[Seroprevalence of Trypanosoma cruzi antibodies and associated risk factors among the population under 18 years of age in Veracruz, Mexico]. / Seroprevalencia de anticuerpos contra Trypanosoma cruzi y su asociación con factores de riesgo en menores de 18 años de Veracruz, México.

OBJECTIVES: To determine the prevalence of Trypanasoma cruzi antibodies among the population under 18 years of age in the state of Veracruz, Mexico, and to identify risk factors associated with housing conditions and vector presence and distribution. METHODS: A cross-sectional, epidemiological study of the population under 18 years of age living in 10 of the 11 health districts of the state of Veracruz, Mexico, from 2000 to 2001. Presence of T. cruzi antibodies was determined by hemagglutination inhibition test (HAI) and enzyme-linked immunosorbent assays (ELISA) of serum samples spotted on filter paper, and confirmed by HAI, ELISA, and indirect immunofluorescence assay (IFA) on serum samples. A questionnaire was administered to determined housing conditions, and entomological indices for triatomines were calculated for both the intra- and peridomiciliary areas. The results were analyzed using bifactorial and multifactorial unconditional logistic regression. RESULTS: Of the 150 individuals presenting an initial reaction, 14 were confirmed positive (5 by HAI, ELISA and IFA; 6 by HAI and ELISA, and 3 by ELISA and IFA), for a total prevalence rate of 0.91% (95% CI: 0.85-0.94). All of the confirmed-positive cases were from five of 14 health districts, with the Tuxpan district having the highest prevalence rate: 5.2% (95%CI: 1.2-9.0). Risk factors included having noticed cracks in the house walls and gaps in the roof. The only species of vector captured was Triatoma dimidiata. The entomologic indices for infestation, colonization, and natural infection were: 10.9%, 50.0%, and 9.0%, respectively. CONCLUSIONS: Active, vector-borne transmission of T. cruzi was confirmed in the state of Veracruz, Mexico, with an overall antibody seroprevalence rate of 0.19% among the population under 18 years of age. Seroprevalence rates among this segment of the population, which serves as a sentinel group, should be closely monitored to determine if more stringent methods of vector control and epidemiological surveillance are needed.

Seroprevalencia de anticuerpos contra Trypanosoma cruzi y su asociación con factores de riesgo en menores de 18 años de Veracruz, México / Seroprevalence of Trypanosoma cruzi antibodies and associated risk factors among the population under 18 years of age in Veracruz, Mexico

OBJETIVOS: Determinar la prevalencia de anticuerpos contra Trypanosoma cruzi en menores de 18 años del estado de Veracruz, México, e identificar los factores de riesgo asociados con las características de la vivienda y la presencia y distribución del agente transmisor. MÉTODOS: Estudio epidemiológico transversal en la población menor de 18 años que vivía en 10 de las 11 jurisdicciones sanitarias del estado de Veracruz, México, entre 2000 y 2001. La presencia de anticuerpos contra T. cruzi se determinó mediante una prueba de hemaglutinación indirecta (HAI) y un ensayo inmunoenzimático indirecto tipo ELISA en muestras de suero tomadas en papel de filtro y se confirmaron mediante las pruebas de HAI, ELISA e inmunofluorescencia indirecta (IFI) en muestras de suero. Se aplicó un cuestionario para evaluar las condiciones de la vivienda y se calcularon los índices entomológicos de triatominos intra y peridomiciliarios. Los resultados se evaluaron mediante análisis bifactorial y multifactorial por regresión logística no condicional. RESULTADOS: De las 150 personas inicialmente reactivas, 14 resultaron positivas (5 mediante la prueba de HAI, ELISA e IFI; 6 por HAI y ELISA y 3 por ELISA e IFI), para una prevalencia general de 0,91 por ciento (IC95 por ciento: 0,85 por ciento a 0,94 por ciento). Los casos positivos residían en cinco jurisdicciones sanitarias y la mayor prevalencia se encontró en Tuxpan: 5,2 por ciento (IC95 por ciento: 1,2 por ciento a 9,0 por ciento). Los factores de riesgo fueron el haber visto chinches dentro de la vivienda y los techos con fisuras. La única especie del agente transmisor capturada fue Triatoma dimidiata. Los índices entomológicos de infestación, colonización e infección natural fueron: 10,9 por ciento, 50,0 por ciento y 9,0 por ciento, respectivamente. CONCLUSIONES: Se confirmó la transmisión vectorial activa de la infección en el estado de Veracruz, México, con una seroprevalencia general de anticuerpos contra...

OBJECTIVES: To determine the prevalence of Trypanasoma cruzi antibodies among the population under 18 years of age in the state of Veracruz, Mexico, and to identify risk factors associated with housing conditions and vector presence and distribution. METHODS: A cross-sectional, epidemiological study of the population under 18 years of age living in 10 of the 11 health districts of the state of Veracruz, Mexico, from 2000 to2001. Presence of T. cruzi antibodies was determined by hemagglutination inhibition test (HAI) and enzyme-linked immunosorbent assays (ELISA) of serum samples spotted on filter paper, and confirmed by HAI, ELISA, and indirect immunofluorescence assay (IFA) on serum samples. A questionnaire was administered to determined housing conditions, and entomological indices for triatomines were calculated for both the intra- and peridomiciliary areas. The results were analyzed using bifactorial and multifactorial unconditional logistic regression. RESULTS: Of the 150 individuals presenting an initial reaction, 14 were confirmed positive (5 by HAI, ELISA and IFA; 6 by HAI and ELISA, and 3 by ELISA and IFA), for a total prevalence rate of 0.91 percent (95 percent CI: 0.85-0.94). All of the confirmed-positive cases were from five of 14 health districts, with the Tuxpan district having the highest prevalence rate: 5.2 percent (95 percentCI: 1.2-9.0). Risk factors included having noticed cracks in the house walls and gaps in the roof. The only species of vector captured was Triatoma dimidiata. The entomologic indices for infestation, colonization, and natural infection were: 10.9 percent, 50.0 percent, and 9.0 percent, respectively. CONCLUSIONS: Active, vector-borne transmission of T. cruzi was confirmed in the state of Veracruz, Mexico, with an overall antibody seroprevalence rate of 0.19 percent among the population under 18 years of age. Seroprevalence rates among this segment of the population, which serves as a sentinel group,...

Detection of antibodies against Trypanosoma cruzi in blood donors in the General Hospital of Mexico city / Detection of antibodies against Trypanosoma cruzi in blood donors in the General Hospital of Mexico city

A doença de Chagas é um problema importante de súde pública no México, onde estimativas recentes demonstraram a prevalência de 540 mil indivíduos infectados com o Trypanosoma cruzi. Neste trabalho deterimnou-se a sororreatividade ao T. cruzi em 2.210 doadores de sangue, no perído de 1998-2000, de 28/31 estados de México, bem como da cidade do México. Todos os soros foram testados por meio de hemaglutinação indireta e do imunoensaio enzimático (ELISA. Aplicou-se, na ocasião, um questionário para obter dados sociodemográficos. Em seguida, os indivíduos foram levados a identificar visualmente o vetor (Triatoma pallidipennis) e a assinar uma carta de consentimento. Dos 2.210 casos soros, 151 foram positivos em ambos os testes. Os indivíduos eram provenientes de 12 estados e da cidade do México, sendo 85,4 por cento homens e 14,6 por cento mulheres. Somente 14 por cento (6/151) identificaram o vetor. Essa elevada soroprevalência foi atribuída não só ao local inde foi realizado o estudo, Hospital General de México, um centro nacional de atenção à saúde, que assiste a população de todo o país, masa também ao elevado movimento migratório das áreas endêmicas para a cidade do México.

Comportamiento biológico de triatoma pallidipennis en el estado de Morelos México / Biological behavior of triatoma pallidipennis in the state of Morelos México

T. pallidipennis was found naturally infected in localities of domestic, peridomestic and wild areas in the State of Morelos, México. In agreement with the triatomines high potentiality like vectors of T. cruzi, protozoan that causes Chagasïdisease and the Knowledge of these bugs in México, the aim of the present research was to collect triatomines for assessment of T. cruzi infection, to characterize and compare life cycles, identification of feeding preferences and observe indexes of experimental infectivity. Seven isolates of T. cruzi were obtained, from differents localities which curves of parasites showed different behaviors. Histopathological study, carried out by counting of amastigotes nests, which affected the gastrocnemius muscle and heard was observed. The life cycles of T. pallidipennis was completed in 131 days. The feeding preferences were rats, cats and pigs

First case of natural infection in pigs. Review of Trypanosoma cruzi reservoirs in Mexico

An epidemiological research project was performed in the State of Morelos including collection of samples for blood smears and culture, serological tests, and xenodiagnoses from a total of 76 domestic and peridomestic mammals. Two strains of Trypanosoma cruzi were isolated by haemocultures; one from a pig (Sus scrofa), the first case of natural infection reported in Mexico, and the other from a dog (Canis familiaris). This study summarizes current information in Mexico concerning confirmed reservoirs of T. cruzi.