Standardization and international multicenter validation of a PulseNet pulsed-field gel electrophoresis protocol for subtyping Shigella flexneri isolates

Fil: Pichel, Mariana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Brengi, Silvina P. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Cooper, Kara L. F. Centers for Disease Control and Prevention; Estados Unidos.Fil: Ribot, Efrain M. Centers for Disease Control and Prevention; Georgia.Fil: Al-Busaidy, Suleiman. Central Public Health Laboratory; Omán.Fil: Araya, Pamela. Instituto de Salud Pública de Chile; Chile.Fil: Fernández, Jorge. Instituto de Salud Pública de Chile; Chile.Fil: Vaz, Tania Ibelli. Instituto Adolfo Lutz; Brazil.Fil: Kam, Kai Man. Public Health Laboratory Centre; Japón.Fil: Morcos, Myriam. Regional Center at the U.S. Naval Medical Research Unit #3 (NAMRU-3). Global Disease Detection (GDD); Egipto.Fil: Nielsen, Eva M. Statens Serum Institut; Dinamarca.Fil: Nadon, Celine. National Microbiology Laboratory; Canadá.Fil: Pimentel, Guillermo. Regional Center at the U.S. Naval Medical Research Unit #3 (NAMRU-3). Global Disease Detection (GDD); Egipto.Fil: Pérez-Gutiérrez, Enrique. PAHO/WHO. Health Surveillance; Panamá.Fil: Gerner-Smidt, Peter. Centers for Disease Control and Prevention; Georgia.Fil: Binsztein, Norma. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Shigella flexneri is one of the agents most frequently linked to diarrheal illness in developing countries and often causes outbreaks in settings with poor hygiene or sanitary conditions. Travel is one of the means by which S. flexneri can be imported into developed countries, where this pathogen is not commonly seen. A robust and discriminatory subtyping method is needed for the surveillance of S. flexneri locally and regionally, and to aid in the detection and investigation of outbreaks. The PulseNet International network utilizes standardized pulsedfield gel electrophoresis (PFGE) protocols to carry out laboratory-based surveillance of foodborne pathogens in combination with epidemiologic data. A multicenter validation was carried out in nine PulseNet laboratories located in North and South America, Europe, and Asia, and it demonstrated that a new protocol is highly robust and reproducible for subtyping of S. flexneri. This protocol, already approved for PulseNet laboratories, applies NotI and XbaI as primary and secondary restriction enzymes, respectively, under electrophoresis conditions of initial switch time of 5 s to final switch time of 35 s, at 6 volts/cm

Set of virulence genes and genetic relatedness of O113: H21 Escherichia coli strains isolated from the animal reservoir and human infections in Brazil

Escherichia colt strains of serotype O113. H21 are commonly described as belonging to a Shiga toxin (Stx)-producing E. colt (STEC) pathotype worldwide Albeit this STEC serotype is frequently identified among cattle and other domestic animals, to the best of our knowledge no human infections associated with STEC O113. H21 have been registered in Brazil to date. Here, we report the virulence profile and genetic relatedness of a collection of O113 H21 E coli strains mainly isolated from the animal reservoir aimed at determining their potential as human pathogens. the strains from the animal reservoir (n=34) were all classified as STEC, whereas the few isolates recovered so far from human diarrhoea (n=3) lacked stx genes Among the STEC, the stX(2d-activatable) gene was identified in 85% of the strains that also carried IpfA(O113), iha, saa, ehxA, subAB, astA, cdt-V, espP, espI and epeA, the human strains harboured only lpfA(O113), iha and astA. All the strains except one, isolated from cattle, were genetically classified as phylogenetic group B1 High mass plasmids were observed in 25 isolates, but only in the STEC group were these plasmids confirmed as the STEC O113 megaplasmid (pO113) Many closely related subgroups (more than 80% similarity) were identified by PFGE, with human isolates clustering in a subgroup separate from most of the animal isolates. in conclusion, potentially pathogenic O113 H21 STEC isolates carrying virulence markers in common with O113 H21 clones associated with haemolytic uraemic syndrome cases in other regions were demonstrated to occur in the natural reservoir in our settings, and therefore the risk represented by them to public health should be carefully monitoredFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, São Paulo, BrazilAdolfo Lutz Inst, Bacteriol Sect, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, São Paulo, BrazilFAPESP: 05/04634-8FAPESP: 06/60628-0Web of Scienc

Building PulseNet Latin America and Caribbean Salmonella regional database: First conclusions of genetic subtypes of S. Typhi, S. Typhimurium and S. Enteritidis circulating in six countries of the region

Fil: Campos, Josefina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Pichel, Mariana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Vaz, Tania Ibelli. Instituto Adolfo Lutz; Brasil.Fil: Tavechio, A. T. Instituto Adolfo Lutz; Brasil.Fil: Fernandes, S.A. Instituto Adolfo Lutz; Brasil.Fil: Muñoz, N. Instituto Nacional de Salud; Colombia.Fil: Rodriguez, C. Instituto Nacional de Salud; Colombia.Fil: Realpe, M.E. Instituto Nacional de Salud; Colombia.Fil: Moreno, J. Instituto Nacional de Salud; Colombia.Fil: Araya, Pamela. Instituto de Salud Pública; Chile.Fil: Fernández, J. Instituto de Salud Pública; Chile.Fil: Fernández, A. Instituto de Salud Pública; Chile.Fil: Campos, E. Instituto Costarricense de Investigación y Enseñanza en Nutrición y Salud; Costa Rica.Fil: Duarte, Francisco. Instituto Costarricense de Investigación y Enseñanza en Nutrición y Salud; Costa Rica.Fil: Weiler Gustafson, N. Laboratorio Central de Salud Pública; Paraguay.Fil: Binsztein, Norma. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Pérez Gutierrez, Enrique. Organización Panamericana de la Salud; Brasil.PulseNet Latin America and Caribbean Network (PulseNet LA and C) works together with PulseNet International sharing molecular epidemiologic information for the recognition and investigation of foodborne disease outbreaks. The participants of PulseNet LA and C perform standardized pulsed field gel electrophoresis (PFGE) protocols and analysis generating data that is incorporated into Regional Databases. In this study we present the relationship and distribution of genetic subtypes of Salmonella enterica ser. Typhimurium (STM), Salmonella enterica ser. Enteritidis (SE), and Salmonella enterica ser. Typhi (ST) human isolates circulating in six countries of the Region between 2005 and 2009, from the analysis of the Salmonella Database. The 70 ST isolates analyzed were diverse and none of the countries shared the same PFGE profiles with XbaI enzyme. These results show a high genetic diversity among the strains studied and provide background to trace future outbreaks and travel related cases. In the analysis of 550 STM isolates, we found 10 patterns shared at least between two countries, suggesting the need of further studies of attribution to the source of origin. Only one of these PFGE patterns was associated with a known outbreak. Among 225 SE isolates, a predominant subtype was identified, that grouped 83.5% of the isolates and was associated with foodborne outbreaks in five of the six countries; showing the need to use other subtyping techniques for this serovar. The continuous update of PulseNet LA and C Salmonella Regional Database provides an important tool for the laboratory based surveillance of the serovars analyzed, for the prevention and control of foodborne outbreaks, and for the detection of emerging strains in the Region

Agentes bacterianos isolados de líquido cefalorraquidiano de pacientes com Síndrome de Imunodeficiência Adquirida (SIDA) e complicações neurológicas

Cerebrospinal fluid (CSF) samples from 2083 patients with acquired immunodeficiency syndrome (AIDS) and neurological complications were bacteriologically examined during a period of 7 years (1984-1990). The percentage of patients who had at least one bacterial agent cultured from the CSF was 6.2%. Mycobacterium tuberculosis was the most frequently isolated agent (4.3%), followed by Mycobacterium avium complex or MAC (0.7%), Pseudomonas spp (0.5%), Enterobacter spp (0.4%), and Staphylococcus aureus (0.3%). Among 130 culture positive patients, 89 (68.5%) had M. tuberculosis and 15 (11.6%) had MAC. The frequency of bacterial isolations increased from 1988 (5.2%) to 1990 (7.2%), partly due to the increase in MAC isolations. Bacterial agents were more frequently isolated from patients in the age group 21-30 years and from women (pAmostras de líquido cefalorraquidiano (LCR) de 2083 pacientes com Síndrome de Imunodeficiência Adquirida (SIDA) e complicações neurológicas foram examinados durante um período de 7 anos (1984-1990). A porcentagem de pacientes que tiveram pelo menos um agente bacteriano cultivado do LCR foi de 6,2%. Mycobacterium tuberculosis foi o mais frequentemente isolado (4,3%), seguido do complexo Mycobacterium avium ou MAC (0,7%), de Pseudomonas spp (0,5%), Enterobacter spp (0,4%), e Staphylococcus aureus (0,3%). Entre 130 pacientes com cultura positiva, de 89 (68,5%) foi isolado M. tuberculosis e de 15 (11,6%) MAC. A frequência de isolamentos bacterianos aumentou de 1988 (5,2%) a 1990 (7,2%), particularmente devido ao maior isolamento de MAC. Os agentes bacterianos foram mais frequentemente isolados de pacientes na faixa etária de 21-30 anos e de mulheres (

Bacterial agents isolated from cerebrospinal fluid of patients with Acquired Immunodeficiency Syndrome (AIDS) and neurological complications

Cerebrospinal fluid (CSF) samples from 2083 patients with acquired immunodeficiency syndrome (AIDS) and neurological complications were bacteriologically examined during a period of 7 years (1984-1990). The percentage of patients who had at least one bacterial agent cultured from the CSF was 6.2%. Mycobacterium tuberculosis was the most frequently isolated agent (4.3%), followed by Mycobacterium avium complex or MAC (0.7%), Pseudomonas spp (0.5%), Enterobacter spp (0.4%), and Staphylococcus aureus (0.3%). Among 130 culture positive patients, 89 (68.5%) had M. tuberculosis and 15 (11.6%) had MAC. The frequency of bacterial isolations increased from 1988 (5.2%) to 1990 (7.2%), partly due to the increase in MAC isolations. Bacterial agents were more frequently isolated from patients in the age group 21-30 years and from women (p<0.05)