Presence of genes encoding enterotoxins in Staphylococcus aureus isolates recovered from food, food establishment surfaces and cases of foodborne diseases

The aim of this study was to describe the microbiological characteristics and profile of genes encoding enterotoxins in 95 Staphylococcus aureus isolates obtained between April 2011 and December 2014 from foodstuffs, persons and surfaces of retail food stores. After microbiological identification and antimicrobial susceptibility testing, polymerase chain reactions (PCR) were performed, targeting sea, seb, sec, sed and see genes that code for classical enterotoxins (ET) A-E, and three additional genes: seg, seh and sei, coding for so-called “new enterotoxins” G, H and I. The isolates were characterized by Pulsed Field Gel Electrophoresis (PFGE), and five selected isolates were further analyzed through Multi Locus Sequence Typing (MLST). It is noteworthy that 54.7% of the examined isolates harbored one or more of the investigated ET gene types. Most positive isolates carried more than one ET gene up to five types; seg was the most frequent ET gene, followed by sei. Five enterotoxin-coding isolates also coded for some antimicrobial resistance genes. Two of them, and four additional non-enterotoxic isolates carried erm genes expressing inducible clindamycin resistance. PFGE-types were numerous and diverse, even among enterotoxin-coding strains, because most isolates did not belong to known foodborne outbreaks and the sampling period was long. MLST profiles were also varied, and a new ST 3840 was described within this species. ST 88 and ST 72 enterotoxin-coding isolates have been identified in other regions in association with foodborne outbreaks. This manuscript reports the first systematic investigation of enterotoxin genes in S. aureus isolates obtained from foodstuffs and infected people in Urugua

Resistance to non-beta-lactamantibiotics in the clinicalisolates of Streptococcuspneumoniaeof children inLatin America. SIREVA II,2000–2005

Fil: Agudelo, Clara Inés. Instituto Nacional de Salud; Colombia.Fil: Castañeda, Elizabeth. Instituto Nacional de Salud; Colombia.Fil: Corso, Alejandra. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Regueira, Mabel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: de Cunto Brandileone, María Cristina. Instituto Adolfo Lutz; Brasil.Fil: Pires Brandão, Angela. Fundação Oswaldo Cruz; Brasil.Fil: Maldonado, Aurora. Instituto de Salud Pública; Chile.Fil: Hormazabal, Juan Carlos. Instituto de Salud Pública; Chile.Fil: Tamargo, Isis. Instituto de Medicina Tropical Pedro Kourí; Cuba.Fil: Echániz-Avilés, Gabriela. Instituto Nacional de Salud Pública; México.Fil: Soto, Araceli. Instituto Nacional de Salud Pública; México.Fil: Viveros, Mónica Guadalupe. Instituto de Diagnóstico y Referencia Epidemiológicos; México.Fil: Hernández, Irma. Instituto de Diagnóstico y Referencia Epidemiológicos; México.Fil: Chamorro, Gustavo. Laboratorio Central de Salud Pública; Paraguay.Fil: Weiler, Natalie. Laboratorio Central de Salud Pública; Paraguay.Fil: Sánchez, Jacqueline. Hospital Infantil Dr. Robert Reid Cabral; República Dominicana.Fil: Feris, Jesús M. Hospital Infantil Dr. Robert Reid Cabral; República Dominicana.Fil: Camou, Teresa. Servicio Nacional de Laboratorios de Salud Pública; Uruguay.Fil: García, Gabriela. Servicio Nacional de Laboratorios de Salud Pública; Uruguay.Fil: Spadola, Enza. Instituto Nacional de Higiene Rafael Rangel; Venezuela.Fil: Payares, Daisy. Instituto Nacional de Higiene Rafael Rangel; Venezuela.Fil: Gabastou, Jean-Marc. Organización Panamericana de la Salud; Estados Unidos.Fil: di Fabio, José Luis. Organización Panamericana de la Salud; Estados Unidos.Fil: Grupo SIREVA II; Argentina.Objetivo. Determinar la evolución de la resistencia a la eritromicina, el cloranfenicol, el trimetoprim-sulfametozaxol (SXT) y la vancomicina de aislamientos invasores de Streptococcus pneumoniaeobtenidos de niños de 10 países de América Latina y del Caribe en seis años de vigilancia. Métodos. Se analizaron 8 993 aislamientos de S. pneumoniaerecuperados entre 2000 y 2005 de niños menores de 6 años con infecciones invasoras, procedentes de Argentina, Brasil, Chile, Colombia, Cuba, México, Paraguay, República Dominicana, Uruguay y Venezuela. La sensibilidad a los antibióticos se determinó mediante los métodos establecidos y estandarizados en el proyecto SIREVA. La resistencia a múltiples antibióticos se definió como la resistencia a tres o más familias de antibióticos, de los no betalactámicos analizados en este estudio o de los betalactámicos evaluados en un estudio previo en el que 37,8% de estos aislamientos presentaron sensibilidad disminuida a la penicilina. Resultados. Se encontró algún grado de resistencia al SXT y la eritromicina (56,4% y 15,4% de los aislamientos estudiados, respectivamente) y 4,6% presentó alta resistencia al cloranfenicol. Todos los aislamientos fueron sensibles a la vancomicina. Se observó la mayor frecuencia de resistencia al SXT en los aislamientos de neumonía y a la eritromicina en los casos de sepsis (61,6% y 25,5%, respectivamente; P< 0,01). La mayor frecuencia de resistencia al SXT se observó en Brasil (71,9%) y a la eritromicina en México (38,2%) y Venezuela (32,9%). Los serotipos 14, 6B, 19F y 23F fueron los que más frecuentemente se asociaron con la resistencia a los antibióticos estudiados. Conclusiones. Se observó una elevada y creciente frecuencia de aislamientos resistentes al SXT y la eritromicina, y una disminución en la proporción de aislamientos resistentes al cloranfenicol. Estas tendencias mostraron diferencias entre los países estudiado

Resistance to non-beta-lactamantibiotics in the clinicalisolates of Streptococcuspneumoniaeof children inLatin America. SIREVA II,2000–2005

Fil: Agudelo, Clara Inés. Instituto Nacional de Salud; Colombia.Fil: Castañeda, Elizabeth. Instituto Nacional de Salud; Colombia.Fil: Corso, Alejandra. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Regueira, Mabel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: de Cunto Brandileone, María Cristina. Instituto Adolfo Lutz; Brasil.Fil: Pires Brandão, Angela. Fundação Oswaldo Cruz; Brasil.Fil: Maldonado, Aurora. Instituto de Salud Pública; Chile.Fil: Hormazabal, Juan Carlos. Instituto de Salud Pública; Chile.Fil: Tamargo, Isis. Instituto de Medicina Tropical Pedro Kourí; Cuba.Fil: Echániz-Avilés, Gabriela. Instituto Nacional de Salud Pública; México.Fil: Soto, Araceli. Instituto Nacional de Salud Pública; México.Fil: Viveros, Mónica Guadalupe. Instituto de Diagnóstico y Referencia Epidemiológicos; México.Fil: Hernández, Irma. Instituto de Diagnóstico y Referencia Epidemiológicos; México.Fil: Chamorro, Gustavo. Laboratorio Central de Salud Pública; Paraguay.Fil: Weiler, Natalie. Laboratorio Central de Salud Pública; Paraguay.Fil: Sánchez, Jacqueline. Hospital Infantil Dr. Robert Reid Cabral; República Dominicana.Fil: Feris, Jesús M. Hospital Infantil Dr. Robert Reid Cabral; República Dominicana.Fil: Camou, Teresa. Servicio Nacional de Laboratorios de Salud Pública; Uruguay.Fil: García, Gabriela. Servicio Nacional de Laboratorios de Salud Pública; Uruguay.Fil: Spadola, Enza. Instituto Nacional de Higiene Rafael Rangel; Venezuela.Fil: Payares, Daisy. Instituto Nacional de Higiene Rafael Rangel; Venezuela.Fil: Gabastou, Jean-Marc. Organización Panamericana de la Salud; Estados Unidos.Fil: di Fabio, José Luis. Organización Panamericana de la Salud; Estados Unidos.Fil: Grupo SIREVA II; Argentina.Objetivo. Determinar la evolución de la resistencia a la eritromicina, el cloranfenicol, el trimetoprim-sulfametozaxol (SXT) y la vancomicina de aislamientos invasores de Streptococcus pneumoniaeobtenidos de niños de 10 países de América Latina y del Caribe en seis años de vigilancia. Métodos. Se analizaron 8 993 aislamientos de S. pneumoniaerecuperados entre 2000 y 2005 de niños menores de 6 años con infecciones invasoras, procedentes de Argentina, Brasil, Chile, Colombia, Cuba, México, Paraguay, República Dominicana, Uruguay y Venezuela. La sensibilidad a los antibióticos se determinó mediante los métodos establecidos y estandarizados en el proyecto SIREVA. La resistencia a múltiples antibióticos se definió como la resistencia a tres o más familias de antibióticos, de los no betalactámicos analizados en este estudio o de los betalactámicos evaluados en un estudio previo en el que 37,8% de estos aislamientos presentaron sensibilidad disminuida a la penicilina. Resultados. Se encontró algún grado de resistencia al SXT y la eritromicina (56,4% y 15,4% de los aislamientos estudiados, respectivamente) y 4,6% presentó alta resistencia al cloranfenicol. Todos los aislamientos fueron sensibles a la vancomicina. Se observó la mayor frecuencia de resistencia al SXT en los aislamientos de neumonía y a la eritromicina en los casos de sepsis (61,6% y 25,5%, respectivamente; P< 0,01). La mayor frecuencia de resistencia al SXT se observó en Brasil (71,9%) y a la eritromicina en México (38,2%) y Venezuela (32,9%). Los serotipos 14, 6B, 19F y 23F fueron los que más frecuentemente se asociaron con la resistencia a los antibióticos estudiados. Conclusiones. Se observó una elevada y creciente frecuencia de aislamientos resistentes al SXT y la eritromicina, y una disminución en la proporción de aislamientos resistentes al cloranfenicol. Estas tendencias mostraron diferencias entre los países estudiado

Dissemination of Streptococcus pneumoniae Clone Colombia(5)-19 in Latin America

Streptococcus pneumoniae serotype 5 is the third most common capsular type causing invasive diseases in children younger than 5 years in Latin America. Preliminary data on Colombian serotype 5 isolates indicated a common clonal origin associated with resistance to tetracycline (TET) and chloramphenicol (CHL). We studied 172 S. pneumoniae serotype 5 invasive isolates from Argentina, Brazil, Colombia, Guatemala, Mexico, and Uruguay and confirmed the presence of the Colombia(5)-19 clone throughout Latin America. Fifteen subtypes of a pulsed-field gel electrophoresis pattern and 4 electrophoretic types (ET) were obtained. Most of the isolates from different geographical regions belonged to pattern A (34.3%), subtype A5 (41.9%), and ET1 (91.1%). The A pattern (n = 59) was resistant to TET and had variable resistance to CHL; it was present in Brazil (10.2%), Colombia (78%), Guatemala (8.5%), and Mexico (3.4%). Subtype A5 with variable susceptibility to TET and sensitive to CHL was found in Argentina (29.2%), Mexico (8.3%), and Uruguay (62.5%). Subtypes A1-A4, A7-A8, and A9-A11 (closely related to A) also shared ET1, while subtype A6 was assigned to ET1, ET2, and ET3. Eleven subtypes (n = 21) were found to be specific for one country each. In summary, the S. pneumoniae serotype 5 isolates from Latin American are genetically closely related but show different patterns of antibiotic resistance, probably as a result of horizontal transfer

Detección de cepas de Neisseria meningitidis resistentes a rifampicina en el Uruguay Detection of rifampicin-resistant strains of Neisseria meningitidis in Uruguay

El objetivo de este trabajo fue caracterizar fenotípica y genotípicamente dos aislamientos de Neisseria meningitidis resistentes a rifampicina relacionados con dos eventos independientes de transmisión de enfermedad meningocócica grave que se presentaron en septiembre y octubre de 2010 en Montevideo, Uruguay. Se revisó también la base de datos de la vigilancia nacional de resistencia a los antimicrobianos de los últimos 10 años, para estimar la frecuencia de la particularidad de los meningococos caracterizados. La resistencia a rifampicina se estudió por el método epsilométrico. El serotipo y serosubtipo de los aislamientos se determinaron por ELISA y la caracterización genotípica se realizó por digestión del ADN con NheI y electroforesis en gel con campo pulsátil. Ambos aislamientos eran idénticos, B:2a:P1.5, y su fenotipo no figuraba en la colección de 408 cepas de N. meningitidis aisladas en el Uruguay en los últimos 10 años, con la excepción de dos aislamientos sensibles a rifampicina. Los dos aislamientos estudiados también compartían un pulsotipo único, diferente del de otros dos aislamientos resistentes a rifampicina obtenidos en 2003 y 2007. Por lo tanto, ambos eventos de transmisión fueron causados por una única cepa resistente a rifampicina, que podría haberse introducido al país desde otras regiones o haberse originado por un cambio del serogrupo C al B, como producto de la presión selectiva ejercida por vacunas administradas a la población. Es necesario mantener y extremar la vigilancia. No obstante, en vista de que hasta el momento este tipo de hallazgo ha sido esporádico, no se justifica cambiar el fármaco antimicrobiano que se administra a los contactos para la profilaxis, a menos que se identifique un caso secundario.The objective of this study was to characterize the phenotype and genotype of two isolates of rifampicin-resistant Neisseria meningitidis associated with two independent events involving transmission of severe meningococcal meningitis that occurred in September and October 2010 in Montevideo, Uruguay. The most recent 10 years of data from the national antimicrobial resistance surveillance system were reviewed to estimate the frequency of the particular meningococcal features that were characterized. Rifampicin resistance was studied using the epsilometer test. The serotype and serosubtype of the isolates were determined by ELISA, and the genotype was characterized using DNA digestion with Nhel and pulse field gel electrophoresis. The two isolates were identical: B:2a:P1.5. In the collection of 408 strains of N. meningitidis isolated in Uruguay in the past 10 years, the phenotype only appeared in two isolates, which were sensitive to rifampicin. The two isolates studied also shared a single pulse type, which was different from that of two other rifampicin-resistant isolates obtained in 2003 and 2007. Consequently, it was concluded that both cases of transmission were caused by a single rifampicin-resistant strain, which could have been an import from another country or else the result of a drift from serogroup C to B due to selective pressure exerted by vaccines administered to the population. It is essential to maintain and maximize surveillance. However, since this type of finding has been sporadic so far, unless a secondary case is identified, there is no justification for changing the antimicrobial drug currently being administered to contacts as prophylaxis

Characterization of Streptococcus equi subsp. zooepidemicus isolates containing lnuB gene responsible for the L phenotype.

Within the framework of the β-hemolytic streptococci surveillance carried out by the National Reference Laboratory from Uruguay, three putative Streptococcus equi subsp. zooepidemicus (SEZ) were received from different health centers. Being these the first reports associated with human infections in Uruguay, the objective of this work was to confirm their identification, to determine their genetic relationship and to study their antibiotic susceptibility. Using four different methods, they were identified as SEZ, a subspecies which has been described as the etiologic agent of rare and severe zoonosis in a few cases in other countries. The three isolates presented different pulsotypes by PFGE; however, two of them appeared to be related and were confirmed as ST431 by MLST, while the remaining isolate displayed ST72. Their resistance profile exhibited an unexpected feature: despite all of them were susceptible to macrolides, they showed different levels of resistance to clindamycin, i.e. they had the so-called "L phenotype". This rare trait is known to be due to a nucleotidyl-transferase, encoded by genes of the lnu family. Although this phenotype was previously described in a few SEZ isolates, its genetic basis has not been studied yet. This was now analyzed by PCR in the three isolates and they were found to contain a lnuB gene. The lnuB sequence was identical among the three isolates and with many lnuB sequences deposited in data banks. In conclusion, for the first time in Uruguay, three SEZ isolates recovered from non-epidemiologically related cases of human invasive infection were identified. Moreover, this is the first report about the presence of a lnu gene in the S. equi species, revealing the active lateral spread of the lnuB in a new streptococcal host

Caracterización molecular de aislamientos de Streptococus pneumoniae, serotipo 5 causante de enfermedad invasiva en niños latinoamericanos

IP 2104-04-302-98Incluye anexos.pneumoniae invasive insolates / Gamboa L. ... [et al.]. --En:International Congress for Tropical Medicine;and Malaria (15 : 2000 Ago. 20-25 : Cartagena, Colombia).-- Cartagena, 2000. -- p. -- 28 cm. -- ARTICULO(S);EN REVISTA: Dissemination of streptococcus pneumoniae clone Colombia 5-19in Latin America / Elizabeth;Castañeda ... [et al]. -- En: Journal of Clinical Microbiology.-- Vol. 40, no. 11. (Nov. 2002); p.;3942-3950.;PONENCIA(S) EN CONGRESO: Molecular characterization of Latin American children`s serotype 5 streptococcu

Effect of pneumococcal conjugate vaccination in Uruguay, a middle-income country.

In 2008, a 7-valent pneumococcal conjugate vaccine (PCV7) was introduced into the routine childhood immunization program in Uruguay, with a 2+1 schedule. In 2010, PCV13 replaced PCV7, and the same 2+1 schedule was used. The effect of these pneumococcal vaccines on the incidence of invasive pneumococcal infections (IPD) and on serotype distribution was analyzed retrospectively, based on passive national laboratory surveillance.Data from 1,887 IPD isolates from 5 years before and 5 years after PCV7 introduction (7 before and 3 after PCV13 introduction) was examined to assess the incidence rate per 100,000 age-specific population of all IPD, PCV7-serotypes, and PCV13-serotypes associated IPD among children < 2 years and 2 to 4 years old, and patients ≥ 5 years old. Trends of frequency for each serotype were also analyzed.Comparison of pre-vaccination (2003-2007) and post-vaccination (2008-2012) periods showed a significant decrease in IPD incidence among children < 2 years old (IR 68.7 to IR 29.6, p<0.001) and children 2 to 4 years (p < 0.04). IPD caused by serotypes in PCV7 was reduced by 95.6% and IPD caused by 6 serotypes added in PCV13 was reduced by 83.9% in children <5 years old. Indirect effects of both conjugate vaccines were observed among patients ≥ 5 years old one year after the introduction of each vaccine, in 2010 for PCV7 and in 2012 for PCV13. Nevertheless, for reasons that still need to be explained, perhaps due to ascertainment bias, total IPD in this group increased after 2007. In 2012, the relative frequency of vaccine serotypes among vaccinated and unvaccinated population declined, except for serotype 3. Non vaccine serotypes with increasing frequency were identified, in rank order: 12F, 8, 24F, 22F, 24A, 15C, 9N, 10A and 33.Consecutive immunization with PCV7 and PCV13 has significantly reduced IPD in children < 5 years of age in Uruguay

Serotypes and clonal types of penicillin-susceptible streptococcus pneumoniae causing invasive disease in children in five Latin American countries

Fil: Zemlicková, Helena. The Rockefeller University, New York; Estados Unidos.Fil: Crisóstomo, M Inês. Laboratory of Microbiology, The Rockefeller University, New York; Argentina.Fil: Brandileone, Maria Cristina. Instituto Adolfo Lutz, São Paulo, Brasil.Fil: Camou, Teresa. Area of Technology and Health Services Delivery, Unit of Essential Medicines, Vaccines and Health Technology; Estados Unidos.Fil: Castañeda, Elizabeth. Instituto Nacional de Salud, Bogotá; Colombia.Fil: Corso, Alejandra. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Bacteriología; Argentina.Fil: Echániz-Aviles, Gabriela. Instituto Nacional de Salud Pública, Cuernavaca; Mexico.Fil: Pásztor, Mónika. Department of Biochemistry, Szent-Györgyi A. Medical University, Szeged; Hungría.Fil: Tomasz, Alexander. Laboratory of Microbiology, The Rockefeller University, New York; Argentina.We used multilocus sequencing typing (MLST) to determine the genetic backgrounds of 185 recent penicillin susceptible Streptococcus pneumoniae isolates with serotypes that most frequently cause invasive disease in preschool age children in five Latin American countries-Argentina, Brazil, Colombia, Mexico, and Uruguay. Most of the isolates were associated with pneumonia (90/185), meningitis (74/185), and bacteremia (17/185). The collection of strains included seven serotypes-14, 6B, 5, 1, 23 F-which represent the serotypes of S. pneumoniae most frequently associated with sterile site infections in children. Also included were strains expressing serotypes 7F and 3. Comparison of serotype and multilocus sequence type allowed division of the isolates into two groups: strains expressing serotypes 1, 5, 3, and 7 were represented by a relatively few sequence types while strains expressing serotypes 6B, 14, and 23 F showed great genetic diversity. The genetic diversity of serotypes 14, 6B, and 23 F may be related to the capacity of these serotypes to colonize the nasopharynx of healthy carriers during which opportunities for diversification through genetic exchanges can occur. The findings present an interesting contrast with the results of an earlier study in which over 80% of invasive penicillin- resistant serotype 14 and 23 isolates from the same countries were found to belong to as few as two pandemic clones of S. pneumoniae

Protection against Streptococcus pneumoniae serotype 1 acute infection shows a signature of Th17- and IFN-γ-mediated immunity.

International audienceAcute pneumonia caused by Streptococcus pneumoniae is a major cause of child mortality. Antibodies are considered the main effectors of protection in this clinical presentation of pneumococcal invasive disease. To get new insights into the mechanisms involved in the protective immunity, we established a murine experimental model of protection against acute pneumococcal pneumonia and then evaluated the transcriptional, humoral and cellular responses in protected and non-protected animals. We found that intranasal inoculation of a sublethal dose of S. pneumoniae serotype 1 conferred complete protection against a subsequent challenge with a lethal dose of the same strain. Sublethal infection elicited a strong IgM and IgG antibody response against the capsular polysaccharide, as assessed one week later, and an exacerbated influx of neutrophils into the lungs immediately after the lethal challenge. Genome-wide microarray-based transcriptional analysis of whole lungs showed 149 differentially expressed genes among which we found upregulation of Il17a, Ifng and several IL-17A- and IFN-γ-related genes in protected versus non-protected mice. Kinetics analysis showed higher expression levels of Il17a in protected animals at all time points whereas Ifng was upregulated early in the protected mice and later in the non-protected animals. Intracelluar cytokine staining demonstrated that CD4(+) T cells account for a great proportion of the IL-17A produced in the lungs of protected animals. Overall, these results showed that an upregulation of IL-17A- and a timely regulation of IFN-γ-related gene expression, together with development of a Th17 response, are relevant characteristics of the protective immunity against S. pneumoniae acute pneumonia