[Adherence to immunizations in newborns less than 1500 gr at birth and/or younger than 32 weeks, in two chilean centers]. / Adherencia a las inmunizaciones en niños nacidos con menos de 1.500 gr de peso o antes de 32 semanas de gestación, en dos centros chilenos.

UNLABELLED: Preterm neonates less than 1500 gr. or younger than 32 weeks have an increased morbidity and mortality due to infectious diseases. Immunization of these children is critical but is often incomplete and delayed. OBJECTIVES: To describe the adherence of scheduled and additional vaccines recommended in preterms less than 1500 gr. and to compare the level of compliance in two centers. PATIENTS AND METHODS: Prematures less than 1500 gr. born between January 2006 and December 2008 in a private center (HCPUC) and in a public health system (HSR) were included. Neonatal charts and follow up records were reviewed. Demographic data, diagnosis, scheduled vaccines, delays and its causes, prescription of additional vaccines were registered. RESULTS: 92 children were included in HCPUC and 246 in HSR. Among these 60-70% respectively had delayed immunizations. The reasons for these were considered not justified in almost 80% of the cases, being the primary reason oversight or lack of parental time. The use of additional vaccines is still low in both centers. CONCLUSIONS: Vaccination of prematures in Chile requires important improvements; education of healtheare personnel and parents, inclusión of modern computerized records and inclusión of new efficacious and safe vaccines in the regular immunization program with no cost to the patient.

Adherencia a las inmunizaciones en niños nacidos con menos de 1.500 gr de peso o antes de 32 semanas de gestación, en dos centros chilenos / Adherence to immunizations in newborns less than 1500 gr at birth and/or younger than 32 weeks, in two chilean centers

Preterm neonates less than 1500 gr. or younger than 32 weeks have an increased morbidity and mortality due to infectious diseases. Immunization of these children is critical but is often incomplete and delayed. Objectives: To describe the adherence of scheduled and additional vaccines recommended in preterms less than 1500 gr. and to compare the level of compliance in two centers. Patients and Methods: Prematures less than 1500 gr. born between January 2006 and December 2008 in a private center (HCPUC) and in a public health system (HSR) were included. Neonatal charts and follow up records were reviewed. Demographic data, diagnosis, scheduled vaccines, delays and its causes, prescription of additional vaccines were registered. Results: 92 children were included in HCPUC and 246 in HSR. Among these 60-70 percent respectively had delayed immunizations. The reasons for these were considered not justified in almost 80 percent of the cases, being the primary reason oversight or lack of parental time. The use of additional vaccines is still low in both centers. Conclusions: Vaccination of prematures in Chile requires important improvements; education of healtheare personnel and parents, inclusión of modern computerized records and inclusión of new efficacious and safe vaccines in the regular immunization program with no cost to the patient.

Los niños prematuros menores de 1.500 gr o de 32 semanas de gestación al nacer (RNMBPN) tienen mayor morbimortalidad por enfermedades infecciosas. La vacunación de estos niños es una medida esencial, la que, sin embargo, es subóptima. Objetivo. Describir la adherencia a las vacunas programáticas (PNI) y adicionales recomendadas en RNMBPN en dos centros y comparar su nivel de cumplimiento. Pacientes y Métodos. Se incluyeron RNMBPN nacidos entre enero 2006 y diciembre 2008 de un centro privado (HCPUC) y otro del sistema público (HSR). Se registraron a partir de fichas neonatales y de consultorio de seguimiento, datos demográficos, diagnósticos, vacunas PNI, retrasos y causas de éstos y prescripción de vacunas adicionales. Resultados. Se describen 92 niños en el HCPUC y 246 en el HSR, 60 y 70 por ciento respectivamente tienen alguna vacuna atrasada. En ambos centros las razones fueron no justificadas en 80 por ciento de los casos, siendo la razón principal olvido o falta de tiempo de los padres. El uso de vacunas adicionales es aún escaso en ambos centros. Conclusiones. La vacunación del prematuro en nuestro país requiere mejorías que incluyan educación del personal de salud y padres, mejoras en los registros e incorporación al programa de nuevas vacunas eficaces y seguras sin costo para los pacientes.

[Clinical characteristics of respiratory infection due to Mycoplasma pneumoniae in hospitalized children]. / Características clínicas de la enfermedad respiratoria causada por Mycoplasma pneumoniae en niños hospitalizados.

INTRODUCTION: Studies on Mycoplasma pneumoniae infection are scarce in Chile. OBJECTIVE: To describe clinical characteristics associated with M. pneumoniae in children requiring hospitalization. MATERIAL AND METHODS: All children with a respiratory infection requiring hospitalizations between 2000-2005, whom had a M. pneumoniae specific IgM > or = 1:32, were analyzed. RESULTS: Fifty children meeting study criteria were identified with an average length of hospitalization of 4 days (range: 1-10); mean age was 5.4 years (46% were younger than 5 years). Common clinical features were cough (92%), fever (82%), malaise (74%) and respiratory distress (72%). At admission 40/45 children had hypoxemia. Chest-X ray showed interstitial pattern (69.3%), consolidation (51%) and hyperinsuflation (28.5%). Six patients had pleural effusion. Eighty four percent of patients had a favorable clinical outcome; eight children required admission to the PICU all of whom recovered. CONCLUSION: Respiratory infections associated with M. pneumoniae in our series of children had a highly variable and non-specific clinical spectrum. Chest-X rays showed different pattern in concordance with previous publications.

Características clínicas de la enfermedad respiratoria causada por Mycoplasma pneumoniae en niños hospitalizados / Clinical characterizes of respiratory infection due to Mycoplasma pneumoniae in hospitalized children

Introduction: Studies onMycoplasmapneumoniae infection are scarce in Chile. Objective: To describe clinical characteristics associated withM. pneumoniae in children requiring hospitalization. Material and Methods: All children with a respiratory infection requiring hospitalizations between 2000-2005, whom had aM. pneumoniae specific IgM ≥ 1:32, were analyzed. Results: Fifty children meeting study criteria were identified with an ave-rage length of hospitalization of 4 days (range: 1-10); mean age was 5.4 years (46 percent were younger than 5 years). Common clinical features were cough (92 percent), fever (82 percent), malaise (74 percent) and respiratory distress (72 percent). At admission 40/45 children had hypoxemia. Chest-X ray showed interstitial pattern (69.3 percent), consolidation (51 percent) and hyperinsuflation (28.5 percent). Six patients had pleural effusion. Eighty four percent of patients had a favorable clinical outcome; eight children required admission to the PICU all of whom recovered. Conclusión: Respiratory infections associated withM. pneumoniae in our series of children had a highly variable and non-specific clinical spectrum. Chest-X rays showed different pattern in concordance with previous publications.

Introducción: La infección por Mycoplasma pneumoniae es una condición respiratoria poco estudiada en nuestro medio. Objetivo: Describir las características clínicas de los niños hospitalizados porM. pneumoniae. Materiales y Métodos: Se analizaron todos los pacientes hospitalizados por infecciones respiratorias durante el 2000-2005, con IgM específica; se utilizó como diagnóstico de enfermedad por M. pneumoniae la presencia de fluorescencia verde manzana 2 a 3 positivo en títulos ≥ 1:32 diluciones. Resultados: Se analizaron 50 hospitalizaciones, con estadía promedio de 4 días (rango: 1-10); la edad promedio fue 5,4 años (46 por ciento bajo 5 años). Los síntomas más frecuentes fueron tos (92 por ciento), fiebre (82 por ciento), compromiso del estado general (74 por ciento) y dificultad respiratoria (72 por ciento). Al momento del ingreso 40/45 presentaron hipoxemia. La radiografía de tórax (RT) reveló infiltrado intersticial (69,3 por ciento), foco de consolidación (51 por ciento) e hi-perinsuflación (28,5 por ciento). Seis presentaron efusión pleural asociada. En 84 por ciento la evolución fue favorable; sin embargo, 8 niños ingresaron a la Unidad de Paciente Critico para monitorización. No hubo decesos Conclusiones: La infección respiratoria asociada aM. pneumoniae en niños produjo manifestaciones inespecíficas y variables de un caso a otro. La RT reveló una variedad de presentaciones similar a lo mostrado en la literatura médica.

[Invasive pneumococcal disease and consolidated pneumonia in infants: one year of surveillance in three Chilean health care centers]. / Infección neumocóccica invasora y neumonía consolidante en lactantes: Un año de vigilancia en tres centros hospitalarios chilenos.

OBJECTIVE: To describe frequency and type of invasive pneumococcal diseases (IPD) and consolidated pneumonia (CP) in Chilean infants. PATIENTS AND METHODS: One-year prospective surveillance in three health care centers. PID surveillance: blood culture in infants with suspected invasive bacterial disease or with fever higher than 39 degrees C axillary without focus or with acute otitis media. CP surveillance: blood culture and independent evaluation of chest X-ray in infants with suspected pneumonia. RESULTS: IPD: in 4,369 infants studied, 58 cases of invasive bacterial diseases were identified, 37 (64%) due to S. pneumoniae. Rates of IPD: 110/100,000 (Chilian) and 288/100,000 (Valparaiso). Serotypes identified: 18C(n: 8), 14 (n: 8), 19A(n: 5), others (n: 12). CP: in 3,005 infants 762 CP were detected. Rates of CP: 2,918/100,000 (Chilian) and 5,547/100,000 (Valparaiso). DISCUSSION: Results support the relevance of S. pneumoniae as the main cause of invasive bacterial disease and the high frequency of CP in this age group in Chile.

Infección neumocóccica invasora y neumonía consolidante en lactantes: Un año de vigilancia en tres centros hospitalarios chilenos / Invasive pneumococcal disease and consolidated pneumonia in infants: One year of surveillance in three Chilean health care centers

Objetivo: Describir la frecuencia y tipo de enfermedad neumocóccica invasora (ENI) y neumonía consolidante (NC) en lactantes chilenos. Pacientes y Métodos: Vigilancia prospectiva durante un año en tres centros. Vigilancia de ENI: hemocultivo en lactantes con sospecha clínica de enfermedad bacteriana invasora (EBI) o fiebre > 39 °C axilar, sin foco o con otitis media aguda. Vigilancia de NC: hemocultivo y evaluación independiente de la radiografía en lactantes con sospecha clínica de neumonía. Resultados: ENI: en 4.369 lactantes enrolados se detectaron 58 casos de EBI, 37 (64 por ciento) por Streptococcus pneumoniae. Tasas de ENI: 110/100.000 (Chillan) y 288/100.000 (Valparaíso). Serotipos de S. pneumoniae identificados: 18C (n: 8), 14 (n: 8), 19A (n: 5), otros (n: 12). NC: en 3.005 niños enrolados se detectaron 762 NC. Tasas de NC: 2.918/ 100.000 (Chillan) y 5.547/100.000 (Valparaíso). Discusión: Se confirma la relevancia de S. pneumoniae como agente de EBI así como la elevada frecuencia de NC en lactantes en Chile.

Objective: To describe frequency and type of invasive pneumococcal diseases (IPD) and consolidated pneumonia (CP) in Chilean infants. Patients and Methods: One-year prospective surveillance in three health care centers. PID surveillance: blood culture in infants with suspected invasive bacterial disease or with fever higher than 39°C axillary without focus or with acute otitis media. CP surveillance: blood culture and independent evaluation of chest X-ray in infants with suspected pneumonia. Results: IPD: in 4,369 infants studied, 58 cases of invasive bacterial diseases were identified, 37 (64 percent) due to S. pneumoniae. Rates of IPD: 110/100,000 (Chilian) and 288/100,000 (Valparaiso). Serotypes identified: 18C(n: 8), 14 (n: 8), 19A(n: 5), others (n: 12). CP: in 3,005 infants 762 CP were detected. Rates of CP: 2,918/100,000 (Chilian) and 5,547/100,000 (Valparaiso). Discussion: Results support the relevance of S. pneumoniae as the main cause of invasive bacterial disease and the high frequency of CP in this age group in Chile.

Adherencia a las inmunizaciones en niños con necesidades de cuidado médico especial / Adherence to immunization among children with special health care needs

Los niños con necesidades de cuidado médico especial (NECMES) son una población creciente en pediatría y su riesgo de complicaciones asociadas a enfermedades infecciosas es alto. Objetivo. En niños con NECMES, describir la adherencia al Programa Nacional de Inmunizaciones (PNI) y al uso de vacunas adicionales recomendadas. Pacientes y Métodos. En forma retrospectiva se registró en niños con NECMES, hospitalizados: vacunas PNI administradas, retrasos y causas de éstos, prescripción y administración de vacunas adicionales. Resultados. Se analizaron 70 niños: 30 presentaron al menos un atraso en las vacunas PNI, 40,0 por ciento por hospitalizaciones previas, 26,7 por ciento por morbilidad menor y 20 por ciento por otras causas no justificadas. Se prescribió vacunas adicionales al PNI a 49 niños (70 por ciento) pero sólo 25 las recibieron. Conclusiones. Esta población presentó baja adherencia al esquema de vacunación PNI y extra PNI. Cualquier contacto con el personal de salud, incluyendo la hospitalización, debe constituir una oportunidad para actualizar las inmunizaciones.

The proportion of children with special health care needs (CSHCN) due to chronic illness is increasing. They have a high risk of complications due to infectious diseases. Objective. To describe adherence to the Expanded Program of Immunization (EPI) and administration of other expert recommended vaccines in CSHCN. Patients and methods. In a retrospective manner information on chronic disease, EPI vaccines administration, reasons for delays, prescription and administration of additionally recommended vaccines was registered in a cohort of hospitalized CSHCN. Results. Seventy children were analyzed. Thirty (42.9 percent) had at least one delay in EPI immunization schedule; 40 percent due to previous hospitalizations, 26.7 percent due to minor morbidity and 20 percent due to other unjustified reasons. Forty-nine (70.0 percent) received prescriptions for additional vaccines, but only 25 actually received them. Conclusions. CSHCN showed low adherence to EPI and received few additionally recommended vaccines. Every contact with these patients, including hospitalization should be used to update immunizations.

[Clinical and epidemiological manifestations of parainfluenza infection in hospitalized children]. / Características clínicas y epidemiológicas de la infección por virus parainfluenza en niños hospitalizados.

BACKGROUND: Human parainfluenza viruses (hPIV) are a common cause of respiratory illness of children but published data on clinical characteristics of hPIV infection in South America is scarce. OBJECTIVE: To review the clinical presentation and epidemiological features of hPIV in a series of hospitalized children in Chile. PATIENTS AND METHODS: Retrospective review of clinical charts from all pediatric admissions with a diagnosis of respiratory disease (between January 2001 to December 2004) at the Catholic University Hospital, Santiago, Chile. Nasopharyngeal secretions were tested for hPIV in children admitted with suspected respiratory viral infections. RESULTS: A total of 3,043 respiratory admissions were recorded during the study period; 64 children (2.1%) were hPIV positive. Average age was 13 months (range: lm to 12y) and 77%> were younger than 2 years. HPIV-2 was the most common type identified (47%). A seasonal trend was noted for serotypes hPIV-2 and 3. Acute wheezing (40%o) and pneumonia (30%) were the most common clinical diagnosis in hPIV positive children and 17%> hPIV positive children (44%> for hPIV-1) were associated with laryngitis. All hPIV positive bronchiolitis were due to serotypes hPIV-2 and 3. CONCLUSION: hPIV can cause respiratory disease requiring hospitalization; serotypes hPIV-2 and 3 displayed a seasonal trend. Although hPIV is an uncommon cause of severe respiratory infecion requiring hospitalization in children, it should be considered in the differential diagnosis of laryngitis, bronchiolitis and pneumonia, especially in younger children.

Características clínicas y epidemiológicas de la infección por virus parainfluenza en niños hospitalizados / Clinical and epidemiological manifestations of parainfluenza infection in hospitalized children

Los virus parainfluenza del ser humano (VPIh) son patógenos importantes de enfermedad respiratoria en niños; pese a ello, existe escasa información publicada en Sudamérica dirigida a caracterizar esta infección. Objetivo: Describir las manifestaciones clínicas y epidemiológicas específicas de los VPIh en niños hospitalizados. Pacientes y Métodos: Se revisaron todas las hospitalizaciones respiratorias (HR) efectuadas en el Hospital de la Pontificia Universidad Católica, Santiago, Chile, durante el período 2001-2004 y sus respectivos estudios virales obtenidos de secreciones nasofaríngeas en aquellos con sospecha de infección viral. Resultados: Se identificaron 3.043 HR siendo 64 (2,1 por ciento) VPUrh La edad promedio fue 13 meses (rango: 1 m-12 a) siendo 77 por ciento) de edad inferior a dos años. VPIh-2 fue el serotipo prevalente (47 por ciento), observándose una tendencia estacional para los serotipos 2 y 3. Las presentaciones más frecuentes fueron sibilancias asociadas a virus (40 por cientoo) y neumonía (30 por ciento). Todas las bronquiolitis se presentaron asociadas a VPIh serotipos 2 y 3. Sólo 17 por ciento de los hospitalizados por VPIh+ (44 por ciento VPIh-1) desarrollaron laringitis. Conclusión: Virus parainfluenza humano puede ser responsable de HR en niños, mostrando una tendencia estacional VPIh-2 y el serotipo 3. Aunque son poco frecuentes como causa de HR, confirmamos su participación como etiología específica de laringitis, bronquiolitis y neumonía, especialmente en niños pequeños.

Background: Human parainfluenza viruses (hPIV) are a common cause of respiratory illness of children but published data on clinical characteristics of hPIV infection in South America is scarce. Objective: To review the clinical presentation and epidemiological features of hPIV in a series of hospitalized children in Chile. Patients and Methods: Retrospective review of clinical charts from all pediatric admissions with a diagnosis of respiratory disease (between January 2001 to December 2004) at the Catholic University Hospital, Santiago, Chile. Nasopharyngeal secretions were tested for hPIV in children admitted with suspected respiratory viral infections. Results: A total of 3,043 respiratory admissions were recorded during the study period; 64 children (2.1 percent) were hPIV positive. Average age was 13 months (range: lm to 12y) and 77 percent> were younger than 2 years. HPIV-2 was the most common type identified (47 percent). A seasonal trend was noted for serotypes hPIV-2 and 3. Acute wheezing (40 percento) and pneumonia (30 percent) were the most common clinical diagnosis in hPIV positive children and 17 percent> hPIV positive children (44 percent> for hPIV-1) were associated with laryngitis. All hPIV positive bronchiolitis were due to serotypes hPIV-2 and 3. Conclusion: hPIV can cause respiratory disease requiring hospitalization; serotypes hPIV-2 and 3 displayed a seasonal trend. Although hPIV is an uncommon cause of severe respiratory infecion requiring hospitalization in children, it should be considered in the differential diagnosis of laryngitis, bronchiolitis and pneumonia, especially in younger children.

[Human metapneumovirus as hospitalization cause in children under 3 years old with acute respiratory infections during 2004]. / Metapneumovirus humano como causa de hospitalización en niños bajo 3 años de edad, con infección respiratoria aguda, durante el año 2004.

Human metapneumovirus was detected in 15 of 123 children (12%) younger than 3 years of age hospitalized for treatment of acute respiratory infection between July and November 2004. The virus was detected by RT-PCR directly from nasopharyngeal swabs and/or from supernatants after cell culture. Children infected with hMPV were mostly younger than one year of age (67%), all presenting with fever and cough. The main cause for hospitalization was the need for oxygen therapy (73%). Four hMPV positive children had an identifiable co-morbid condition but had a similar clinical evolution when compared to previously healthy infants. Chest radiography showed an increase in interstitial infiltrates with focal consolidation in 6 children. Obstructive bronchial syndrome and bronchiolitis, with or without pneumonia, were the most frequent diagnosis associated with hMPV positivity. A rapid and sensitive diagnostic method is required to improve diagnosis and treatment of these patients.

Metapneumovirus humano como causa de hospitalización en niños bajo 3 años de edad, con infección respiratoria aguda, durante el año 2004 / Human metapneumovirus as hospitalization cause in children under 3 years old with acute respiratory infections during 2004

Metapneumovirus humano (MPVh) fue detectado entre julio y noviembre en 15 de 123 niños bajo 3 años de edad hospitalizados por infección respiratoria aguda (12 por ciento). Las muestras fueron estudiadas mediante técnicas de biología molecular (RPC-TR de muestra de hisopado nasofaríngeo y/o de sobrenadante de cultivo). El 67 por ciento de los niños hospitalizados con MPVh tenían menos de 1 año de edad, todos ellos presentaron tos y fiebre y el principal motivo de hospitalización fue el requerimiento de oxígeno en 73 por ciento de los casos. Si bien un tercio de los pacientes tenía patología previa, su evolución clínica no fue diferente respecto de los niños previamente sanos. El patrón radiológico mostró aumento de la trama intersticial, con focos de consolidación en 6 casos (40 por ciento). El diagnóstico más frecuente fue síndrome bronquial obstructivo o bronquiolitis, asociado o no a neumonía. Destaca la necesidad de un método de diagnóstico rápido para optimizar el diagnóstico diferencial, manejo y control de infecciones en estos pacientes.

Human metapneumovirus was detected in 15 of 123 children (12 percent) younger than 3 years of age hospitalized for treatment of acute respiratory infection between July and November 2004. The virus was detected by RT-PCR directly from nasopharyngeal swabs and/or from supernatants after cell culture. Children infected with hMPV were mostly younger than one year of age (67 percent), all presenting with fever and cough. The main cause for hospitalization was the need for oxygen therapy (73 percent). Four hMPV positive children had an identifiable co-morbid condition but had a similar clinical evolution when compared to previously healthy infants. Chest radiography showed an increase in interstitial infiltrates with focal consolidation in 6 children. Obstructive bronchial syndrome and bronchiolitis, with or without pneumonia, were the most frequent diagnosis associated with hMPV positivity. A rapid and sensitive diagnostic method is required to improve diagnosis and treatment of these patients.

Vacunación del niño prematuro: un tema a veces olvidado / Vaccination in premature infants: an issue many times forgotten

Las infecciones bacterianas o virales pueden adquirir mayor gravedad o incluso ser letales en niños prematuros. El retraso de la vacunación en prematuros es frecuente. Esto se debería a falta de claridad sobre la seguridad y respuesta inmune de las vacunas así como a una subestimación de los riesgos de las infecciones en estos niños. No hay evidencia de que la frecuencia de reacciones adversas a vacunas en prematuros sea mayor que en niños de término. Aunque en prematuros extremos la respuesta inmune a vacunas puede ser menor, generalmente es suficiente para una adecuada protección contra infecciones graves. El esquema de inmunización debe ser similar al del niño de término, según edad cronológica. En prematuros debieran considerarse vacunas especiales como anti-neumocócicas conjugadas, anti-influenza. Otras estrategias para proteger a estos niños serían la adherencia rigurosa de los contactos intra domiciliarios al esquema del Programa Ampliado de Inmunizaciones así como el uso de vacunas especiales como la anti-influenza y pertussis acelular en niños mayores y adultos.

Púrpura de Schonlein-Henoch asociado a varicela: Caso clínico / Henoch-Schonlein purpura associated with varicella: A clinical case

Con el objeto de discutir el rol de la infección por virus varicela zóster (VVZ) como desencadenante inhabitual de Púrpura de Schonlein-Henoch (PSH) se comunica el caso de una paciente de 4 años, con PSH y varicela. La evolución del PSH en esta niña se complica con dolor abdominal intenso, requiriendo terapia esteroidal sistémica. Al quinto día de iniciado el púrpura aparece un exantema vesicular (confirmado como VVZ mediante inmunofluorescencia directa de fluido vesicular). Se agrega Aciclovir endovenoso en forma empírica, dado el riesgo de evolución grave de la infección por VVZ durante el curso de una terapia esteroidal sistémica. Ambas patologías tuvieron una resolución favorable.

Inmunogenicidad y reactogenicidad de una vacuna de difteria, tétanos, pertussis acelular de contenido antigénico reducido, dTpa, en niños de 10 a 11 años de edad y en adultos / Immunogenicity and reactogenicity of a reduced antigen content diphteria, tetanus, acellular pertussis vaccine, dTpa, in 10 to 11 years old children and in adults

Background: New vaccination strategies are needed to control the increasing problem of pertussis in teenagers and adults. Aim: To determine the immunogenicity and reactogenicity of a diphtheria-tetanus-acellular pertussis (dTpa) vaccine with reduced antigen content. Material and Methods: A single dose of the dTpa vaccine was administered to 60 children 10 to 11 years old and 60 healthy adults. At the moment of vaccination and one month later, antibody levels were measured against 3 B pertussis antigens: anti-pertussis toxin (PT), anti-pertactin (PRN) and anti-filamentous hemagglutinin (FHA), as well as anti-tetanus and anti-diphtheria antibodies. Local and general symptoms were registered during 14 days following vaccine administration. Results: Antibody response for PT, FHA and PRN was 98.3 percent, 100 percent and 100 percent in adults and 98.2 percent, 100 percent and 98.2 percent in children. Seropositivity for all pertussis antigens was 100 percent in adults and in children one month after vaccination. Geometric mean titers (GMT) significantly increased in adults and children. The seroprotection level achieved for tetanus and diphtheria antibodies one month after vaccination was 96.7 percent for adults and 100 percent for children, respectively. No serious adverse events were reported during the study. Among local symptoms pain was the most frequent (88-90 percent), but it was mostly mild or moderate. Solicited general symptoms observed for children and adults, respectively, included headache (37 percent and 53 percent), fatigue (18 percent and 35 percent) gastrointestinal symptoms (18 percent and 25 percent) and fever (8 percent and 3 percent). Only one vaccinee had fever above 39­C. Conclusions: the dTpa vaccine showed an adequate safety profile and induced an intense immunological response to all antigens in adults and children aged 10-11

Inmunogenicidad de una vacuna recombinante anti hepatitis B en personal de salud / Immune response to hepatitis B vaccine in health care workers

El virus de hepatitis B (HB) es capaz de persistir en un porcentaje de los infectados produciendo enfermedad hepática crónica a largo plazo. El personal de salud es un grupo especialmente expuesto a contraer esta infección. Actualmente se dispone de vacunas HB inmunogénicas, eficaces y seguras. Aunque la mayoría de las personas responde de una forma adecuada, un porcentaje bajo no son respondedores. Con el objeto de evaluar la respuesta inmune a una vacuna recombinante e identificar potenciales factores de riesgo de una respuesta inadecuada, se realizó un estudio prospectivo en funcionarios de la salud. A los 6 meses de recibir 3 dosis de vacuna contra HB (0-1-6 meses) se les midió título de anticuerpos contra antígeno de superficie de hepatitis B (anti HBs). Se estudiaron 485 sujetos con una relación mujer: hombre de 2.6:1 y una edad promedio de 35.8 años. De los 485, 409 (84.3 por ciento) funcionarios presentaron niveles mayores de 100 mUI/ml, 55 (11.3 por ciento) mostraron niveles entre 10 y 100 mUI/ml y 21 (4.3 por ciento) bajo 10 mUI/ml (4.3 por ciento). Un análisis multivariado de estos 3 grupos mostró que a mayor edad, los niveles de anti HBs eran menores (p< 0.01). No se encontró esta asociación con sexo e índice de masa corporal. Estos resultados muestran una adecuada inmunogenicidad de la vacuna recombinante ya que 95.7 por ciento de los individuos vacunados presentó niveles anti HBs considerados como protectores (> 10 mUI/ml)

Complicaciones en niños con varicela en cuatro hospitales de Santiago-Chile: espectro clínico y estimación de costos directos / Varicella complications requiring hospitalization in four hospitals in Santiago, Chile: clinical spectrum and estimation of direct costs

Background: The knowledge of varicella complications and their associated cost may help for a better evaluation of varicella immunization benefits. Aim: To determine frequency, type, outcome and affected population of varicella complications in children requiring hospitalization, and to estimate their direct costs. Material and methods: Retrospective analysis of medical records of children admitted to four hospitals in Santiago, Chile, due to varicella complications between January 1997 and February 1999. Calculation of direct costs of hospitalizations in a sample of 30 patients. Results: One hundred fifty four patients were identified, 74 percent were younger than 5 years old, only one was immunocompromised. Complications identified were skin and soft tissue infections in 63 percent, invasive infections in 25,3 percent, neurological in 7.1 percent and miscellaneous in 4,5 percent. Staphylococcus aureus and Group A ß-haemolytic Streptococcus (GABS) were predominantly isolated. S. aureus was the main agent identified in superficial infections and GABS in invasive infections (sterile sites). Two patients died due to invasive infections (streptococcal toxic shock and S. aureus septicaemia) and 11 required surgical procedures. The average cost per hospitalization was US$ 600 in public hospitals and US$ 1,800 in the private hospital. Conclusions: Varicella complications requiring hospitalization are due mainly to bacterial infections and they affect immunocompetent toddlers. These complications can be severe and even fatal

Estado actual de inmunidad para hepatitis por virus A en diversos grupos de adultos / Current state of hepatitis A virus immunity in adults

Background: As sanitary and economic conditions improve, the prevalence of antibodies to hepatitis A is now significantly lower. Aim: To evaluate the prevalence of hepatitis A virus antibodies in healthy Chilean adults. Material and methods: Antibodies to hepatitis A virus were measured, using a commercial ELISA assay, in 215 voluntary blood donors (163 male, aged 19 to 30 years old) and 295 medical students and health personnel (156 male, aged 19 to 39 years old), residing in Valdivia, Chile. Results: Antibodies against hepatitis A virus were found in 68,2 percent of the total sample (351/510). Ninety percent of flood donors and 54 percent of health personnel and students were positive (p <0.01). Age specific prevalence in blood donors 19 to 22, 23 to 29 and 27 to 30 years old was 81,0 percent, 95,2 percent and 95,6 percent respectively. Among the same age groups in medical students, the prevalence was 47,9 percent, 53,2 percent and 61,9 percent respectively (p <0.01). Conclusions: This study indicates a reduction in the prevalence of hepatitis A virus antibodies among adults in Valdivia (Chile). Differences detected between individuals are probably related to different socioeconomic levels. Medical students have an increased risk for hepatitis A infections than the general population

Anticuerpos séricos contra el virus hepatitis A en sujetos de nivel socioeconómico medio y bajo en comunas urbanas de Santiago / Serum antibodies against hepatitis A virus among subjects of medium and low socioeconomic levels in urban Santiago

Background: The epidemiology of hepatitis A virus (HAV) infection is closely associated to the level of hygiene and sanitation of the population. Newly industrialising areas experience a transition from high to intermediate endemicity, which is characterized by a shift in the exposure age to HAV, from early childhood to school ages or adolescence. Aim: To measure the prevalence of HAV antibodies in subjects living in urban Santiago. Subjects and methods: A HAV antibody survey in five medium and low socioeconomic level urban districts of northern Santiago, was conducted in 1996. Healthy subjects aged 1 to 39 years old were recruited from randomly selected households. Results: Five hundred three subjects were studied. Anti HAV antibodies were found in 13.2, 29.5, 59.6, 78.1, 95.6 and 98.2 percent of individuals aged 1 to 4, 5 to 9, 10 to 14, 15 to 19, 20 to 29 and 30 to 39 years old, respectively. Conclusions: The profile of positive antibodies is compatible with an intermediate pattern of transmission of HAV. The current data supports the idea that infection is shifting towards older ages. A progressive increase in the number of susceptible school age children and teenagers is propitious for the occurrence of common source hepatitis A outbreaks