Revista Panamericana de Salud Pública, Volume: 21, Issue: 6, Published: 2007
  • The validity of a presumptive diagnosis of cutaneous leishmaniasis performed by community health workers in Colombia Artículos

    Sánchez, Juana; Orozco, Luis; Buendía, Jefferson; Muñoz, Gerardo

    Abstract in Spanish:

    OBJETIVO: Validar el método de diagnóstico presuntivo de leishmaniasis cutánea basado en la observación de criterios clínico-epidemiológicos, realizado por trabajadores comunitarios en temas de salud (TCS) en tres municipios endémicos del departamento de Santander, Colombia. MÉTODOS: Estudio de evaluación de tecnologías diagnósticas basado en un muestreo de corte transversal de casos sospechados de leishmaniasis cutánea en tres municipios endémicos de leishmaniasis del departamento de Santander (Rionegro, El Playón y Landázuri). Los TCS previamente capacitados realizaron el diagnóstico presuntivo de leishmaniasis cutánea entre octubre de 2004 y noviembre de 2005 y tomaron muestras para el diagnóstico confirmatorio mediante el método de tinción según Field, el de cultivo y la reacción en cadena de la polimerasa. Como criterios de validez del diagnóstico presuntivo realizado por los TCS se utilizaron la sensibilidad, la especificidad y los valores predictivos positivo y negativo. La reproducibilidad entre evaluadores se estimó mediante la concordancia observada. RESULTADOS: De los 196 pacientes estudiados, 33 (16,8%) fueron negativos y 163 (83,2%) fueron positivos según las pruebas de laboratorio. Para todos los grados de certeza del diagnóstico clínico, la sensibilidad estuvo entre 52% y 98% (k [1,0] = 39,0%) y la especificidad entre 9% y 55% (k [0,0] = 14,0%). El área bajo la curva ROC fue de 56,5% (IC95%: 45,6 a 67,4). La proporción de acuerdos positivos y negativos fue de 86,3% y 43,5%, respectivamente. CONCLUSIONES: La sensibilidad del diagnóstico presuntivo realizado por los TCS supera la de los métodos de diagnóstico parasitológicos empleados habitualmente en las zonas endémicas, sin embargo, su especificidad es mucho menor. A pesar de que este diagnóstico no es útil como prueba de diagnóstico de la leishmaniasis cutánea o como criterio para proceder o no al tratamiento, se demostró su utilidad como prueba de captación activa de casos en la comunidad.

    Abstract in English:

    OBJECTIVE: To validate a method for the presumptive diagnosis of cutaneous leishmaniasis based on the observation of clinical-epidemiological criteria, carried out by community health workers in three endemic municipalities in Santander, a department in northeastern Colombia. METHODS: This evaluation study of diagnostic technologies was based on a cross-sectional sampling of suspected cases of cutaneous leishmaniasis in the municipalities of Rionegro, El Playón, and Landázuri. After being trained, the community health workers carried out the presumptive diagnoses of cutaneous leishmaniasis between October 2004 and November 2005. At the time of diagnosis, the health workers also collected samples for confirmatory diagnosis through Field's stain method, culturing, and polymerase chain reaction. Four criteria were used to assess the validity of the presumptive diagnoses carried out by the health workers: sensitivity, specificity, positive predictive value, and negative predictive value. Replicability among the health workers was estimated through their observed level of agreement. RESULTS: According to the laboratory tests, of the 196 patients studied, 33 (16.8%) were negative and 163 (83.2%) were positive. For all the levels of certainty of the clinical diagnosis, the sensitivity was between 52% and 98% (k(1, 0) = 39.0%) and the specificity between 9% and 55% (k(0, 0) = 14.0%). The area under the receiver operating characteristic curve was 56.5% (95% confidence interval: 45.6% to 67.4%). The proportion of positive agreement and of negative agreement was 86.3% and 43.5%, respectively. CONCLUSIONS: The sensitivity of the presumptive diagnosis carried out by the health workers surpasses that of the parasitological diagnostic methods generally used in the three endemic areas, but its specificity is much lower. Even though this approach is not useful as a diagnostic test for cutaneous leishmaniasis or as a criterion for deciding to proceed with treatment or not, the method is useful for the active identification of cases in the community.
  • Cost-effectiveness of childhood hepatitis A vaccination in Argentina: a second dose is warranted Articles

    Ellis, Alejandro; Rüttimann, Ricardo W.; Jacobs, R. Jake; Meyerhoff, Allen S.; Innis, Bruce L.

    Abstract in Spanish:

    OBJETIVOS: Investigar la efectividad en función del costo de la vacunación infantil contra la hepatitis A en las cinco regiones de Argentina y determinar si la adición de una segunda dosis al esquema actual de una dosis aumentaría los beneficios a la salud y si estos justificarían el costo adicional. MÉTODOS: Se empleó el modelo de Markov para valorar cuatro opciones de vacunación para la cohorte nacida en el año 2005: 1) no vacunar; 2) vacunar a los 12 meses de edad; 3) vacunar a los 12 y a los 72 meses; y 4) vacunar a los 12 y a los 18 meses de edad. Se estimaron el costo y las consecuencias de la enfermedad a 50 años. La efectividad en función del costo de la primera y la segunda dosis de la vacuna se calculó a partir de varios precios de la vacuna e hipótesis acerca de la duración de la protección. Los costos y los beneficios para la salud (medidos en años de vida ajustados por la calidad de vida) se ajustaron por los valores actuales utilizando una tasa de descuento anual de 3%. RESULTADOS: Se estima que la política de vacunación con una dosis reduciría la probabilidad de cada miembro de la cohorte de padecer hepatitis A sintomática en 50 años de 7,2% a 4,1%. Una segunda dosis reduciría esa probabilidad a 2,0%-2,2%. La vacunación a los 12 meses de edad, a los 12 y a los 72 meses, o a los 12 y a los 18 meses reduciría el número de casos entre los contactos personales en 82%, 87% y 92%, respectivamente. La primera dosis de la vacuna satisfaría los estándares aceptados de efectividad en función del costo en todas las regiones del país y reduciría los costos en las regiones Nordeste, Central y Sur. La aplicación de una segunda dosis a los 18 meses resultaría efectiva en función del costo en todas las regiones y reduciría adicionalmente los costos en la región de Cuyo. Si la duración de la protección con una dosis fuera menor de la esperada, la segunda dosis tendría una mayor efectividad en función del costo. CONCLUSIONES: La primera dosis de la vacuna contra la hepatitis A genera mayores beneficios a la salud que la segunda. Sin embargo, este análisis sustenta la efectividad en función del costo de aplicar ambas dosis a los niños en Argentina.

    Abstract in English:

    OBJECTIVES: To investigate the cost-effectiveness of childhood vaccination against hepatitis A in the five geographic regions of Argentina, and to determine whether adding a second dose to the current one-dose schedule would provide health gains justifying its added cost. METHODS: A Markov model was used to consider four immunization options for the 2005 birth cohort: (1) no vaccination; (2) vaccination at 12 months of age, (3) vaccinations at 12 and 72 months of age; or (4) vaccinations at 12 and 18 months of age. Hepatitis A costs and consequences were predicted over 50 years. The cost-effectiveness of first and second vaccine doses was assessed through a range of vaccine prices and assumptions regarding the duration of vaccine protection. Costs and health gains (measured in quality-adjusted life years) were adjusted to present values using a 3% annual discount rate. RESULTS: The one-dose vaccination policy is predicted to reduce each birth cohort member's 50-year probability of overt hepatitis A from 7.2% to 4.1%. A second dose would reduce the probability to between 2.0% and 2.2%. Vaccination at 12 months of age, at 12 and 72 months, or at 12 and 18 months would reduce cases among personal contacts by 82%, 87%, and 92%, respectively. The first vaccine dose would meet accepted standards of cost-effectiveness in each region, and reduce costs in the Northeast, Central, and South regions. Adding a second dose at age 18 months would be cost-effective in each region, and further reduce costs in the Cuyo region. If the duration of protection with one dose is less than anticipated, the second dose would be more cost-effective. CONCLUSIONS: Greater health gains are derived from the first than second hepatitis A vaccine dose. However, this analysis supports the cost-effectiveness of providing both first and second doses to Argentina's children.
  • Timely implementation of interventions to reduce vertical HIV transmission: a successful experience in Brazil

    Amaral, Eliana; Assis-Gomes, Francisco; Milanez, Helaine; Cecatti, José Guilherme; Vilela, Maria Marluce; Silva, João Luiz Pinto e

    Abstract in Portuguese:

    OBJETIVO: Descrever o impacto da implementação oportuna de novas condutas recomendadas por consensos clínicos nacionais dirigidos à prevenção da transmissão vertical de HIV na maternidade de um hospital universitário público no Brasil. MÉTODO: Realizou-se um estudo retrospectivo de coorte dos partos de mulheres infectadas pelo HIV atendidos na instituição de 1990 a 2000. As condutas adotadas nesse período foram: 1) até 1994, amamentação contra-indicada, sem uso de drogas anti-retrovirais; 2) de 1995 a 1996, uso de zidovudina (AZT) pela gestante e pelo recém-nascido; 3) de 1997 a 1998, uso de AZT conforme protocolo ACTG 076; e 4) de 1999 a 2000, terapia anti-retroviral múltipla e cesárea eletiva. Em todos os períodos, a distribuição das drogas foi gratuita. Foram calculadas as taxas de transmissão nas quatro fases e as razões de risco de transmissão congênita para as fases e para cada intervenção profilática (amamentação, tipo de terapia anti-retroviral, tipo de parto). RESULTADOS: Foram estudadas 197 gestações. Houve redução na transmissão vertical da primeira para a quarta fase, de 32,3 para 25,7, 2,2 e 2,9%. A maior queda, observada na terceira fase, ocorreu após a introdução do esquema completo do ACTG 076. O uso de terapia anti-retroviral combinada aumentou de 0% na primeira fase para 46,4% na quarta fase. Não houve nenhum caso de transmissão vertical nas gestantes tratadas com múltiplas drogas. O risco de transmissão vertical foi 5 vezes maior com amamentação do que sem amamentação (razão de risco = 5,06), 5 vezes maior sem terapia anti-retroviral contra uso do esquema ACTG completo (razão de risco = 5,29) e 4 vezes maior para parto com fórcipe contra cesárea eletiva (razão de risco = 4,13). CONCLUSÃO: A adoção oportuna de intervenções atualizadas, recomendadas por consenso nacional de especialistas, com provisão gratuita de drogas, mostrou-se eficiente para reduzir a transmissão congênita do HIV.

    Abstract in English:

    OBJECTIVE: To describe the impact, at the public maternity facility of a university hospital in Brazil, of the rapid implementation of new guidelines recommended by national consensus panels concerning the prevention of vertical HIV transmission. METHOD: We performed a retrospective study of deliveries by HIV-infected women at the public maternity facility of a university hospital in the city of Campinas, São Paulo, Brazil, from 1990 through 2000. The guidelines utilized at the facility during this period were: (1) from 1990 through 1994, contraindication to breast-feeding and no use of antiretroviral drugs; (2) 1995 and 1996, use of zidovudine (AZT) by the pregnant woman and the newborn; (3) 1997 and 1998, use of AZT according to the ACTG 076 protocol; and (4) 1999 and 2000, multiple antiretroviral agents and elective cesarean delivery. All the antiretroviral drugs were provided for free by Brazil's public health care system. The vertical transmission rate was calculated for each of the four stages, and the risk ratio for congenital transmission was calculated for each stage and for each prophylactic intervention separately (breast-feeding, type of antiretroviral drug, type of delivery). RESULTS: We studied 197 deliveries at the public maternity facility over that 1990-2000 period. Over the four stages, the rate of vertical transmission decreased: it was 32.3% in the first stage, 25.7% in the second, 2.2% in the third, and 2.9% in the fourth. The most pronounced decrease, observed from the second to the third stage, occurred after introduction of the full ACTG 076 regimen. The use of combined antiretroviral agents increased from 0% in the first stage to 46.4% in the fourth stage. There were no cases of vertical transmission in pregnant women treated with multiple drugs. The risk of vertical HIV transmission was 5 times as great with breast-feeding vs. no breast-feeding (risk ratio = 5.06), 5 times as great with no antiretroviral therapy vs. the full ACTG 076 regimen (risk ratio = 5.29), and 4 times as great with forceps delivery vs. elective cesarean delivery (risk ratio = 4.13). CONCLUSION: The timely adoption of up-to-date interventions recommended by national consensus panels, along with the free provision of antiretroviral drugs, was effective in reducing congenital HIV transmission in this public maternity facility. The interaction between the university hospital health service and the public health service reduced the time needed for implementation of proven, effective interventions, and this experience could serve as an example for other maternal and perinatal health situations.
  • The relationship between nutritional and sociodemographic factors and the likelihood of children in the Dominican Republic having a BCG scar Articles

    Pérez-Then, Eddy; Shor-Posner, Gail; Crandall, Lee; Wilkinson, James

    Abstract in Spanish:

    OBJETIVOS: Evaluar críticamente la prevalencia de cicatrices por la vacunación con el bacilo de Calmette-Guérin (BCG) en niños de 6 a 9 años de la República Dominicana y examinar la relación entre los factores nutricionales y socioeconómicos y la probabilidad de tener cicatriz de BCG. MÉTODOS: Para este estudio correlacional se empleó la base de datos del II Censo Nacional de Talla y Peso en Escolares de Primer Grado de Básica, realizado en la República Dominicana entre agosto de 2001 y mayo de 2002, para evaluar críticamente el nivel de cobertura nacional de la vacunación con BCG. Entre la información censal de los niños estaban si tenían cicatriz de BCG, su estado nutricional y sus datos demográficos básicos. Se desarrolló un nuevo indicador sociodemográfico, el "índice de Rosa", para analizar la posible influencia de la pobreza y de otras características ambientales en la presencia de esa cicatriz. Se emplearon modelos de regresión logística para predecir la presencia de la cicatriz de BCG. RESULTADOS: La prevalencia general de cicatrices de BCG fue de 55,3% (85 644/ 154 887). Los niños desnutridos presentaron una menor probabilidad de tener cicatriz de BCG que los niños con un adecuado estado nutricional (razón de posibilidades = 0,91; intervalo de confianza de 95%: 0,87 a 0,95; P < 0,05). Los niños de 7-9 años tuvieron menor probabilidad de tener cicatriz de BCG que los niños de 6 años. Los niños de zonas del país que se encuentran a más de dos horas de viaje de Santo Domingo, la capital, presentaron menor prevalencia de cicatrices de BCG con mayor frecuencia que los niños de Santo Domingo. Se encontró correlación entre tener un mayor índice de Rosa (mejor nivel en las características socioeconómicas) y una mayor prevalencia de cicatrices de BCG (r = 0,54; P < 0,05). CONCLUSIONES: Los resultados del presente estudio indican que la cobertura de vacunación de escolares con la vacuna BCG parece no ser la adecuada en la República Dominicana. Sin embargo, la presencia de la cicatriz de BCG en una mayor proporción de niños más pequeños puede indicar que esa cobertura ha mejorado en años recientes. Se debe hacer un mayor énfasis programático y económico para extender la vacunación temprana con BCG a las áreas del país donde la cobertura de vacunación es menor y para analizar el papel que puede estar desempeñando la pobreza en la eficacia de la vacunación.

    Abstract in English:

    OBJECTIVES: To critically assess the prevalence among schoolchildren 6 to 9 years of age throughout the Dominican Republic of a bacille Calmette-Guérin (BCG) vaccination scar, and to examine the relationship between nutritional and sociodemographic factors and the likelihood of having a BCG scar. METHODS: This correlational study used the database of the Second National Census on Height and Weight of Elementary School First Grade Students, which was conducted in the Dominican Republic August 2001-May 2002, to provide a critical assessment of BCG coverage nationwide. The Census information for the children included the presence of BCG scar, their nutritional status, and basic demographic data. We developed a new sociodemographic indicator, the "Rosa Index," to examine the potential influence of poverty and other environmental characteristics on scar presence. We used logistic regression models to predict the presence of a BCG scar. RESULTS: An overall BCG scar prevalence of 55.3% (85 644/154 887) was found. Malnourished children were less likely to have a BCG scar than were children with adequate nutritional status (odds ratio = 0.91; 95% confidence interval: 0.87, 0.95, P < 0.05). Children who were 7-9 years old were less likely to have a BCG scar than were children 6 years old. Children in the areas of the country more than two hours' driving distance from the capital city of Santo Domingo more often exhibited lower BCG scar prevalence levels than did children in Santo Domingo. A higher Rosa Index (better level of socioeconomic characteristics) was correlated with higher BCG scar prevalence values (r = 0.54, P < 0.05). CONCLUSIONS: Our study findings indicate that BCG coverage appears to be inadequate for schoolchildren in the Dominican Republic. Nevertheless, the presence of a scar in a higher proportion of younger children suggests that coverage has improved in recent years. More programmatic and economic emphasis needs to be placed on extending early BCG vaccination coverage to the areas of the country where vaccination coverage is lower, and on examining the potential role that poverty may have on vaccination effectiveness.
  • Trends in mortality from scorpion stings in Mexico, 1979-2003 Artículos

    Celis, Alfredo; Gaxiola-Robles, Ramón; Sevilla-Godínez, Elizabeth; Valerio, María de Jesús Orozco; Armas, Jesús

    Abstract in Spanish:

    OBJETIVO: Describir la tendencia de la mortalidad por picaduras de alacrán en México y sus estados federativos en el período de 1979 a 2003. MÉTODOS: Se estimaron las tasas crudas y estandarizadas de mortalidad por picaduras de alacrán y las tendencias durante el período estudiado a partir de los datos oficiales de mortalidad en México, según la 9.ª y la 10.ª revisiones de la Clasificación Internacional de Enfermedades (códigos E905.2 y X22, respectivamente). Los resultados se estratificaron por grupos de edad. Las frecuencias de muertes por picaduras de alacrán se compararon mediante el riesgo relativo (RR) y sus intervalos de confianza de 95% (IC95%). RESULTADOS: Entre 1979 y 2003, en México se registraron 6 077 muertes por picaduras de alacrán. Se observó una tendencia descendente estadísticamente significativa en la mortalidad estandarizada (beta = -0,195; P < 0,001), con una reducción total de 86,5% entre los períodos 1979-1982 y 2001-2003. La mayor mortalidad en el trienio 2001-2003 se observó en varones (0,81 por 1 000 000 de habitantes) y en los menores de 1 año (7,07 por 1 000 000 de habitantes), seguidos por los grupos de 1 a 4 años (3,78 por 1 000 000 de habitantes) y de 60 años o más (0,84 por 1 000 000 de habitantes). Las poblaciones con menos de 2 500 habitantes presentaron una mortalidad por picaduras de alacrán superior en 11,8 (IC95%: 7,86 a 17,72) veces la observada en las de más de 20 000 habitantes. Los estados con mayor mortalidad por picaduras de alacrán se encuentran en la región occidental y central del país. CONCLUSIONES: A pesar de la sostenida tendencia descendente en el número de muertes por picaduras de alacrán en los últimos 20 años en México, este sigue siendo un importante problema de salud pública. Los grupos de edad más afectados son los niños menores de 5 años y los ancianos. Se deben tomar medidas para que en todas las comunidades, principalmente en las pequeñas, se disponga de los recursos y la información adecuados para la atención oportuna de las personas que sufren una picadura de alacrán.

    Abstract in English:

    OBJECTIVE: To describe the trends in mortality from scorpion stings in Mexico as a whole and in each of its states for the period of 1979 to 2003. METHODS: We estimated the crude and standardized mortality rates due to scorpion stings and the trends during the period studied based on official mortality data for Mexico, using the codes (E905.2 and X22, respectively) from the 9th and 10th editions of the International Classification of Diseases. The results were stratified by age group. The frequencies of deaths from scorpion stings were compared using relative risk (RR), with 95% confidence intervals (CIs). RESULTS: Between 1979 and 2003 in Mexico, 6 077 deaths from scorpion stings were registered. A statistically significant downward trend was found in standardized mortality rates (beta = -0.195; P < 0.001), with a total reduction of 86.5% for the period of 2001-2003 versus 1979-1982. For the 2001-2003 period, the highest mortality rates were in children under 1 year of age (7.07 per 1 000 000), children 1 to 4 years old (3.78 per 1 000 000), persons 60 and older (0.84 per 1 000 000), and males (0.81 per 1 000 000). Persons in communities with fewer than 2 500 inhabitants had a relative risk that was 11.8 times (95% CI: 7.86 to 17.72) that found in communities with more than 20 000 inhabitants. The states with the highest mortality rates were in the central and western regions of the country. CONCLUSIONS: Despite the sustained decline in the number of deaths from scorpion stings in the last 20 years in Mexico, there is still an important public health problem. The groups that are most affected are children under 5 and the elderly. Measures should be taken so that in all communities, especially small ones, adequate resources and information are available to provide for the prompt care of persons who suffer a scorpion sting.
  • Hearing impairment and socioeconomic factors: a population-based survey of an urban locality in southern Brazil Articles

    Béria, Jorge Umberto; Raymann, Beatriz Carmen Warth; Gigante, Luciana Petrucci; Figueiredo, Andréia Cristina Leal; Jotz, Geraldo; Roithman, Renato; Costa, Sady Selaimen da; Garcez, Vera; Scherer, Caroline; Smith, Andrew

    Abstract in Spanish:

    OBJETIVO: Presentar los primeros datos de un estudio de base poblacional sobre sordera y deficiencia auditiva en Brasil. MÉTODOS: Se realizó una encuesta transversal de hogares en 2003 en la que participaron 2 427 personas de 4 años de edad o más. La población de estudio estuvo compuesta por 1 040 hogares escogidos de manera sistemática en 40 sectores censales (conglomerados de viviendas) escogidos al azar en la ciudad de Canoas, estado de Rio Grande do Sul, en el sur de Brasil. Se evaluó la función auditiva de los participantes mediante audiometría tonal liminar y examen físico, según el Protocolo para el Estudio de Trastornos Óticos y Auditivos y las definiciones de niveles auditivos, ambos de la Organización Mundial de la Salud. Entre los datos socioeconómicos colectados estaban los años de escolaridad de las personas estudiadas y los ingresos del jefe del hogar. RESULTADOS: Se encontró que 26,1% de la población estudiada mostró algún grado de deficiencia auditiva y 6,8% (intervalo de confianza de 95% [IC95%]: 5,5% a 8,1%) se clasificó en el grupo con deficiencia auditiva incapacitante. La prevalencia de pérdida auditiva moderada fue de 5,4% (IC95%: 4,4% a 6,4%); de pérdida auditiva grave, 1,2% (IC95%: 0,7% a 1,7%); y de pérdida auditiva profunda, 0,2% (IC95%: 0,03% a 0,33%). Los grupos en mayor riesgo de pérdida auditiva fueron los hombres (razón de posibilidades [odds ratio, OR] = 1,54; IC95%: 1,06 a 2,23); los participantes de 60 años de edad o más (OR = 12,55; IC95%: 8,38 a 18,79); los que tenían menos años de escolaridad formal (OR = 3,92; IC95%: 2,14 a 7,16); y los que tenían menores ingresos (OR = 1,56; IC95%: 1,06 a 2,27). CONCLUSIONES: Estos resultados respaldan las recomendaciones de los planificadores de políticas sanitarias y de los proveedores de servicios de salud sobre la prevención de la sordera y la deficiencia auditiva. Además, pueden contribuir a aumentar el nivel de conciencia de la comunidad, las universidades y las agencias gubernamentales acerca de las necesidades de atención sanitaria que generan los problemas auditivos.

    Abstract in English:

    OBJECTIVE: To provide the first population-based data on deafness and hearing impairment in Brazil. METHODS: In 2003, a cross-sectional household survey was conducted of 2 427 persons 4 years old and over. The study population was composed of 1 040 systematically chosen households in 40 randomly selected census tracts (dwelling clusters) in the city of Canoas, which is in the state of Rio Grande do Sul, in southern Brazil. Hearing function was evaluated in all subjects by both pure-tone audiometry and physical examination, using the World Health Organization Ear and Hearing Disorders Survey Protocol and definitions of hearing levels. The socioeconomic data that were gathered included the amount of schooling of all individuals tested and the income of the head of the household. RESULTS: It was found that 26.1% of the population studied showed some level of hearing impairment, and 6.8% (95% confidence interval (CI) = 5.5%-8.1%) were classified in the disabling hearing impairment group. The prevalence of moderate hearing loss was 5.4% (95% CI = 4.4%-6.4%); for severe hearing loss, 1.2% (95% CI = 0.7%-1.7%); and for profound hearing loss, 0.2% (95% CI = 0.03%-0.33%). The groups at higher risk for hearing loss were men (odds ratio (OR) = 1.54; 95% CI = 1.06-2.23); participants 60 years of age and over (OR = 12.55; 95% CI = 8.38-18.79); those with fewer years of formal schooling (OR = 3.92; 95% CI = 2.14-7.16); and those with lower income (OR = 1.56; 95% CI = 1.06-2.27). CONCLUSIONS: These results support advocacy by health policy planners and care providers for the prevention of deafness and hearing impairment. The findings could help build awareness in the community, in universities, and in government agencies of the health care needs that hearing problems create.
  • Diagnosis of leptospirosis: evaluation of a solid-phase enzyme immunoassay in different stages of the disease Artículos

    Vanasco, Norma B.; Lottersberger, Javier; Schmeling, María F.; Gardner, Ian A.; Tarabla, Héctor D.

    Abstract in Spanish:

    OBJETIVO: Desarrollar un enzimoinmunoensayo en fase sólida (ELISA) para la determinación de inmunoglobulinas G (IgG) (específico de género) y evaluarlo en diferentes etapas de la enfermedad. MÉTODOS: Se analizaron 1 077 muestras séricas de 812 pacientes con sospecha de leptospirosis derivadas al laboratorio del Instituto Nacional de Enfermedades Respiratorias (INER) de la ciudad de Santa Fe, Argentina, entre 1999 y 2005. A partir de un criterio de definición de casos basado en los resultados de la microaglutinación (MAT) y del recuento de leucocitos, y de los valores de neutrofilia, se incluyeron en el estudio 182 casos confirmados (267 muestras), 167 casos negativos (293 muestras) y 40 casos probables (60 muestras). Cada muestra se clasificó según el tiempo de evolución de la enfermedad en tres etapas: primera (< 10 días), segunda (10-25 días) y tercera (> 25 días). En el ELISA, se utilizó como antígeno un extracto de una mezcla de las serovariedades Pyrogenes y Tarassovi cultivadas en medio líquido, tratado con ultrasonidos e inmovilizado por adsorción en placas de poliestireno. Como anticuerpo secundario se empleó un anticuerpo monoclonal de cabra anti-IgG humana conjugado con peroxidasa. El valor de corte, la sensibilidad y la especificidad del ELISA se determinaron utilizando como patrón la definición de casos. Para determinar el valor de corte óptimo se calculó el área bajo la curva de eficacia diagnóstica (curva ROC). RESULTADOS: La sensibilidad de la prueba evaluada aumentó considerablemente en la segunda etapa (93,2%), con respecto a la primera (68,1%), y descendió en la tercera (78,8%). La especificidad aumentó gradualmente desde el 96,3% en la primera etapa hasta el 100% en la tercera. CONCLUSIONES: Los resultados obtenidos indican que esta prueba de ELISA puede ser de gran utilidad como complemento de la MAT para el diagnóstico de la leptospirosis en todas las etapas y, en particular, para adelantar el diagnóstico de la enfermedad aguda.

    Abstract in English:

    OBJECTIVE: To develop a solid-phase enzyme immunoassay (ELISA) for genus-specific immunoglobulin G (IgG) determination with leptospirosis and to evaluate the ELISA in different stages of the disease. METHODS: A total of 1 077 serum samples from 812 patients with suspected leptospirosis were analyzed. The samples had come from diagnoses done in the laboratory of the National Institute of Respiratory Diseases (Instituto Nacional de Enfermedades Respiratorias), in the city of Santa Fe, Argentina, between 1999 and 2005. Included in the study were 182 confirmed cases (267 samples), 167 negative cases (293 samples), and 40 probable cases (60 samples) (based on case definitions based on the results from the microscopic agglutination test (MAT), leukocyte counts, and neutrophilia values). Each sample was classified, according to the days of the natural history of disease, into one of three stages: first (< 10 days), second (10-25 days), or third (> 25 days). The antigen used in the ELISA was an extract of a mixture of pyrogenes and tarassovi serovars cultivated in a liquid medium, treated with ultrasound, and immobilized by adsorption on polystyrene plates. As a secondary antibody, a peroxidase-conjugated goat anti-human IgG monoclonal antibody was used. The cutoff value, sensitivity, and specificity of the ELISA were determined using the definitions of confirmed cases and of negatives cases as the standard. In order to determine the optimal cutoff value, the area under the receiver operating characteristic curve was calculated. RESULTS: The sensitivity of the evaluated test was much higher in the second stage (93.2%) than in either the first stage (68.1%) or the third stage (78.8%). The specificity increased gradually from 96.3% in the first stage to 100% in the third stage. CONCLUSIONS: Our results indicate that this ELISA test can be a very useful complement to the MAT for the diagnosis of leptospirosis in all the stages and, in particular, in order to diagnose acute disease sooner.
  • Obstetric care and severe pregnancy complications in Latin America and the Caribbean: an analysis of information from demographic health surveys

    Souza, João Paulo; Parpinelli, Mary Angela; Amaral, Eliana; Cecatti, Jose Guilherme

    Abstract in Portuguese:

    OBJETIVOS: Compilar, consolidar e analisar as informações obtidas por inquéritos do projeto MEASURE DHS acerca de assistência obstétrica e complicações da gestação na América Latina e Caribe. MÉTODOS: O presente estudo exploratório incluiu sete inquéritos demográficos realizados na década de 1990 (Bolívia, Brasil, Colômbia, Guatemala, Nicarágua, Peru e República Dominicana). Além do levantamento das características das entrevistadas e da assistência obstétrica recebida, foi estimada a ocorrência de complicações (trabalho de parto prolongado e complicações hemorrágicas, hipertensivas e infecciosas). RESULTADOS: A mediana do número de visitas de pré-natal oscilou entre 4,7 (Bolívia) e 6,6 (República Dominicana). Na Bolívia, Peru e Guatemala foram observadas altas taxas (>40%) de assistência ao parto por parteiras tradicionais, parentes e outras pessoas sem treinamento formal. República Dominicana e Brasil apresentaram as maiores taxas de parto em estabelecimento de saúde (>90%). Na Guatemala, Peru e Bolívia, mais de 45% dos partos foram domiciliares. A maior taxa de cesárea foi registrada no Brasil (36,4%); as menores taxas foram registradas no Peru e Guatemala (<12%). A taxa de complicações da gestação referidas pelas mulheres foi de 16,7% no Brasil, 17,9% na Guatemala, 42,1% na Colômbia, 42,5% na Nicarágua, 43,0% na República Dominicana, 51,7% na Bolívia e 51,8% no Peru. CONCLUSÃO: A ocorrência relatada de complicações graves da gestação nos inquéritos avaliados está muito acima da taxa de 15% citada na literatura, podendo ter sido superestimada. A validação prévia dos questionários utilizados para coleta de dados nesse tipo de estudo é extremamente importante para gerar dados mais adequados.

    Abstract in English:

    OBJECTIVE: To compile, consolidate, and analyze information obtained in surveys conducted by the MEASURE DHS [Demographic and Health Surveys] program, concerning obstetric care and pregnancy complications for women in Latin America and the Caribbean, in the five years before the survey. METHODS: This exploratory study utilized data from demographic surveys carried out in the 1990s in seven countries of Latin America: Bolivia, Brazil, Colombia, the Dominican Republic, Guatemala, Nicaragua, and Peru. The study describes the characteristics of the women who were interviewed and of the obstetric care that they received in the five years before the respective survey, and it also estimates the occurrence of prolonged labor and of hemorrhagic, hypertensive, and infectious complications in those five years. RESULTS: The median number of prenatal consultations ranged from 4.7 in Bolivia to 6.6 in the Dominican Republic. More than 40% of deliveries in Guatemala, Peru, and Bolivia were attended by traditional midwives, relatives, or other persons without formal training. The highest rates of deliveries performed in health care facilities (> 90%) were in the Dominican Republic and Brazil. In Guatemala, Peru, and Bolivia more than 45% of deliveries were at home. The highest rate of cesarean delivery was in Brazil (36.4%), and the lowest rates (< 12%) were in Peru and Guatemala. The rate of pregnancy complications reported by the women surveyed was 16.7% in Brazil, 17.9% in Guatemala, 42.1% in Colombia, 42.5% in Nicaragua, 43.0% in the Dominican Republic, 51.7% in Bolivia, and 51.8% in Peru. CONCLUSION: The reported occurrence of severe pregnancy complications in the surveys we examined was well above the 15% rate reported in other scientific literature, suggesting that these complications may have been overestimated in the MEASURE DHS surveys. Prior validation of the questionnaires used for data collection is extremely important in the generation of high-quality data.
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Organización Panamericana de la Salud Washington - Washington - United States
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