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Objective The purpose of the present study is to standardize and evaluate the use of the immunoglobulin G (IgG) antibody avidity test on blood samples from newborns collected on filter paper to perform the heel test aiming at its implementation in ongoing programs. Methods Blood samples from newborns were collected on filter paper simultaneously with the heel prick test. All samples were subjected to immunoglobulin M IgM and IgG enzyme-linked immunosorbent assays (ELISA). Peripheral blood was collected again in the traditional way and on filter paper from newborns with high IgG levels (33). Three types of techniques were performed, the standard for measuring IgG in serum, adapted for filter paper and the technique of IgG avidity in serum and on filter paper. The results of the avidity test were classified according to the Rahbari protocol. Results Among the 177 samples, 17 were collected in duplicate from the same child, 1 of peripheral blood and 1 on filter paper. In this analysis, 1 (5.88%) of the 17 samples collected in duplicate also exhibited low IgG avidity, suggesting congenital infection. In addition, the results obtained from serum and filter paper were in agreement, that is, 16 (94.12%) samples presented high avidity, with 100% agreement between the results obtained from serum and from filter paper. Conclusion The results of the present study indicate that the avidity test may be another valuable method for the diagnosis of congenital toxoplasmosis in newborns. Resumo Objetivo O objetivo do presente estudo é padronizar e avaliar a utilização do teste de avidez de anticorpos imunoglobulina G (IgG) em amostras de sangue de recémnascidos (RNs) coletadas em papel filtro para a realização do teste do pezinho visando a implementação nos programas já vigentes. Métodos Foram coletadas amostras de sangue de recém-nascidos em papel filtro simultaneamente ao teste do pezinho. Em todas as amostras, foram realizados os testes imunoenzimáticos (ELISA) imunoglobulina M (IgM) e IgG. Dos RNs que apresentaram altos índices de IgG (33), foi novamente coletado sangue periférico da forma tradicional e em papel filtro. Foram realizadas técnicas padrão para a dosagem de IgG em soro, adaptadas para papel filtro, e a técnica de avidez de IgG em soro e em papel filtro. Os valores obtidos para o teste de avidez foram classificados de acordo com o protocolo de Rahbari. Resultados Dentre as 177 recoletas, em 17 amostras foi realizada a coleta simultânea de sangue periférico e papel filtro da mesma criança. Nesta análise, 1 (5,88%) das 17 amostras coletadas em duplicata obteve também baixa avidez de IgG, sugerindo infecção congênita da criança, e houve concordância entre os resultados obtidos em soro e em papel filtro: 16 (94,12%) das amostras apresentaram alta avidez, com concordância de 100% entre os resultados obtidos em soro e em papel filtro. Conclusão Os dados do presente trabalho evidenciam que o teste de avidez poderá ser mais um método valioso a ser utilizado no diagnóstico da toxoplasmose congênita em RNs.

The present study aimed to evaluate the spatial distribution and risk factors for infection by Toxoplasma gondii in sheep in the state of Goias, located in the central-western region of Brazil. Through the immunofluorescence antibody test (IFAT), the seroprevalence of anti-T. gondii antibodies was analyzed in 1000 blood serum samples obtained from sheep in all macro and micro regions of the state of Goias. Data related to sex, age of the animals, size of the farm, type of farm, water source, veterinary assistance, replacement of the herd, presence of domestic cats, presence of wild cats and presence of other wild animals were obtained at the sampling time. The differences between the seroprevalences obtained in relation to the variables analyzed were estimated using Pearson's chi-square test (χ2). The odds ratio (OR) values for each risk factor evaluated were statistically analyzed with a confidence interval of 95%. Positivity for IgG anti-T. gondii was observed (titer ≥64) in 34.3% (343/1000) of the samples, which ranged from 26.9% (31/115) to 44.2% (53/120) and from 21.8 (12/55) to 55.2% (16 / 29), respectively in the analyzed mesoregions and microregions. In all investigated regions of the State of Goias, serum-reactive animals were detected with the age of the animals, the source of water, the form of replacement of the herd and the presence of domestic cats and wild animals risk factors statistically associated with the occurrence of T. gondii in animals.

Toxoplasma gondii can cross the placental barrier, causing fetal infection with potentially severe sequelae. The aim of this study was to evaluate whether the serological screening for toxoplasmosis should be included in the basic neonatal heel prick test in order to establish criteria for the confirmation and/or exclusion of the diagnosis of congenital infection in newborns treated at three public health units in the metropolitan region of Goiania, Goias State, Brazil. Blood samples were collected on filter paper from newborns and later, peripheral blood samples from the mothers and their respective children were obtained to confirm or exclude the diagnosis of suspected congenital infection, by means of an enzyme-linked immunosorbent assay (IgM and IgG) and a polymerase chain reaction assay. From a total of 1,159 blood samples collected on filter paper, 43.92% were reactive to IgG and 0.17% to anti-T. gondii IgM and IgG. One hundred and twenty-seven paired samples (mother and child) were collected following consensual protocols for peripheral blood collection. Results obtained from the filter paper and peripheral blood of the newborns were 90.55% concordant. A comparison of the mother and child blood test results showed agreement regarding the detection of IgG in 90.48% of the samples. The parasite DNA was detected in the peripheral blood of one child. In view of the results obtained in this study, the inclusion of the serological screening for toxoplasmosis in the newborn heel prick test proved to be effective for the early detection of congenital T. gondii infection.

Introduction: Since 1990 the standard treatment for toxoplasmosis has remained the same. The therapy is based on a synergistic combination of pyrimethamine and sulfadiazine, drugs that promote synthesis blockade and decrease of tachyzoite folic acid levels. This therapy acts only on the tachyzoite forms of the parasite, not affecting bradyzoites present in tissue cysts that persist in the individual during the chronic phase and not preventing possible disease reagudization even after treatment. Given the high seroprevalence of toxoplasmosis in the general population and the serious complications that this infection may bring to the patient, a safe and effective treatment against all morphological forms is necessary. The repositioning of drugs main objective is to use substances already marketed to treat other diseases. Thus, Atovaquone, which is an antimalarial of the naphthoquinone group recently accepted by the FDA and isn’t yet part of the routine treatment protocols employed for toxoplasmosis, should be studied, as recent studies show its activity against tachyzoites and also against bradyzoites, representing a huge advantage over the drugs currently used. It also does not interfere with folic acid metabolism, proving to be a promising drug in the treatment of pregnant women. Objective: The present study aims to evaluate the effects of atovaquone on T. gondii strains RH and ME49 (type I and type II, respectively) in vitro. Methodology: In quintuplicate, murine RAW 264.7 macrophages were used in six-well culture plates with 3mL of supplemented RPMI medium, where 200.000 cells were seeded and incubated at 37°C, 5% de CO2 for 24 hours. After this period, the culture was infected with 1×106 tachyzoites/well of each strain analyzed and simultaneously treated with 100 nM Atovaquone. The parasites were analyzed by optical microscopy and quantified in a Neubauer chamber at 24h, 48h, 72h and 7 days. Results: For the RH strain, the control group showed steady growth, starting at 60.000 forms/mL within 24 hours, reaching 2.550.000/mL within 7 days. When treated with Atovaquone, within 24 hours the number detected was 30.000/mL, with decline in growth resulting in only 15.000/mL observed after the first week of cultivation. Similar results were observed with the Me49 strain, which at the beginning of the experiment had 150.000/mL tachyzoites in the untreated group and 90.000/mL in the treated group and, at the end of 7 days, 1.950.000/mL tachyzoites in the untreated group and 30.000/mL in the treated group. Conclusion: Atovaquone has shown great activity in controlling Toxoplasma gondii parasite replication in vitro. Financial Support: FAPEG (Fundacao de Amparo a Pesquisa do Estado de Goias)

Toxoplasmosis is caused by Toxoplasma gondii and the probability of this infection occurring in the first months of life is usually low because its transmission is related to eating habits. A 6-month-old nursing infant was diagnosed with acute toxoplasmosis, which was identified through anti- T. gondii IgA, IgM and low-avidity IgG serologic assays, polymerase chain reaction (PCR) and mouse bioassay test although its mother was seronegative. This serological divergence between mother and child led us to interview the mother regarding epidemiological factors. During this interview, she reported that she had given her 2-month-old baby a piece of undercooked beef to suck on. After some time, the baby presented fever and cervical lymphadenitis. This report emphasizes the importance of serological surveys of toxoplasmosis in nursing infants presenting with fever and lymphadenitis, in view of the possible acquisition of toxoplasmosis in the first months of life.

Desde os tempos remotos acredita-se que o pensamento educacional seja de grande importância nos diversos setores da sociedade, sendo alvo de constante reflexão de estudiosos da área. O pensamento educacional na saúde foi proposto tardiamente embora a populaçao carecesse de idéias e açoes que visassem educar para previnir, buscando uma melhora na qualidade de vida da população, pois muitas doenças eram adquiridas por falta de informação. No século XX a população era alvo de epidemias como por exemplo febre amarela e varíola o que despertou a preocupaçao dos profissionais de saúde e da classe governamental, fazendo com que nomes como Oswaldo Cruz tivessem sua importância neste contexto. Propostas educacionais em que profissionais de saúde ouvem e educam pequenos grupos de pessoas são uma opçao para o desenvolvimento dessas políticas educacionais, supostamente esses profissionais são os mais indicados para tais atividades educacionais pois são os maiores portadores dos conhecimentos práticos e da realidade da saúde, podendo esclarecer e orientar da melhor maneira a população que carece desse sistema educacional, porém uma dificuldade vêm sendo encontrada para essa prática pois esses profissionais apresentam uma carência na didática.