Toxoplasma Working Group

Estimating the incidence of toxoplasmosis and cytomegalovirus infection in pregnant women

Project Lead: Nicolas Gilbert, Public Health Agency of Canada
Infections with cytomegalovirus and with the coccidian protozoa Toxoplasma gondii during pregnancy can be transmitted vertically to the fetus and cause congenital anomalies. However, little is known about the susceptibility of Canadian women of reproductive age to these infections, or about infection or seroconversion rates in pregnant women. Our limited knowledge arises from dated studies of specific occupational groups or from specific geographic areas and does not provide adequate information on the disease risk of these infections in either the pregnant population or the adult female population in Canada today.

The overall objective of this study is to estimate the incidence of toxoplasmosis and CMV infection in a cohort of pregnant women. Specific objectives are:
  • To estimate the seroprevalence of Toxoplasma and CMV antibodies in pregnant women
  • To determine the incidence of Toxoplasma and CMV infections (seroconversion) during pregnancy
  • To identify risk factors associated with existing and acquired CMV infection in pregnant women

This study uses biobanked serum samples and questionnaire data being collected as part of the 3D (Découvrir, Développer, Devenir) cohort study that is being conducted by the Integrated Research Network on Perinatology of Québec and Eastern Ontario (IRNPQEO) to investigate the effect of various factors on birth outcomes. In this study funded by the Canadian Institutes for health Research (CIHR), 2,400 pregnant women were recruited during their first trimester between May 2010 and October 2012. Participating women have consented to have biological material collected as part of the study, including serum samples, stored in a biobank to be made available for future research.

Serum samples collected from mothers at the first trimester at the first will be tested for Toxoplasma and CMV antibodies. Mothers seronegative for either infection at their first trimester will have another sample, collected either during the third trimester or at delivery, tested for these infections. Testing results will be used to calculate rates of seroprevalence (i.e. proportion of women seropositive for IgG) at first trimester of pregnancy and of seroconversion (i.e. proportion of women seropositive for IgG at the third visit among those who were seronegative at their first visit) during pregnancy

Funding: Maternal and Infant Health Section, Public Health Agency of Canada

Toxoplasma gondii in retail meats and country foods

Project Lead: Pia Muchaal, Public Health Agency of Canada
Current information on the presence of Toxoplasma gondii in meat in Canada is limited and dated. Therefore, the Toxoplasma working group is interested in investigating the prevalence of Toxoplasma gondii in retail meats and country foods (Inuit and Aboriginal traditional foods).

Retail meat samples will include the following:
  • Chicken and beef from a variety of sources that will include the Canadian Food Inspection Agency and the PHAC’s C-Enternet program.
  • Chicken, pork chops, ground beef, and ground turkey will be acquired from the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS).
  • Other meats of interest include lamb and mutton, as these meats have been associated with infections.

Country foods tested will be acquired through FEPN members (Lena Measures and Manon Simard) and academics with an interest in environmental toxicology (Laurie Chan, University of Ottawa). The investigation will focus on the top five country foods, as well as caribou and walrus.