Estudio de seroprevalencia de coqueluche en adultos jóvenes, mujeres en puerperio inmediato y sangre del cordón umbilical / Pertussis seroprevalence in adults, post-partum women and umbilical cord blood

La coqueluche es una enfermedad inmunopreve-nible que afecta a todas las edades. Los adultos jóvenes que han perdido su inmunidad contra pertussis son una importante fuente de infección para los lactantes. Ante el aumento sostenido de casos de coqueluche, se plantean nuevas estrategias de prevención.Objetivo. Evaluar la seroprevalencia de coqueluche en donantes de sangre adultos, puérperas y cordones.Métodos. Determinación de títulos de anticuerpos totales anti-Bordetella spp (Bordetella) mediante el ensayo por inmunoabsorción ligado a enzimas. Se evaluaron sueros de 103 donantes, 101 puérperas y 100 cordones. Los títulos < 80 fueron considerados de bajo impacto contra la enfermedad. El pasaje transplacentario de anticuerpos fue evaluado como la relación en los títulos de anticuerpos en cordones/madres. Resultados. Media de edad de los donantes: 28 ± 6 años. Mediana títulos anti-Bordetella: 320; rango intercuartil: 160-320 (RIC); 10% presentaron títulos < 80. Media de edad de las puérperas: 26 ± 6 años. Mediana títulos anti-Bordetella: 160 (RIC: 80320), títulos significativamente menores que las mujeres donantes (p= 0,00002). El 30% de las puérperas presentaron títulos < 80. Mediana anti-Bordetella cordones: 160 (RIC: 80160). Los cordones presentaron títulos < 80 más frecuentemente que sus madres (44% vs. 30%, p= 0,04). El pasaje transplacentario fue 0,83. El título en los cordones fue igual a sus madres en el 54%, menor en el 37% y mayor solo en el 8%.Conclusiones. Los títulos de anticuerpos anti-Bordetella en las puérperas fueron significativamente menores que en las donantes. Las madres y los cordones presentaron títulos < 80 en el 30% y el 44%, respectivamente. Estos datos podrían explicar las altas tasas de ataque en lactantes pequeños que no han completado su esquema de vacunación.(AU)

Situación epidemiológica de coqueluche y estrategias para su control: Argentina, 2002-2011 / Epidemiological situation of pertussis and strategies to control it: Argentina, 2002-2011

Introducción. Coqueluche constituye un problema de salud pública. Objetivos: Describir la morbimortalidad y coberturas de vacunación entre 2002 y 2011, el perfil de los casos de 2011 y las estrategias de control implementadas por el Ministerio de Salud (MSN). Métodos. Estudio descriptivo de vigilancia epidemiológica. Los datos de morbilidad se tomaron del Sistema Nacional de Vigilancia, y los de mortalidad, de la Dirección de Estadística e Información en Salud del MSN y de los informes oficiales de las jurisdicciones. Se utilizó la cobertura administrativa de vacunación a partir de datos provistos por las jurisdicciones al MSN. Se analizó con Epiinfo 7.1.2. Resultados. Entre 2002 y 2011, la notificación de casos de coqueluche y de fallecimientos se incrementó y alcanzó los mayores valores en 2011: tasa de 16 x 100 000 habitantes y 76 fallecidos. Las muertes ocurrieron mayoritariamente en <1 año y las coberturas nacionales de vacunación para 3ra dosis e ingreso escolar fueron >90% y para el primer refuerzo, 80-90%. En 2011, se notificaron 2821 casos confirmados (incidencia 7 x 100 000 hab.): 84% <1 año; 76 fallecidos: 97% <1 año (60,5% <2 meses). Entre las estrategias implementadas, se consolidaron 906 nodos clínicos y 405 de laboratorio; se implementaron la reacción en cadena de la polimerasa como método diagnóstico y la clasificación diferencial de los casos, y se incorporaron dosis adicionales de vacunación. Conclusiones . Entre 2002 y 2011, aumentaron los casos de coqueluche; la mayor morbimortalidad fue en <1 año, con coberturas de vacunación de 80 y 90%. . El mayor número de fallecidos por coqueluche fue en el año 2011. . El MSN fortaleció la vigilancia epidemiológica y orientó las medidas de control.(AU)

Introduction. Pertussis is a challenge for public health. Objectives: To describe pertussis-related morbidity and mortality and immunization coverage for the 2002-2011 period, profile of cases for 2011, and control strategies implemented by the Ministry of Health (MoH) of Argentina. Methods. Descriptive, epidemiological surveillance study. Morbidity data were obtained from the National Health Surveillance System, while mortality data were obtained from the MoHs Health Statistics and Information Department and official jurisdictional reports. Administrative immunization coverage was used based on the data provided by the MoHs jurisdictions. The Epi Info software, version 7.1.2, was used for analysis. Results. The number of reported cases of pertussis increased between 2002 and 2011, reaching its peak in 2011: an incidence of 16 x 100 000 inhabitants, and 76 deaths. Most deaths occurred in infants younger than 1 year old. Immunization coverage achieved at a national level with the third dose and the dose administered at the time of starting primary education was >90%, while the coverage achieved with the first booster dose was 80%-90%. In 2011, 2821 confirmed cases were reported (incidence of 7 x 100 000 inhabitants): 84% in infants <1 year old; 76 deaths: 97% in infants <1 year old (60.5% in infants <2 months old). Among the strategies that were deployed, a total of 906 clinical nodes and 405 laboratory nodes were consolidated; the use of the polymerase chain reaction as a diagnostic method and the differential classification of cases were implemented, and additional vaccine doses were administered. Conclusions . The number of pertussis cases increased between2002 and 2011; the highest morbidity and mortality occurred ininfants younger than 1 year old; immunization coverage reached 80%-90%. . The highest number of pertussis-related deaths was recorded in 2011. . The MoH strengthened the epidemiological surveillance and set guidelines for control measures.(AU)

Pertussis seroprevalence in adults, post-partum women and umbilical cord blood. / Pertussis seroprevalence in adults, post-partum women and umbilical cord blood.

Pertussis is a vaccine-preventable disease that affects people of all ages. Young adults who have lost their immunity to pertussis are the major source of infection in infants. Given the steady increase of pertussis cases, new prevention strategies are required. Objective. To assess pertussis seroprevalence in adult blood donors, post-partum women, and umbilical cords. Metod. Measurement of total titers of anti-Bordetella spp. (Bordetella) antibodies using an enzyme-linked immunosorbent assay. Serum samples from 103 donors, 101 post-partum women and 100 umbilical cords were analyzed. Titers <80 were considered of low impact against the disease. The assessment included transplacental transfer of antibodies and the umbilical cord/maternal ratio of antibody titers. Results. Donors mean age was: 28 ± 6 years old. Mediananti-Bordetella titers: 320; interquartile range (IQR):160-320; 10

had titers <80. Post-partum women mean age was: 26 ± 6 years old. Median anti-Bordetella titers:160 (IQR:80-320), with titers significantly lower than in female donors (p= 0.00002). Titers <80 were found in 30

of post-partum women. Median anti-Bordetella titers in umbilical cords: 160 (IQR: 80-160). Titers <80 were more frequently found in umbilical cords than in mothers (44

versus 30

, p= 0.04). Transplacental transfer was 0.83. Umbilical cord titers were equal to maternal titers in 54

of cases, lower in 37

, and higher only in 8

. Conclusion. Titers of anti-Bordetella antibodies in post-partum women were significantly lower than in female blood donors. Titers <80 were found in 30

of post-partum women and 44

of umbilical cords. These data may account for the high rates of pertussis in young infants who have not yet completed their vaccination schedule.

Epidemiological situation of pertussis and strategies to control it: Argentina, 2002-2011. / Epidemiological situation of pertussis and strategies to control it: Argentina, 2002-2011.

INTRODUCTION: Pertussis is a challenge for public health. OBJECTIVES: To describe pertussis-related morbidity and mortality and immunization coverage for the 2002-2011 period, profile of cases for 2011, and control strategies implemented by the Ministry of Health (MoH) of Argentina. METHODS: Descriptive, epidemiological surveillance study. Morbidity data were obtained from the National Health Surveillance System, while mortality data were obtained from the MoHs Health Statistics and Information Department and official jurisdictional reports. Administrative immunization coverage was used based on the data provided by the MoHs jurisdictions. The Epi Info software, version 7.1.2, was used for analysis. RESULTS: The number of reported cases of pertussis increased between 2002 and 2011, reaching its peak in 2011: an incidence of 16 x 100 000 inhabitants, and 76 deaths. Most deaths occurred in infants younger than 1 year old. Immunization coverage achieved at a national level with the third dose and the dose administered at the time of starting primary education was >90

, while the coverage achieved with the first booster dose was 80

-90

. In 2011, 2821 confirmed cases were reported (incidence of 7 x 100 000 inhabitants): 84

in infants <1 year old; 76 deaths: 97

in infants <1 year old (60.5

in infants <2 months old). Among the strategies that were deployed, a total of 906 clinical nodes and 405 laboratory nodes were consolidated; the use of the polymerase chain reaction as a diagnostic method and the differential classification of cases were implemented, and additional vaccine doses were administered. CONCLUSIONS: The number of pertussis cases increased between 2002 and 2011; the highest morbidity and mortality occurred in infants younger than 1 year old; immunization coverage reached 80

-90

. . The highest number of pertussis-related deaths was recorded in 2011. The MoH strengthened the epidemiological surveillance and set guidelines for control measures.

Incidencia y transmisión de coqueluche en Buenos Aires, Neuquén, Santa Fe y Tucumán: implicancias de las características socio-sanitarias / Incidence and transmission of pertussis in Buenos Aires, Neuquén, Santa Fe and Tucumán: implicancies of social and health characteristics

INTRODUCCION: Pertussis es una enfermedad inmunoprevenible respiratoria que afecta a la población infantil y a los adolescentes/adultos. Para diseñar estrategias que mejoren el control de la enfermedad, resulta esencial profundizar el conocimiento de su epidemiología.OBJETIVO: Estimar la frecuencia de casos de pertussis en 5 provincias argentinas, analizar la implicancia de las características socio-sanitarias de la población e identificar la fuente más probable de contagio.METODOS: Se realizó un trabajo multidisciplinario y multicéntrico empleando algoritmos consensuados. Se estudió a niños menores de 1 año (caso índice, CI) y sus contactos. Para los análisis, se incorporó la información obtenida durante el período a una base de datos ya existente.RESULTADOS: Durante 2006-2011 se analizaron 18.106 muestras de pacientes con sintomatología compatible con pertussis, y se confirmaron 3.766 casos. La mayor proporción de casos confirmados y de casos fatales (8 a 21 por año) se registró en los menores de 1 año. Un análisis de la epidemiología de 113 grupos familiares, constituidos por al menos un CI y dos contactos, determinó que en más del 50% el caso primario no se correspondió al CI. Análisis preliminares mostraron a los convivientes adultos jóvenes como posible fuente de infección de la población vulnerable. En relación con la implicancia de la situación socio-sanitaria en la epidemiología de pertussis, la evolución de los síntomas y la distribución por edades de los casos confirmados mostraron una desigualdad entre los barrios carecientes y los no carecientes.CONCLUSIONES: Se detectó la presencia de más de un caso de pertussis en los grupos familiares. Los adultos jóvenes convivientes serían los responsables de transmitir la infección a los más pequeños. Por la influencia de las condiciones socio-sanitarias en la epidemiología de pertussis, se detectaron patrones diferenciales en la distribución de casos.

INTRODUCTION: Pertussis is an immune preventable resporatory disease affecting the pediatric population and teens/adults. To design better strategies for the disease control, it is essential to improve epidemiological knowledge.OBJECTIVE: To estimate the frequency of pertussis cases in 5 Argentine provinces, to analyze the implication of the socio-economic characteristics and to identify the most likely source of infection.METHODS: A multidisciplinary, multicenter study was conducted, using consensus algorithms. The analysis was focused on children under 1 year (index cases, IC) and their contacts. The information obtained was incorporated into a previous database.RESULTS: 18.106 samples of patients with symptoms compatible with pertussis were analyzed during 2006-2011. Of these cases, 3.766 were confirmed in the lab. The largest proportion of confirmed cases and fatal cases (8-21 per year) were registered in children under 1 year. An epidemiologic analysis of 113 family units, consisting in at least one IC and two contacts, found that in over 50% the primary case did not correspond to the IC. A preliminary analysis showed that the young and adult cohabitants were the possible source of infection for vulnerable populations. Regarding the implications of the socio-sanitary conditions in the disease epidemiology, the evolution of symptoms and the age group distribution of confirmed cases were unequeal between poor and non-poor neighborhoods.CONCLUSIONS: The study detected the presence of more than one case of pertussis in family units. Young and adult cohabitants would be responsible for transmitting the infection to children. Due to the influence of socio-sanitary conditions in the epidemiology of pertussis, differential patterns were detected in the distribution of cases.