Seroprevalence of Toxoplasma gondii infection among veterinary staff in Ontario, Canada (2002): Implications for teratogenic risk

Veterinary staff attending the 2002 Annual Ontario Veterinary Medical Association Conference were invited to discuss their toxoplasma seroprevalence. Interested attendees completed a questionnaire and a physician drew blood samples to determine T. gondii titres using the ELISA IgG test.We collected 161 completed questionnaires, and 141 blood samples. There were 20 (14.2%, CI95%:8.4–19.9%) reactive titres among the veterinarian staff (80% females aged 30–45). All were regularly exposed to cats, washed their hands when in contact and few wore gloves routinely.These findings of low positive rates may be used to reassure veterinary staff that their exposure to cats does not appear to increase their risk of contracting toxoplasma infection and that pregnant women are not at an increased risk by owning a cat.The incidence of toxoplasmosis varies around the world, with the highest rates in Europe (up to 55% in France). [1] The parasite can be transmitted to humans in several ways, including ingestion of raw or undercooked meat, contact with soil, eating poorly washed raw fruits and vegetables, and ingestion of oocysts in cat faeces. [2] An investigation of a recent Canadian outbreak has suggested that Toxoplasma gondii could also be waterborne.[3]The most recent and reliable estimate of the seroprevalence of antibodies to Toxoplasma gondii in the United States was provided by the third National Health and and Nutrition Examination Survey (NHANES-III), a study of a representative sample of the non-institutionalized population. [4] The antibody tests for toxoplasma were conducted during 1991–1994, with the survey design comprised of a cluster sample of US residents. Serum samples from 17,658 people were tested at the Centers for Disease Control and Prevention (CDC) for Toxoplasma-specific IgG antibodies; 23% were positive. Of 5,988 women of childbearing age (i.e., age 12–49 years), 14% were seropositive.There is no comparable statistic for Canada, but it would be reasonable