Phenotypical and genotypical characterization of Bordetella pertussis strains isolated in São Paulo, Brazil, 1988-2002.

Whooping cough or pertussis was a major cause of childhood morbidity and mortality in the world until the introduction of a whole-cell vaccine in the 1940's. However, since the early 1980's whooping cough cases have increased in many countries, becoming an important problem of public health. This increase may be due to accuracy of laboratory diagnosis and reporting of the disease, a decline in immunity over time, demographic changes, and adaptation of the bacterial population to vaccine-induced immunity. The purpose of this study was to analyze phenotypically and genotypically a collection of 67 Bordetella pertussis isolates recovered during the period 1988-2002 in São Paulo State, Brazil to determine their characteristics and relatedness. All isolates were submitted to susceptibility testing to erythromycin, serotyping, and 56 isolates were analyzed by Pulsed Field Gel Electrophoresis (PFGE). All isolates were susceptible to erythromycin and the majority of them belonged to serotype 1,3. The 56 isolates were classified into 11 PFGE profiles according to the differences in banding patterns. Although more than 60% of the isolates were recovered from patients aged less than three months, almost 15% of them were isolated from adolescents/adults evidencing the increase in the incidence of pertussis among this age group.

Phenotypical and genotypical characterization of Bordetella pertussis strains isolated in São Paulo, Brazil, 1988-2002

Whooping cough or pertussis was a major cause of childhood morbidity and mortality in the world until the introduction of a whole-cell vaccine in the 1940's. However, since the early 1980's whooping cough cases have increased in many countries, becoming an important problem of public health. This increase may be due to accuracy of laboratory diagnosis and reporting of the disease, a decline in immunity over time, demographic changes, and adaptation of the bacterial population to vaccine-induced immunity. The purpose of this study was to analyze phenotypically and genotypically a collection of 67 Bordetella pertussis isolates recovered during the period 1988-2002 in São Paulo State, Brazil to determine their characteristics and relatedness. All isolates were submitted to susceptibility testing to erythromycin, serotyping, and 56 isolates were analyzed by Pulsed Field Gel Electrophoresis (PFGE). All isolates were susceptible to erythromycin and the majority of them belonged to serotype 1,3. The 56 isolates were classified into 11 PFGE profiles according to the differences in banding patterns. Although more than 60 percent of the isolates were recovered from patients aged less than three months, almost 15 percent of them were isolated from adolescents/adults evidencing the increase in the incidence of pertussis among this group of age.

A coqueluche ou pertussis foi a maior causa de morbidade e mortalidade infantil em todo o mundo até a introdução de uma vacina na década de 1940. Entretanto, desde a década de 1980, a coqueluche tornou-se, em muitos países , um importante problema de saúde pública. Este acontecimento pode ser atribuído à melhoria do diagnóstico laboratorial e da notificação da doença, declínio da imunidade no decorrer do tempo, mudanças demográficas ou adaptação da população bacteriana à imunidade induzida pela vacina. O objetivo deste estudo foi analisar as características fenotípicas e genotípicas de uma coleção de 67 cepas de Bordetella pertussis isoladas no período 1988-2002 em São Paulo, Brasil. Todas as cepas foram submetidas à determinação do perfil de resistência à eritromicina, à sorotipagem e 56 cepas à eletroforese em campo pulsado (PFGE). Todas as cepas foram sensíveis à eritromicina e a maioria delas pertencia ao sorotipo 1,3. As 56 cepas foram classificadas em 11 perfis de PFGE com base nas diferenças no padrão de bandas. Embora mais de 60 por cento das cepas tenham sido isoladas de crianças com menos de três meses de idade, cerca de 15 por cento delas era de adolescentes/adultos evidenciando um aumento da incidência da coqueluche nesse grupo etário.

Molecular epidemiology of a nosocomial outbreak due to Enterobacter cloacae and Enterobacter agglomerans in Campinas, São Paulo, Brazil

A total of 73 isolates (57 Enterobacter cloacae and 16 Enterobacter agglomerans), recovered during an outbreak of bacteremia in the Campinas area, São Paulo, Brazil, were studied. Of these isolates, 61 were from parenteral nutrition solutions, 9 from blood cultures, 2 from a sealed bottle of parenteral nutrition solution, and one was of unknown origin. Of the 57 E. cloacae isolates, 54 were biotype 26, two were biotype 66 and one was non-typable. Of 39 E. cloacae isolates submitted to ribotyping, 87.2 percent showed the same banding pattern after cleavage with EcoRI and BamHI. No important differences were observed in the antimicrobial susceptibility patterns among E. cloacae isolates exhibiting the same biotype, serotype and ribotype. All E. agglomerans isolates, irrespective of their origin, showed same patterns when cleaved with EcoRI and BamHI. The results of this investigation suggest an intrinsic contamination of parenteral nutrition solutions and incriminate these products as a vehicle of infection in this outbreak

Surto de bacteriemia por Pseudomonas aeruginosa na unidade de hemodiálise de um hospital de Campinas, Säo Paulo, Brasil / Outbreak of Pseudmonas aeruginosa bacteremia in a Hemodialysis Center in Campinas, Säo Paulo, Brazil

Foram analisadas amostras de água e de dializados coletados de diferentes pontos do sistema de hemodiálise de um Centro de Hemodiálise de um Hospital de Campinas, Säo Paulo, Brasil, após um surto de bacteriemia ocorrido em setembro de 1996. As amostras foram submetidas à contagem de bactérias heterotróficas e pesquisa de coliformes totais, assim como foram realizadas as hemoculturas dos pacientes com bacteriemia. As cepas isoladas e identificadas com Pseudomonas aeruginosa foram submetidas à sorotipagem e à piocinotipagem e, naquelas pertecentes ao mesmo sorotipo e piocinotipo, procurou-se determinar o perfil de sensibilidade aos agentes antimicrobianos e o ribotipo. Quanto à pesquisa de Pseudomonas, 80(por cento) das amostras correspondentes à segunda coleta foram positivas e em todas as amostras referentes à terceira coleta foram isoladas Pseudomonas aeruginosa ou Bulkholderia cepacia. Apenas uma cepa de P.aeruginosa de água pertencia aos mesmos sorotipos (O15) e piocinotipo (P10) daqueles obtidos dos pacientes. A compatibilidade genética das amostras das duas origens, verificada pela ribotipagem, sugere um veículo comum na propagaçäo da infecçäo. (AU)

Between September 11 and 20, 1996, an outbreak of bacteremia occurred in patients undergoing hemodialysis at one dialysis center in Campinas, São Paulo, Brazil. Water and dialysate samples as well asblood samples from patients with bacteremia were collected for bacteriological analysis. All Pseudomonasaeruginosa strains were serotyped and pyocin-typed. P. aeruginosa strains belonging to the same serotype(O15) and pyocin type (P10) were submitted to antimicrobial susceptibility testing and to ribotyping using two restriction enzymes, EcoRI and BamHI. The high concentrations of bacteria detected in all hemodialyzers and their heavy rate of contamination (86.7%) by Pseudomonas aeruginosa or Burkholderia cepacia showed that this dialysis center was operating in inadequate conditions. One strain of P. aeruginosa isolated from hemodialyzer and the strains recovered from blood cultures of patients showed similar phenotypical and genetic traits which suggest a common source of infection in this oubreak. We report the potential risk forpatients undergoing hemodialysis to acquire infections due to the inadequate practice of reusing disposabledialyzers during the reprocessing procedures. (AU)