Toxoplasmosis, a highly prevalent disease, is mainly diagnosed by serology. Incidence studies could be feasible in children, but ethical concerns restrict blood sampling in this group. Saliva contains small amounts of crevicular fluid IgG. Dot-ELISA and a protein A IgG capture immunoassay were standardized for anti-Toxoplasma gondii IgG in paired saliva and serum samples from 20 adult volunteers. A frequency of toxoplasmosis of 19% (95% CI 12-28) was found in 100 saliva samples from university graduates using both assays. Toxoplasmosis immunoassays using saliva IgG are a promising tool for the investigation of the epidemiology of this disease in children and other vulnerable groups.

School-age children are a social group in which blood collection for laboratory testing can be perceived as an invasive procedure, with low acceptance and tolerance of stakeholders. This problem could be circumvented by replacing serum samples with saliva. For this purpose, and to make the collection of saliva samples playful and instructive for children, educational activities on hygiene and toxoplasmosis transmission and prevention were performed using toys and audiovisual tools. The target audience consisted of 7-10 year-old children from low-income families who attended public schools in the city of São Paulo. Saliva samples were used in a previously described in-house Enzyme-Linked Immunosorbent Assays (ELISA) to detect anti- Toxoplasma gondii IgG antibodies and establish the immunological status of each of the participants. One year later, children’s memory and fixation of concepts regarding hygiene habits, as well as transmission and prevention of toxoplasmosis were tested in the same schools, by means of a questionnaire application, using students who did not participate in the first intervention as controls. The prevalence of positive anti- T. gondii IgG among students was 50% (82/164). One year later, 45 children had more knowledge on toxoplasmosis (28/45 vs 29/147) and they drew the cat’s involvement in the transmission of toxoplasmosis more often than controls (28/45 vs 29/147). Sorted according to the presence of specific IgG in saliva, recovered positive students presented worse memory of the above cited knowledge as did saliva-negative IgG students, but both groups had isolated higher frequency of fixed knowledge than non-intervened students. Our data show that there is a high prevalence of T. gondii infection in school-children from low-income areas; saliva is an alternative to blood for anti- T. gondii IgG detection; and a one-day educational intervention in school-children was effective in promoting knowledge fixation on hygiene and toxoplasmosis transmission and prevention after one year.

Non family health education is controversial by the different family models and is done in a contemplative way, which generates small fixation of concepts or behavioral changes and the child may have flawed personal sanitary concepts. As the school offers only a contemplative view, individual interactive experiences could pinpoint and emphasize these concepts. With this, the Institute of Tropical Medicine of the University of São Paulo and the Faculty of Medicine of the University of São Paulo, with the support of the Pro-Rectory of Extension and Culture of University of São Paulo, we constructed an interactive exhibition for students of public schools of the fundamental cycle, addressing the essential concepts of disease transmission and prevention. An initial contemplative view was offered during the waiting queue, then each individual performs experiments of interpersonal contact, transmission by fomites, variation of agents, and "contamination" is demonstrated by fluorescent lighting. The interaction was presented in 5 public schools, with intense collaboration of the students and teachers, with 1300 students participating in all experiments with more than 70% participation. Events of this type, which raise awareness about hygiene and the transmission and prevention of communicable diseases can be done interactively among students, allowing greater fixation and greater acceptance. The exposition is interactive with active participation of students in essays and revelation of landmark events, such as demonstrating interpersonal contamination at various levels of personal relationship.

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Sampaio BFC. Desenvolvimento de ensaios imunoenzimáticos para otimização da detecção de IgG anti-T.gondii em saliva humana (dissertação).