Subject(s)
Humans , Animals , Enterococcus , Enterococcus/classification , Enterococcus/drug effects , Enterococcus/enzymologyABSTRACT
Group A Streptococcal (GAS) infections have increased in frequency and severity worldwide. During April 1996, a nosocomial outbreak associated to GAS infections affected seven patients admitted to a pediatric burn unit. The causative organism was likely disseminated from the source patient to another child in the emergency room before he was transferred to the burn unit. Patients developed burn infections or invasive disease. One of them died due to a toxic shock syndrome and 3 other lost their skin grafts. Perineal and nasal microbiological surveillance of 42 related health care workers identified only one of them as carrier of S pyogenes. Aim: To report a molecular analysis of an apparently clonal outbreak. Material and methods: The available isolates were analyzed by molecular methods including random amplified polymorphic DNA analysis (RAPD) with 4 different primers, Sma-I pulsed field gel electrophoresis (PFGE) analysis, and speA, speB and speC detection by polymerase chain reaction (PCR). Results: Two phylogenetically distant and sequentially isolated bacterial groups were identified either by RAPD analysis with selected primers or by Smal-PFGE analysis. The first group involved isolates identified in two patients that included the lethal case. The second bacterial group comprised 5 clinical isolates and the perineal and nasal isolates obtained from a health care worker. Only strains belonging to the first group harbored the speA gene and were associated with invasive disease. The second group could be split further in two subgroups according to their speB profile. Conclusions: RAPD analysis with selected primers can reproduce the PFGE-discriminating ability on the epidemiological analysis of GAS infections
Subject(s)
Humans , Streptococcus pyogenes , Burn Units , Burns , Streptococcal Infections/epidemiology , Molecular Sequence Data , Disease Outbreaks , Superantigens/isolation & purification , Molecular Probe TechniquesABSTRACT
Chile ha experimentado un cambio epidemiológico en la última década con la desaparición progresiva de la fiebre tifoidea causada mayoritariamente por Salmonella typhi y la emergencia epidémica de Salmonella enteritidis, un agente de diarrea sin tratamiento específico eficaz y ligado estrechamente a productos avícolas contaminados e inadecuadamente preparados. La fiebre tifoidea ha disminuido su importancia debido al desarrollo humano experimentado en Chile que ha significado un alto grado de cobertura de agua potable y de manejo de excretas, en conjunto con un mayor nivel de educación, factores que limitan la contaminación del ambiente por este agente y la adquisición de él por huéspedes susceptibles. A pesar de este notable avance, un nuevo serotipo de salmonela ha irrumpido en Chile, denominado enteritidis, que ha logrado aprovechar el nuevo escenario logrado con la industrialización avícola donde miles de aves ahora conviven en pequeños espacios facilitando la infección cruzada entre ellas. La contaminación intermitente de huevos por vía transovárica o superficial permite la llegada de este agente en forma errática pero persistente al ser humano. Este nuevo escenario y la ausencia de un tratamiento antimicrobiano eficaz para este agente, obligan a que nuestro país adopte nuevas estrategias de prevención que involucran a productores, distribuidores y consumidores de productos avícolas
Subject(s)
Humans , Health Promotion/trends , Salmonella Infections/epidemiology , Natural History of Diseases , Salmonella enteritidis/pathogenicity , Salmonella Infections/prevention & control , Salmonella typhi/pathogenicity , Typhoid Fever/epidemiologyABSTRACT
Background: Salmonella enteritidis (SE) is a frequent cause of diarrhea, and is transmitted mainly by SE contaminated eggs or poultry meat. The frequency of SE contaminated eggs or chicken meat and the risk for acquiring this pathogen is unknown in Chile. Aim: To measure SE contamination in eggs poultry meat and entrails offered in retail markets in the Metropolitan Area during two consecutive years (1998-1999). Material and methods: Samples were placed in sterile bags and transported to the laboratory before 4 hours at 4C. Microbiologic detection was done using a standard procedure and an immunodetection assay. Results: SE was found in one of 1081 egg samples (0.09 percent). The contaminated sample was offered in a supermarket under their own commercial name. Six percent of 1154 poultry meat samples were contaminated by SE and 2.3 percent by other Salmonella serotypes. Entrails had even higher rates with 10.2 percent of 370 samples harboring SE and 2,7 percent other serotypes. Total Salmonella sp. isolates and SE isolates declined during 1999. Nine SE phagotypes were identified, predominating types 4 and 7. Conclusions: Eggs and other avian products are contaminated by different SE phagotypes and other Salmonella serotypes, implicating a risk for the consumers