Prevalence of toxoplasma gondii in humans and canines in the Capital District

Introduction: Toxoplasmosis is zoonotic disease caused by protozoan Toxoplasma gondii. It has a high impact on public health since 5 to 90% of the general 20-30-yr-old population –depending on the geographic area– has been in contact with this microorganism. It has particular epidemiological characteristics such as low morbidity and mortality rates. Both fetus and immunodefficient patients have a special risk of serious disease. It affects pets and wild animals, both mammals and birds. Materials and methods: A cross-sectional epidemiologicalstudy was made to find the serological prevalence of T. gondii in humans and dogs in the Capital District. The sample size was established according to the methodology for estimating disease prevalence in large populations. Serum from 1,307 people was obtained and processed from August to December 2006. In order to detect specific IgG antibodies vs. gondii, the ELISA T. Gondii kit from Vircell S.A. (ref. G1027) was used. The sensitivity of this test is 99% and its specificity is 99%. In humans, the serum samples were considered positive above 9.9 IU/ml and negative below this value. At the same time, 795 canine serum samples collected in the same period were processed. Canine serum samples were tested to determine IgG antibody level for T. Gondii. Results: Serum samples with values greater than or equal to 5.0 IU/ml were considered positive. The prevalence found for human females was 50.2 and for males 48.9. In canines, female prevalence was 3.90 and male prevalence was 5.66. The findings in humans and canines are consistent with those reported in studies conducted worldwide on toxoplasmosis, which show that the prevalence of infection are high and may vary depending on weather conditions, food habits and health and socioeconomic status. Keywords: Toxoplasmosis, prevalence, risk factors, epidemiologic study, zoonosis.