Molecular detection and genotype identification of Toxoplasma gondii in domestic and industrial eggs

Birds are important intermediated hosts of Toxoplasma gondii. Consumption of chicken meat and its infected products is one of the main sources of human infection with T. gondii. However, little information is available about T. gondii infection in egg. In this study, the contamination of industrial and local eggs with Toxoplasma was investigated by PCR method targeting the RE gene in two tropical cities of Iran. Genotypes of T. gondii were determined by PCR-RFLP method targeting the SAG3 gene. T. gondii DNA was detected in 11% (22/200) of the eggs. Genotyping of 14 T. gondii isolates revealed that all of the isolates were belonged to genotype III of T. gondii. Sequencing of the isolates by the SAG3 gene showed 95%–100% similarity with the T. gondii isolates in GenBank. Practical applications: The findings of this study suggested that consumption of raw or undercooked eggs might play a role in human infection with Toxoplasma. Hence, consumption of adequately cooked eggs should be considered for prevention of human toxoplasmosis