Serological and molecular detection of Toxoplasma gondii among slaughtered domestic ruminants and pregnant women in Gondar town, Northwest Ethiopia

Abstract

Toxoplasma gondii is a global zoonotic cyst forming intracellular protozoan parasite which affects almost all warm-blooded animals including humans. Humans mainly get this infection by ingested improperly cooked or raw meat consisting of viable tissue cysts or by contaminated foods and water within sporulated oocysts or through the placenta. It causes abortion and stillborn in small ruminants and pregnant women. There is no confirming study report for the existence of this parasite among food animals in Ethiopia, especially in the study area. Thus, this study aimed to detect Toxoplasma gondii among slaughtered domestic ruminants and pregnant women using serologically and molecularly at Gondar town, Northwest Ethiopia. A cross-sectional study was conducted from September 2019 to October 2020 by collecting a total of 200 blood and matching tissue samples from purposively selected domestic ruminants and pregnant women. Latex agglutination test and nested polymerase chain reaction were used for the detections of this infection in the study subjects. Univariate logistic regression was also used to determine the association of risk factors with Toxoplasma gondii occurrence. The overall serological, first polymerase chain reaction and nested polymerase chain reaction findings of this study were 60%, 22.7% and 11.3% in slaughtered animals and 46%, 24% and 18% in pregnant women, respectively. Moreover, 62%, 58.7% and 60% of latex agglutination tests; 34%, 24% and 10% of first polymerase chain reaction and 20%, 14% and 0% with nested polymerase chain reaction were also found in sheep, goats and cattle, respectively. Significant associations were observed between Toxoplasma gondii seropositivity and the age of sheep (OR: 5.368; P: 0.044) and sex with goats (OR: 4.091; P: 0.022). Seropositivity of Toxoplasma gondii antibodies were also significantly influenced by raw meat (OR: 5.250; P: 0.036) and milk (OR: 0.263; P: 0.041) consuming habits of the study participants. Moreover, there were also fair concordant between latex agglutination and first polymerase chain reaction tests on slaughtered animals (Kappa: 0.207) and pregnant women (Kappa: 0.290). Generally, these comparative tests confirmed the existence of this infection in animals that played up a pool of public health risks in human consumers, particularly pregnant women. Thus, thoroughly cooking raw meats and pasteurized raw milk will be the best prevention and control strategies of this infection in animals and humans. Further works on its genotyping of this pathogen will be also convinced.