] and Pakistan (goats; 42.8%, sheep; 26.2%) [25]. However, the prevalence estimate in the present work is higher than that reported in goats in Myanmar (11.4%) [26], and lower than the estimates in Egypt (62%) [8] and Italy (63.3%) [27].…”

Molecular and serological detection and of Toxoplasma gondii in small ruminants of southwest Iran and the potential risks for consumers

“…The sample size was calculated by the statistical formula presented by Naing et al ( 2006 ). The prevalence estimation was made based on the previous article that had reported the prevalence of T. gondii in sheep (serology: 32.6% and PCR: 8%) and goats (serology: 48% and PCR: 11.3%) in Iran (Bahrami et al 2019 ). For the purpose of this study, a slaughterhouse in the southwestern part of Iran (Ahvaz, Khuzestan province) was visited eight times, once a week during autumn 2018, by the researchers to collect blood samples from the common carotid arteries of a total of 150 sheep and 150 goats using a 10-mL vacutainer tube immediately after bleeding.…”

“…Blood sera were tested for the presence of anti- T. gondii IgG antibodies, using an in-house ELISA in flat-bottom 96-well microplates as previously described (Bahrami et al 2019 ).…”

“…For example, a considerable risk factor of toxoplasmosis in Iran is the consumption of raw or semi-cooked liver of warm-blooded animals such as sheep and goats as a treatment for iron deficiency, especially by pregnant women, deeming to be nourishing in cases of pregnancy or general lethargy mainly due to some traditional beliefs. This consumption pattern may result in toxoplasmosis disease (Hajimohammadi et al 2017 ; Bahrami et al 2019 ).…”

“…Toxoplasmosis is conventionally diagnosed by parasite isolation from biopsy material, which is not cost-effective and timesaving for large scale detection of the parasite, usually taking 6 weeks to detect parasitic DNA in the animal tissues. Accordingly, molecular and serological methods have been suggested to substitute the earlier detection techniques (Bahrami et al 2019 ; Liu et al 2015 ).…”