Evaluación retrospectiva de la vigilancia de Streptococcus pneumoniae causante de enfermedades invasoras en adultos de la Región Metropolitana-Chile: 2000-2006 / Retrospective assessment of laboratory surveillance for invasive Streptococcus pneumoniae isolates from adults of the Metropolitan Region (Chile): 2000-2006

Este estudio evaluó el funcionamiento de la norma nacional de vigilancia de Streptococcus pneumoniae recuperado desde procesos invasores en adultos de la Región Metropolitana-Chile. Material y Métodos: Se revisaron las notificaciones correspondientes a pacientes de 15 años o más, recibidas por el ISP en el período 2000-2006, emitidas por establecimientos asistenciales de la región. Paralelamente, se revisaron los resultados de cultivos de fluidos estériles practicados en 14 hospitales estatales que atienden adultos. Resultados: Se encontró documentación de 1.429 aislados de S. pneumoniae provenientes de procesos invasores en pacientes de 15 años o más, incluyendo 1.095 notificados y 334 no notificados. La tasa de sub-notificación estimada para los 14 establecimientos visitados alcanzó a 33 por ciento. La edad y el diagnóstico fueron omitidos en 23 y 78 por ciento de las notificaciones, respectivamente. En 235 de 303 (78 por ciento) cepas aisladas de pacientes de 65 años o más, investigadas mediante reacción de Quellung, se identificaron serotipos capsulares representados en la vacuna polisácarida 23-valente. Conclusiones: El Ministerio de Salud anunció un programa de inmunización con vacuna neumocóccica 23-valente dirigido a los adultos mayores. Con miras a la futura evaluación del impacto de esta medida, los resultados de esta revisión señalan la necesidad de reforzar el cumplimento y la calidad de las notificaciones de S. pneumoniae causante de enfermedades in-vasoras.

This study assessed the performance of the national norm for laboratory surveillance of invasive Streptococcus pneumoniae in adults of the Metropolitan Region (Chile). Material and Methods. We reviewed all notifications of isolates from patients > 15 years of age received by the Institute of Public Health of Chile during the period 2000-2006, submitted by health care facilities of the study region. We also reviewed the original records of sterile fluid cultures, in 14 public adult hospitals. Results. We found documentation of 1429 invasive S. pneumoniae isolates recovered from adult patients, including 1095 reported and 334 not-reported isolates. A 33 percent under-reporting rate was estimated for the 14 hospitals where local laboratory records were inspected. Age and clinical diagnosis were omitted in 23 percent and 78 percent of the notifications, respectively. Among 303 isolates from patients > 65 years of age that were investigated with Quellung reaction, 235 (78 percent) had capsular serotypes represented in the 23-valent polysacharide vaccine. Conclusions. The Ministry of Health of Chile announced implementation of 23-valent vaccine immunization program for the elderly. In the perspective of future evaluations of the impact of this intervention, the results of this study indicate the need of reinforcing adherence and improving the quality of notifications of invasive S. pneumoniae.

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

Multirresistencia antimicrobiana en cepas de shigella sp en una comuna semi rural del área norte de Santiago / Antimicrobial multiresistance of shigella sp strains in a semi rural community of north Santiago

Appropriate antimicrobial therapy shortens the duration of Shigellosis and significantly reduces the risk of transmission. Shigella strains resistant to common antimicrobials have increased during the past years, determining the need for a periodic surveillance, to guide effective therapy. Aim: To report the results of a surveillance program in a rural community near Santiago (Colina), for Shigella infections. Material and methods: Between 1995 and 1997, stool samples from 3,534 episodes of diarrhoea, that occurred in Colina, were obtained. Two hundred twenty six Shigella strains were isolated and studied for susceptibility to ampicilin (AM), amoxicillin/clavulanic acid (AMC), cotrimoxazole (STX), chloramphenicol (CAF), tetracycline (TET), furazolidine (FU), ciprofloxacine (CIPR), nalidixic acid (AC NAL), gentamycin (GENT) and cefotaxime (CFTX). Results: Shigella flexnerii represented 134 of 226 Shigella strains isolated. All strains were susceptible to CIPR, AC NAL, GENT and CFTX. Yearly variation of resistance patterns to other antimicrobials were observed for these strains. Resistance to AM varied from 56 to 76 percent, to AMC from 25 to 56 percent, to STX from 21 to 47 percent, to CAF from 36 to 39 percent, to TET from 44 to 78 percent and to FU from 9 to 18 percent. Overall resistance was higher during 1997. All 85 strains of S sonnei were susceptible to CIPR, AC NAL and CFTX. Resistance throughout the years varied from 56 to 88 percent for AM, from 0 to 28 percent for AMC, from 44 to 53 percent for STX, from 11 to 40 percent for CAF, from 11 to 42 percent for TET and from 5 to 11 percent for FU. Overall resistance was also higher during 1997, except for AM and STX. Seven S boydii strains were isolated, only during 1995. All seven were resistant to AM and TET and none were resistant to FU, CIPR, AC NAL and CFTX. One strain was resistant to AMC, STX and CAF. Conclusions: Antimicrobial resistance patterns of Shigella sp isolated in Colina have increased from 1995 to 1997, specially for commonly used antimicrobials. Resistance remains low for furazolidine and all strains remain susceptible to quinolones