Cats are the definitive hosts of Toxoplasma gondii. Infected cats excrete oocysts in their feces, infecting humans and other animals. The objective of the present study was to determine the presence of anti-Toxoplasma antibodies in cat owners and their pets, and determine if there was a relationship between Toxoplasma infection and humans who live with infected cats. IgG anti-Toxoplasma antibodies in sera of 59 cat owners were determined by enzyme-linked immunosorbent assay (ELISA), in 24 sera from their cats, IgG, IgM, and IgA antibodies were found using Burney's ELISA. Thirty-eight (64%) of 59 cat owners were positive to IgG anti-Toxoplasma. Seropositivity for cats was 70.8% IgG, 8.3% IgM, and 62.5% IgA. Cohabitation with cats infected by T. gondii, feeding with leftovers or raw viscera, and lack of control over how their feces were handled are risk factors conducive for humans to become infected by T. gondii.

Los felinos son huéspedes definitivos de Toxoplasma gondii. Los gatos infectados excretan ooquistes en sus heces, infectando a humanos y a otros animales. El propósito de este estudio fue determinar anticuerpos anti-Toxoplasma en dueños de gatos y sus mascotas y conocer si existía relación entre la infección por Toxoplasma en humanos que conviven con gatos infectados. Se determinaron anticuerpos anti-Toxoplasma IgG en 59 sueros de dueños de gatos por el método de ELISA (Sigma), y en 24 sueros de sus gatos anticuerpos IgG, IgM e IgA por ELISA de Burney. Los dueños de gatos fueron positivos a IgG anti-Toxoplasma 38/59 64%. La seropositividad de gatos fue de 70.8% IgG, 8.3% a IgM y 62.5% IgA. Cohabitar con gatos infectados por T. gondii dentro del hogar, alimentarlos con desechos de mesa o vísceras crudas y la falta de control de sus heces son factores de riesgo para adquirir infección por T. gondii en el humano.

Com a aparição do vírus de inmunodeficiência humana (VIH), a prevalência de toxoplasmosis tem aumentado demais. Em dos pacientes com o síndrome de inmunodeficiência, a toxoplasmosis é a principal causa de morte. A incidência, de anticorpos nesse tipo de pacientes depende da prevalência da população onde se apresenta a doença. O método de Enzima Inmuno Ensaio absorvemnte (ELISA) foi aplicado a 92 pacientes para determinar si eram positivos a anticorpos anti-Toxoplasma IgG e IgM. O resultado foi: 46 (50.5%) foram seropositivos e un caso apresentou anticorpos IgM. D estos 92 pacientes, 53 apresentavam o virus de inmunodeficiência humana (HIV) y 39 tinham SIDA. A determinação e o "monitoreo" de anticorpos anti-Toxoplasma em pacientes com HIV é indispensável, pois uma taxa elevada destos pacientes pode desenvolver a toxoplasmosis cerebral, a causa principal de morte nessos pacientes.

With the emergence of the human immunodeficiency virus (HIV), in patients with acquired immunodeficiency syndrome (AIDS), Toxoplasma gondii has arisen as an important opportunist pathogenic agent, especcially in the central nervous system, being the most common cause of intracerebral lesions. The incidence of Toxoplasma gondii in HIV-infected patients depends principally on the existence of latent Toxoplasma parasitosis in the population affected. Through the enzyme-linked immunosorbent assay (ELISA), IgG and IgM anti-Toxoplasma antibodies were found in 92 patients of which 46 (50.0%) were IgG seropositive, and only one case (1.0%) had IgM antibodies.Of the 92 patients: 53 were HIV seropositives and 39 had AIDS. The detection and monitoring of anti-Toxoplasma antibodies in HIV patients is essential, since in this group there is a high percentage risk of developing cerebral toxoplasmosis, which is the second cause of death in this type of patients.