The CUIDA Chagas Project: towards the elimination of congenital transmission of Chagas disease in Bolivia, Brazil, Colombia, and Paraguay

ABSTRACT Background: Mother-to-child transmission of Chagas disease (CD) has become a relevant problem in both endemic and non-endemic areas. Methods: Description of the CUIDA Chagas Project - Communities United for Innovation, Development and Attention for Chagas disease'. Results: Through innovative and strategic research, this project will provide improved diagnostic and treatment options as well as replicable implementation models that are adaptable to different contexts. Conclusions: By integrating test, treat and care actions for CD into primary health care practices, the burden of CD on people and health systems may be significantly reduced.

Chagas disease. The use of serology to establish drug efficacy. Value and limitations

Presented at the "Consultative Meeting on the Strategic and Operational Aspects for the Clinical Development of Trypanocidal Drugs for Chagas Disease, 23-24 April 2007, Buenos Aires, Argentina.", sponsored by TDR, WHO.

Congenital transmission of Trypanosoma cruzi in central Brazil. A study of 1,211 individuals born to infected mothers

Transmission of Trypanosoma cruzi during pregnancy is estimated to occur in less than 20% of infected mothers; however, the etiopathogenesis is not completely understood. The Centre for Studies on Chagas Disease provides confirmation of T. cruzi infection for individuals living in central Brazil. In this retrospective hospital-based study, all requests for diagnosis of T. cruzi infection in individuals less than 21 years old from 1994-2014 were searched. We end with 1,211 individuals and their respective infected mothers. Congenital transmission of infection was confirmed in 24 individuals (2%) in central Brazil, an area where the main T. cruzi lineage circulating in humans is TcII. This low prevalence of congenital Chagas disease is discussed in relation to recent findings in the south region of Brazil, where TcV is the main lineage and congenital transmission has a higher prevalence (approximately 5%), similar to frequencies reported in Argentina, Paraguay and Bolivia. This is the first report to show geographical differences in the rates of congenital transmission of T. cruzi and the relationship between the prevalence of congenital transmission and the type of Tc prevalent in each region.

Congenital Chagas disease: an update

Congenital infection with Trypanosoma cruzi is a global problem, occurring on average in 5% of children born from chronically infected mothers in endemic areas, with variations depending on the region. This presentation aims to focus on and update epidemiological data, research methods, involved factors, control strategy and possible prevention of congenital infection with T. cruzi. Considering that etiological treatment of the child is always effective if performed before one year of age, the diagnosis of infection in pregnant women and their newborns has to become the standard of care and integrated into the surveillance programs of syphilis and human immunodeficiency virus. In addition to the standard tests, polymerase chain reaction performed on blood of neonates of infected mothers one month after birth might improve the diagnosis of congenital infection. Recent data bring out that its transmission can be prevented through treatment of infected women before they become pregnant. The role of parasite genotypes and host genetic factors in parasite transmission and development of infection in foetuses/neonates has to be more investigated in order to better estimate the risk factors and impact on health of congenital infection with T. cruzi.

Performance levels of four Latin American laboratories for the serodiagnosis of Chagas disease in Mexican sera samples

In nearly all of the previous multicentre studies evaluating serological tests for Trypanosoma cruzi infection, sera samples from Central or South American countries have been used preferentially. In this work we compared the reliability of the serological tests using Mexican sera samples that were evaluated in four independent laboratories. This included a reference laboratory in Brazil and three participant laboratories, including one in Central America and two in Mexico. The kappa index between Brazilian and Honduran laboratories reached 1.0 and the index for the Mexican laboratories reached 0.94. Another finding of this study was that the source of antigen did not affect the performance of the serological tests.

Diagnosis of Chagas disease: what has been achieved? What remains to be done with regard to diagnosis and follow up studies?

In the acute phase and in the chronic forms of Chagas disease, the etiological diagnosis may be performed by detection of the parasite using direct or indirect parasitological methods and by the presence of antibodies in the serum by way of serological tests. Several techniques are easily available, ranging from the simplest wet smear preparation to immuno-enzymatic assays with recombinant antigens that will meet most diagnostic needs. Other tests under evaluation include a molecular test using polymerase chain reaction, which has shown promising results and may be used as a confirmatory test both in the acute and chronic phases of the disease. Better rapid tests are needed for diagnosis, some of which are already under evaluation. Additionally, there is a need for tools that can identify patients cured shortly after specific treatment. Other needs include a marker for prognosis and early diagnosis of congenital transmission.

Busca retrospectiva da transmissão maternal da infecção chagásica em pacientes na fase crônica / A retrospective search for maternal transmission of Chagas infection from patients in the chronic phase

Avaliamos a transmissão maternal do Trypanosoma cruzi em 278 filhos de 145 mães com a doença crônica causada por esse protozoário, nascidos após o estabelecimento do diagnóstico materno. Usamos, nas mães e nos filhos, provas sorológicas como base do objetivo do estudo. Verificamos que ocorreram apenas duas veiculações pela modalidade citada (2/278 = 0,7 por cento). Como houve amamentação, não foi possível diferenciar, nesses casos, a transmissão congênita da adquirida pelo leite, mas, de qualquer forma, processou-se transmissão maternal, que constitui uma das modalidades alternativas de infecção pelo Trypanosoma cruzi. A metodologia empregada é mais uma dentre as diversas propostas para aquilatar a prevalência desse tipo de propagação do Trypanosoma cruzi. Ao lado da constatação fundamental, registramos fatos relacionados com a gestação, parto, puerpério, abortamento, prematuridade, nati-neomortalidade e aleitamento materno, que podem representar subsídios para melhores interpretações sobre o assunto.

Impacto do controle químico extensivo de Triatoma infestans sobre a incidência de casos agudos e a prevalência de doença de Chagas. O exemplo de Montalvânia, Minas Gerais / The impact of the extensive chemical control of Triatoma infestans on the incidence of acute cases and the prevalence of human Chagas disease. The example of Montalvânia, Minas Gerais State

A partir da emergência de um surto de casos agudos de doença de Chagas em Montalvânia, norte de Minas Gerais, Brasil, e da implantação do controle triatomínico com inseticidas, verifica-se pronta e conseqüente desaparição dos casos e redução da incidência da infecção no Município. É mostrada a evolução da implantação e do controle do Triatoma infestans em Montalvânia e a evolução da sorologia praticada na população em geral, ao longo dos últimos trinta anos.

Serodiagnosis of Trypanosoma cruzi infection using the new particle gel immunoassay - ID-PaGIA Chagas

The ID-Chagas test is a particle gel immunoassay (PaGIA). Red coloured particles are sensitised with three different synthtic peptides representing antigen sequences of Trypanosoma cruzi: Ag2, TcD and TcE. When these particles are mixed with serum containing specific antibodies, they agglutinate. The reaction mixture is centrifuged through a gel filtration matrix allowing free agglutinated particles to remain trapped on the top or distributed within the gel. The result can be read visually. In order to investigate the ability of the ID-PaGIA to discriminate negative and positive sera, 111 negative and 119 positive, collected in four different Brazilian institutions, were tested by each of the participants. All sera were previously classified as positive or negative according to results obtained with three conventional tests (indirect immunofluorescence, indirect hemaglutination, and enzyme linked immunosorbent assay). Sensitivity rates of ID-PaGIA varied from 95.7 per cent to 97.4 per cent with mean sensitivity of 96.8 per cent and specificity rates varied from 93.8 to 98.8 per cent with mean specificity of 94.6 per cent. The overall Kappa test was 0.94. The assay presents as advantages the simplicity of operation and the reaction time of 20 min. In this study, ID-PaGIA showed to be highly sensitive and specific.

Estudo multicêntrico: avaliaçäo do desempenho de conjuntos diagnósticos de hemaglutinaçäo indireta, disponíveis no Brasil, para o diagnóstico sorológico da infecçäo pelo Trypanosoma cruzi / Multicentric study: evaluation of the performance of kits for indirect hemagglutination available in Brazil for the serological diagnosis of the infection by Trypanosoma cruzi

Por iniciativa da Coordenaçäo do Sistema de Laboratórios de Saúde Pública (COLAB), da Fundaçäo Nacional da Saúde instituiu um comitê composto por diferentes membros da comunidade científica e de serviços, com a finalidade de avaliar os conjuntos diagnósticos (CDs), concretizados no Brasil, para o diagnóstico sorológico da tripanosomíase americana (doença de Chagas). Cinco laboratórios avaliaram 11 CDs para o teste de hemaglutinaçäo indireta, disponíveis no mercado, seguindo as instruçöes de cada fabricante. Cada CD foi testado através dos resultados obtidos num painel com 87 soros (52 reagentes e 35 näo reagentes), provenientes das sorotecas dos mesmos laboratórios participantes da avaliaçäo. O critério para reatividade adotado nas amostras do painel baseou-se nos resultados obtidos com os testes imunoenzimático (ELISA) e de imunofluorescência indireta (diluiçäo de 1:40)...

Correlaçäo entre a sintomatologia e a evoluçäo do mesaesôfago / Correlation between the symptoms and the stage of the megaesophagus

Em um estudo prospectivo de 500 casos de mesaesofago, os autores analisaram a correlaçäo existente entre a sintomatologia e a evoluçäo desta afecçäo, tomando por base o seu estadiamento em 4 grupos radiológicos, de acordo com a classificaçäo de Rezende e cols. Dos 500 pacientes, 280 (56 por cento) eram do sexo masculino e 220 (44 por cento) do sexo feminino. As idades variaram de 7 a 82 anos (média de 45,1, mediana de 45 anos) com sorologia positiva em 453 pacientes (90,6 por cento). Foram analisados os seguintes sintomas: disfagia presente em 96,6 por cento dos pacientes; regurgitaçäo em 65,2 por cento; dor esofagiana em 59,3 por cento; odinofagia em 56,2 por cento; pirose em 32,2 por cento e obstipaçäo intestinal em 51 por cento. Foram ainda avaliados o déficit ponderal como indicador do estado nutricional e a hiportrofia das parótidas...