[Outbreaks of acute gastroenteritis in Antofagasta Region, Chile 2010]. / Brote de gastroenteritis aguda en la Región de Antofagasta,Chile: 2010.

Outbreaks of acute gastroenteritis are a public health problem. Norovirus is known as the most common cause (50%). In Chile, immediate notification allows surveillance of these events. We describe an acute gastroenteritis outbreak that occurred in Antofagasta region, between March and April 2010. An observational study was conducted to perform the outbreak investigation. Local residents who met case definition were included. Stool samples, epidemiological surveys and environmental samples were requested. The outbreak began approximately on March 8, 2010 and lasted until April 28 with 31,036 reported cases (rate 54 per 1000 inhabitants). The most affected age group was between 25 and 44 years, and diarrhea was the main symptom (97% of cases). We determined the presence of norovirus genogroup II in clinical and environmental samples. This outbreak was caused by consumption of raw vegetables from La Chimba, which were watered and contaminated with treated sewage containing low concentration of free residual chlorine. Subsequently, the outbreak spread from person to person in a poor sanitary environment.

[Sentry surveillance study of rotavirus gastroenteritis in Chile]. / Resultados de la vigilancia centinela de gastroenteritis por rotavirus en Chile.

UNLABELLED: A sentinel-based outpatient and inpatient surveillance for rotavirus infection has been implemented in Chile. AIM: Update the impact of rotavirus infections in Chile. METHODS: Ambulatory surveillance is performed in 14 centers from 8 Regions and hospital-based surveillance in 8 hospitals from three Regions (V, VIII and Metropolitan). RESULTS: In 2007, 339 stool samples that represented 9.3% of all outpatient cases were studied of which 15% were rotavirus positive. A total of 2.074 children younger than 5 years of age were hospitalized representing 9% of all hospitalizations for this age group. Rotavirus was detected in 13.6% of these cases. CONCLUSIONS: In the current epidemiological situation, rotavirus surveillance needs to be sustained with increased efforts to detect cases in order to avoid underreporting. Serotype/genotype surveillance of rotavirus strains needs to be included in the near future.

Brote de gastroenteritis aguda en la Región de Antofagasta,Chile: 2010 / Outbreaks of acute gastroenteritis in Antofagasta Region: Chile 2010

Outbreaks of acute gastroenteritis are a public health problem. Norovirus is known as the most common cause (50%). In Chile, immediate notification allows surveillance of these events. We describe an acute gastroenteritis outbreak that occurred in Antofagasta region, between March and April 2010. An observational study was conducted to perform the outbreak investigation. Local residents who met case definition were included. Stool samples, epidemiological surveys and environmental samples were requested. The outbreak began approximately on March 8, 2010 and lasted until April 28 with 31,036 reported cases (rate 54 per 1000 inhabitants). The most affected age group was between 25 and 44 years, and diarrhea was the main symptom (97% of cases). We determined the presence of norovirus genogroup II in clinical and environmental samples. This outbreak was caused by consumption of raw vegetables from La Chimba, which were watered and contaminated with treated sewage containing low concentration of free residual chlorine. Subsequently, the outbreak spread from person to person in a poor sanitary environment.

Antecedentes: Los brotes por gastroenteritis aguda constituyen un problema de salud pública. Se conoce al norovirus como la causa más común (50%). En Chile, la vigilancia de estos eventos, se establece mediante la notificación inmediata. Objetivo: Investigar y caracterizar el brote de gastroenteritis aguda ocurrido en la Región de Antofagasta, durante los meses de marzo y abril de 2010. Método: Se efectuó un estudio observacional descriptivo para realizar la investigación de brote. Se incluyó a residentes de la región que cumplían con la definición de caso. Se solicitó muestras de deposición, encuesta epidemiológica y muestras ambientales. Resultados: Se estimó que el brote comenzó el 8 de marzo de 2010 y duró hasta el 28 de abril del mismo año; se notificaron 31. 036 casos (tasa 54 por 1.000 habitantes). El grupo de 25 y 44 años de edad fue el más afectado y la diarrea fue el síntoma predominante (97% de los casos). Se determinó la presencia de norovirus genogrupo II en muestras clínicas y ambientales. Conclusiones: El brote se originó por el consumo crudo de hortalizas que provenían del sector La Chimba, las que fueron regadas y contaminadas con agua servida tratada que contenía baja concentración de cloro libre residual y posteriormente se propagó por transmisión persona-persona, en un ambiente sanitario deficiente.

Resultados de la vigilancia centinela de gastroenteritis por rotavirus en Chile / Sentry surveillance study of rotavirus gastroenteritis in Chile

A sentinel-based outpatient and inpatient surveillance for rotavirus infection has been implemented in Chile. Aim: Update the impact of rotavirus infections in Chile. Methods: Ambulatory surveillance is performed in 14 centers from 8 Regions and hospital-based surveillance in 8 hospitals from three Regions (V, VIII and Metropolitan). Results: In 2007, 339 stool samples that represented 9.3 percent of all outpatient cases were studied of which 15 percent were rotavirus positive. A total of 2.074 children younger than 5 years of age were hospitalized representing 9 percent of all hospitalizations for this age group. Rotavirus was detected in 13.6 percent of these cases. Conclusions: In the current epidemiological situation, rotavirus surveillance needs to be sustained with increased efforts to detect cases in order to avoid underreporting. Serotype/genotype surveillance of rotavirus strains needs to be included in the near future.

En Chile, se realiza la vigilancia de gastroenteritis causadas por rotavirus en niños bajo 5 años a través de centros centinelas ambulatorios y hospitalarios. Objetivo: Conocer la epidemiología de las diarreas por rotavirus y evaluar la carga de morbi-mortalidad. Método: La vigilancia ambulatoria se desarrolla en 14 centros de 8 regiones y la vigilancia hospitalaria se lleva a cabo en 8 hospitales pediátricos de las regiones Vª, VIIIªy RM. Resultados: En 2007, 9,3 por ciento de las consultas por diarrea fue estudiada (339), detectándose rotavirus en 15 por ciento de ellas. Se hospitalizaron por diarrea, 2.074 casos, 9 por ciento del total de las hospitalizaciones en este grupo etario. De estas, 13,6 por ciento fueron por rotavirus. Conclusiones: Dada la situación epidemiológica actual, es importante mantener la vigilancia, ampliar la pesquisa de los casos, aplicar el protocolo de vigilancia establecido y determinar el serotipo/genotipo circulante en el país.

Variaciones geográficas de aislamiento de Aeromonas hydrophila en niños con diarrea aguda infantil y problación sana / Geographic variations of the isolation of aeromonas hydrophila in infants with acute infantile diarrhea and healthy population

Entre los nuevos agentes capaces de producir diarrea aguda se ha descrito la participación de Aeromonas hydrophila. Con objeto de conocer la incidencia e importancia relativa de este potencial enteropatógeno en nuestro medio, estudiamos 285 niños menores de 2 años con síndrome diarreico agudo y 140 niños controles pareados en edad y sexo en 2 ciudades (Santiago y Valparaíso) durante los veranos 1983-84 y 85-86. El aislamiento de Aeromonas hydrophila en pacientes de Valparaíso fue de 5,5% (4/73) en niños con diarrea y 2,3% (1/44) en controles, diferencia estadísticamente no significativa. No hubo aislamiento de este agente en Santiago (0/212). Se efectuó estudio de enterotoxicidad de las cepas aisladas que resultó negativo tanto para enterotoxinas termoestable (ST) mediante modelo de ratón y para enterotoxina termolábil (LT) mediante ELISA. Las variaciones geográficas observadas en el aislamiento de aeromonas en diarrea aguda, puede correlacionarse tal vez con existencia de reservorios acuáticos naturales

Situación epidemiológica de las enfermedades transmitidas por alimentos en Santiago de Chile: período 1999-2000 / Survey of foodborne diseases in the Metropolitan Area of Chile

Background: Foodborne diseases are becoming an important cause of morbidity in Chile. In the Metropolitan Region of Chile, the Environmental Health Service started a surveillance program for foodborne diseases in 1994. In 2000, this program was complemented with an etiologic study of individuals involved in outbreaks. Aim: To report the incidence of foodborne outbreaks in the Metropolitan Region of Chile and its causative agents. Results: One hundred ninety outbreaks of foodborne diseases were reported in 1999 and 260 in 2000. The Southern Metropolitan health service had the higher incidence rates (7.5 in 1999 and 8.2 in 2000). The mean attack rates were 25 percent in both periods, affecting 1248 individuals in 1999 and 1774 in 2000. In 18 percent of outbreaks, a pathogen was identified; the most frequent agents were Salmonella Spp, Staphylococcus aureus and Shigella. In 15 percent of subjects, the cause was histamine or chemical agents. In the rest of the cases, the cause was not identified. The foods with higher risk of causing foodborne diseases were hot prepared dishes, home made goat cheese and meats. Conclusions: The incidence rates of foodborne disease in Metropolitan Area of Chile are high and maybe underestimate, only in a low rate of outbreaks was possible to have samples for etiologic studies. For a better understanding of this problem, timely notification of foodborne diseases must be encouraged and educational campaigns about the proper manipulation of food items must be implemented

Flora cutánea facial aerobia y anaerobia en adolescentes con acné y sanos / Face skin aerobic and anaerobic flora in adolescents with acne and healthy

Con el propósito de establecer diferencias en la flora bacteriana existente a nivel del folículo pilosebáceo de adolescentes con acné se estudiaron 50 pacientes con esta patología y 27 controles pareados por edad y sexo. Se obtuvo desarrollo de propionibacterium acnés en 76 por ciento de los adolescentes con acné y en 51,8 por ciento de controles, diferencias no significativas estadísticamente. En el grupo con acné, el P. acnés se cultivó en abundante cantidad (50 o mas colonias) en un 50 por ciento de los casos, regular cantidad en 42 por ciento, respecto del grupo control el desarrollo fue abundante en 42,8 por ciento y regular en 28,6 por ciento. En relación a flora aerobia, staphylococcus epidermis se aisló en 76,4 por ciento de pacientes con acné y 70,3 por ciento de controles. En la serie de pacientes estudiados observamos diferencia cualitativa respecto a presencia de P. acnés, pero no cuantitativa

Relaciones fenotípicas y moleculares entre cepas de vibrio cholerae 01 aisladas en Chile, Perú y Bolivia: comparación con cepas de reservorios ambientales / Phenotypical and molecular relation between vibrio cholerae 01 strains, isolated in Chile, Perú and Bolivia: comparison with strains from environmental reservoirs

The phenotype, biotype and susceptibility to nine antimicrobials was determined for each isolated strain. Also, the genes of cholera and termolabile toxins were determined using DNA probes and a chromosomal restriction profile was done using HindIII, EcoRI and NotI enzymes. Features studied were similar in the 53 strains isolated from patients. Those isolated from environmental reservoirs had different antimicrobial susceptibility, showing ampicillin resistance and the GT gene was detected in one of 20 strains, compared to clinical samples were it was present in all. Strains isolated from patients and envirinment had similar chromosomal restriction profiles. The chromosomal restriction profile gives an image of bacterial genome and it is a useful and reliable tool for the epidemiological surveillance of cholera

Detección de virus Norwalk y México, dos calicivirus humanos en deposiciones de niños chilenos / Detection of Norwalk and Mexico virus, 2 human calciviruses in feces of chilean children

Background: Human calciviruses (HuCVs) cause diarrhea outbreaks associated with consumption of contaminated food and water. Seroepidemiological studies in developing countries, suggest that HuCVs can cause acute gastroenteritis in children. Aim: To study the presence of Norwalk (NV) and Mexico (MX) virus, two HuCVs, in stools of Chilean children from different settings. Subjects and methods: ELISA tests for NV and MX were performed in 677 stool samples for children aged 0 to 132 years old, with acute diarrhea occurring in day care centers or consulting in outpatient clinics or emergency rooms. We also studied eight samples from children involved in a diarrhea outbreak that occurred in a rural community in 1992. A subset of samples was tested with polymerase chain reactions using different primers. Results: Only one sample from a child with acute diarrhea occurring in a day care center was positive for HuCV by polymerase chain reaction. Three samples from the outbreak were positive by the latter method and by ELISA. The HuCV obtained from the day care center was genetically different from other known HuCV. Conclusions: Despite the high seroprevalence, NV and MX viruses were detected in a very low proportion of Chilean children stools

Correlación clínica bacteriológica del uso de eritromicina tópica, solución al 2, en el tratamineto del acné vulgar / Clinical-bacteriological correlation of topical erythromicyn useful in acne vulgaris

El acné es una patología frecuente en adolescentes cuya patogenia es multifactorial, influyendo factores hormonales y también se ha postulado como importante el rol del propionebacterium acnes tanto en la lesión primaria, el comedón, como en la inflamación folicular. Apoyando esta hipótesis han demostrado ser eficaces en el tratamiento del acné diversos antimicrobianos administrados por vía oral y/o local. En este estudio se evaluó la eficacia clínico-bacteriológica de una solución tópica de eritromicina al 2 por ciento (Abboderm) en acné. De 50 adolescentes ingresados, se analizaron 34 que continuaron en control. Tosdos los pacientes presentaban acné vulgar (comedoniano, pustuloso o quístico) y se les indicó eritromicina tópica 2 veces al día por 10 semanas, efectuando controles clínicos bisemanales y estudio bacteriológico previo, 6a. y 10a. semana La respuesta clínica observada fue excelente o buena (con reducción del 50 por ciento o mas de las lesiones) en el 76,4 por ciento de los pacientes a las 6 semanas de tratamiento. Un paciente fue retirado del estudio por efectos adversos. Se observó buena colrrelación entre la respuesta clínica y la disminución de P. acnes, que estaba presente en abundante o regular cantidad en 73,5 por ciento de los pacientes al inicio y sólo en el 13,0 por ciento a la 10a. semana. La flora aerobia S. epidermidis no mostró variaciones cuali ni cuantitativas

Seroprevalencia y posibles factores de riesgo para virus norwalk en Santiago de Chile / Serological prevalence and possible risk factors for norwalk virus in Santiago, Chile

El virus Norwalk ha sido reconocido como un agente frecuente de diarrea aguda en países desarrollados, especialmente como causal de brotes en adultos. La información disponible en países en desarrollo y en poblaciones pediátricas es reducida. Nuestro objetivo fue evaluar la seroprevalencia para virus Norwalk en habitantes de Santiago, e identificar posibles factores de riesgo. Se evaluaron 291 sueros obtenidos entre los años 1990-1991 de individuos menores de 21 años, estratificados por nivel socioeconómico y edad. Para cada individuo se completó un cuestionario relacionado con variables demográficas, ambientales, de hábitos recreativos y de consumo de alimentos. Los sueros fueron evaluados para anticuerpos anti-virus Norwalk mediante test de ELISA basado en partículas virales recombinantes sintéticas. La seroprevalencia global para virus Norwalk fue de 83 por ciento y el nivel de seroprevalencia fue inversamente proporcional al estrato socioeconómico evaluado (p < 0,001). La seroprevalencia aumentó con la edad (p < 0,001) observándose un aumento significativo de seroprevalencia entre los 3 (47 por ciento) y 4 años (82 por ciento) de edad (p = 0,04). La seroprevalencia fue mayor en: individuos del sexo femenino (p = 0,006) aquellos con antecedente de baño en fuentes de agua dulce (p = 0,048), aquellos que presentaban antecedentes de consumo de mariscos crudos (p = 0,0001), vegetales no cocidos (p < 0,0001), y en aquellos niños con madres con menor nivel de educación (p = 0,009). En Santiago la seroprevalencia para virus Norwalk es alta, la adquisicón de anticuerpos ocurre mayoritariamente antes de los 5 años de edad y está fuertemente asociada al nivel socioeconómico al que pertenece el individuo. El consumo de mariscos y vegetales crudos así como el contacto con fuentes de agua potencialmente contaminadas parecen ser factores significativos de riesgo para esta infección. Estos resultados deben orientar el diseño de nuevos estudios prospectivos destinados a identificar la presencia de virus en individuos pertenecientes a grupos de mayor riesgo

Tipos antigénicos de rotavirus circulantes en niños con diarrea aguda en Santiago de Chile / Antigenic types of rotavirus circulanting in children with acute diarrhea in Santiago, Chile

Protective immunity against rotavirus infection is directed against antigenic epitopes on the outer capsid proteins VP7 and VP4. The aim of this study was to characterize the VP7 and VP4 antigenic types circulating in different hospital areas of Santiago, Chile, obtained from children consulting for acute no bloody diarrhea in 5 hospitals representative of the 5 major health areas in Santiago. In addition, 256 rotavirus positive samples, obtained from children with acute diarrhea consulting in the north health area of Santiago between 1985-1987 were studied. All samples were processed for rotavirus by an ELISA and all rotavirus positive samples were selected for VP4 typing by PCR (types P1-P4). A total of 782 rotavirus positive samples were obtained of wich 618 (79 percent) were typeable for one specific VP7 type. VP7 type G1 represented 63 percent of the rotavirus positive samples and predominated in all areas evaluated throughout the entire period of observation. VP7 type G2 represented 13 percent of rotavirus samples, following G1 in predominance. G2 types decreased progressively in all areas in both study periods. G4 types were detected mainly during 1985-1987, and G3 types have so far not been detected. Preliminary analysis of VP4 types suggests that P1 types are predominant and closely associated with VP7 G1 type. These results are relevant for the adoption of appropiate preventive strategies for rotavirus infection, specifically aimed to the development of effective vaccines