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Dekaj E, Gjini E. Pneumococcus and the stress-gradient hypothesis: A trade-off links R 0 and susceptibility to co-colonization across countries. Theor Popul Biol 2024; 156:77-92. [PMID: 38331222 DOI: 10.1016/j.tpb.2024.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 10/06/2023] [Accepted: 02/01/2024] [Indexed: 02/10/2024]
Abstract
Modern molecular technologies have revolutionized our understanding of bacterial epidemiology, but reported data across studies and different geographic endemic settings remain under-integrated in common theoretical frameworks. Pneumococcus serotype co-colonization, caused by the polymorphic bacteria Streptococcus pneumoniae, has been increasingly investigated and reported in recent years. While the global genomic diversity and serotype distribution of S. pneumoniae have been well-characterized, there is limited information on how co-colonization patterns vary globally, critical for understanding the evolution and transmission dynamics of the bacteria. Gathering a rich dataset of cross-sectional pneumococcal colonization studies in the literature, we quantified patterns of transmission intensity and co-colonization prevalence variation in children populations across 17 geographic locations. Linking these data to an SIS model with cocolonization under the assumption of quasi-neutrality among multiple interacting strains, our analysis reveals strong patterns of negative co-variation between transmission intensity (R0) and susceptibility to co-colonization (k). In line with expectations from the stress-gradient-hypothesis in ecology (SGH), pneumococcus serotypes appear to compete more in co-colonization in high-transmission settings and compete less in low-transmission settings, a trade-off which ultimately leads to a conserved ratio of single to co-colonization μ=1/(R0-1)k. From the mathematical model's behavior, such conservation suggests preservation of 'stability-diversity-complexity' regimes in coexistence of similar co-colonizing strains. We find no major differences in serotype compositions across studies, pointing to adaptation of the same set of serotypes across variable environments as an explanation for their differential interaction in different transmission settings. Our work highlights that the understanding of transmission patterns of Streptococcus pneumoniae from global scale epidemiological data can benefit from simple analytical approaches that account for quasi-neutrality among strains, co-colonization, as well as variable environmental adaptation.
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Affiliation(s)
- Ermanda Dekaj
- Center for Computational and Stochastic Mathematics, Instituto Superior Técnico, University of Lisbon, Lisbon, Portugal
| | - Erida Gjini
- Center for Computational and Stochastic Mathematics, Instituto Superior Técnico, University of Lisbon, Lisbon, Portugal.
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de Felipe B, Aboza-García M, González-Galán V, Salamanca de la Cueva I, Martín-Quintero JA, Amil-Pérez B, Coronel-Rodríguez C, Palacios-Soria MÁ, García Ruiz-Santaquiteria MI, Torres-Sánchez MJ, Morón FJ, Cordero-Varela JA, Obando-Pacheco P, Obando I. Molecular epidemiology of pneumococcal carriage in children from Seville, following implementation of the PCV13 immunization program in Andalusia, Spain. ENFERMEDADES INFECCIOSAS Y MICROBIOLOGIA CLINICA (ENGLISH ED.) 2024; 42:172-178. [PMID: 37085445 DOI: 10.1016/j.eimce.2023.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/18/2022] [Accepted: 11/20/2022] [Indexed: 04/23/2023]
Abstract
INTRODUCTION The 13-valent pneumococcal conjugate vaccine (PCV13) universal vaccination programme was introduced in December 2016 in Andalusia. METHODS A cross-sectional study was conducted on the molecular epidemiology of pneumococcal nasopharyngeal colonization. A total of 397 healthy children were recruited from primary healthcare centres in Seville for the periods 1/4/2018 to 28/2/2020 and 1/11/2021 to 28/2/2022 (PCV13 period). Data from a previous carriage study conducted among healthy and sick children from 1/01/2006 to 30/06/2008 (PCV7 period), were used for comparison of serotype/genotype distributions and antibiotic resistance rates. RESULTS Overall, 76 (19%) children were colonized with S. pneumoniae during the PCV13 period and there were information available from 154 isolates collected during the PCV7 period. Colonization with PCV13 serotypes declined significantly in the PCV13 period compared with historical controls (11% vs 38%, p = 0.0001), being serotypes 19F (8%), 3 (1%) and 6B (1%) the only circulating vaccine types. Serotypes 15B/C and 11A were the most frequently identified non-PCV13 serotypes during the PCV13 period (14% and 11%, respectively); the later one increased significantly between time periods (p = 0.04). Serotype 11A was exclusively associated in the PCV13 period with ampicillin-resistant variants of the Spain9V-ST156 clone (ST6521 and genetically related ST14698), not detected in the preceding period. CONCLUSIONS There was a residual circulation of vaccine types following PCV13 introduction, apart from serotype 19F. Serotype 11A increased between PCV13 and PCV7 periods due to emergence and clonal expansion of ampicillin-resistant genotype ST6521.
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Affiliation(s)
- Beatriz de Felipe
- Alteraciones Congénitas de la Inmunidad, Instituto de Biomedicina de Sevilla (IBIS), Universidad de Sevilla/Hospital Universitario Virgen del Rocío (HUVR)/CSIC, Sevilla, Spain
| | - Marta Aboza-García
- Alteraciones Congénitas de la Inmunidad, Instituto de Biomedicina de Sevilla (IBIS), Universidad de Sevilla/Hospital Universitario Virgen del Rocío (HUVR)/CSIC, Sevilla, Spain; Centro de Salud Polígono Norte, Sevilla, Spain
| | | | | | | | - Benito Amil-Pérez
- Servicio de Pediatría, Grupo Instituto Hispalense de Pediatría, Sevilla, Spain
| | - Cristóbal Coronel-Rodríguez
- Centro de Salud Amante Laffón, Distrito de Atención Primaria Sevilla, Servicio Andaluz de Salud, Sevilla, Spain
| | | | | | | | - Francisco Javier Morón
- Unidad de Genómica, Instituto de Biomedicina de Sevilla, Universidad de Sevilla/Hospital Universitario Virgen del Rocío/CSIC, Sevilla, Spain
| | - Juan A Cordero-Varela
- Unidad de Bioinformática, Instituto de Biomedicina de Sevilla, Universidad de Sevilla/Hospital Universitario Virgen del Rocío/CSIC, Sevilla, Spain
| | | | - Ignacio Obando
- Alteraciones Congénitas de la Inmunidad, Instituto de Biomedicina de Sevilla (IBIS), Universidad de Sevilla/Hospital Universitario Virgen del Rocío (HUVR)/CSIC, Sevilla, Spain; Sección de Infectología e Inmunopatologías Pediátricas, Hospital Universitario Virgen de Valme, Sevilla, Spain
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de Felipe B, Aboza-García M, González-Galán V, Salamanca de la Cueva I, Martín-Quintero JA, Amil-Pérez B, Coronel-Rodríguez C, Palacios-Soria MÁ, García Ruiz-Santaquiteria MI, Torres-Sánchez MJ, Morón FJ, Cordero-Varela JA, Obando-Pacheco P, Obando I. Epidemiología molecular de la colonización nasofaríngea neumocócica en niños de Sevilla, tras la implementación del programa de vacunación con VNC13 en Andalucía (España). Enferm Infecc Microbiol Clin 2023. [DOI: 10.1016/j.eimc.2022.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Gámez G, Rojas JP, Cardona S, Castillo Noreña JD, Palacio MA, Mejía LF, Torres JL, Contreras J, Muñoz LM, Criales J, Vélez LF, Forero AM, Zúñiga YA, Cuastumal ME, Acevedo LJ, Molina ÁDJ, Bolivar JA, Gómez-Mejia A, Morales JL, Hammerschmidt S. Factors Associated with Streptococcus pneumoniae Nasopharyngeal Carriage and Antimicrobial Susceptibility among Children Under the Age of 5 Years in the Southwestern Colombia. J PEDIAT INF DIS-GER 2021. [DOI: 10.1055/s-0041-1731343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Abstract
Objective This work aimed to evaluate the factors associated with Streptococcus pneumoniae nasopharyngeal colonization and antimicrobial susceptibility among pediatric outpatients in southwestern Colombia, 2019.
Methods A cross-sectional study was performed using survey-based interviews and the collection of nasopharyngeal-swab specimens for microbiological characterization and antimicrobial susceptibility testing. Logistic regression analyses were performed for factors associated with nasopharyngeal carriage.
Results A total of 452 children under the age of 5 years were examined in which 41.8% carried S. pneumoniae. Higher pneumococcal carriage frequencies were observed among participants aged <2 years and in individuals belonging to indigenous communities, which were lacking established pneumococcal-conjugated vaccine-10 immunization schemes. Additionally, children attending childcare institutions were also highly colonized by pneumococci. S. pneumoniae showed 57.7% nonsusceptibility to benzyl-penicillin (meningitis-cut); 45.5% intermediate-sensitivity to benzyl-penicillin (oral-cut) and 21.7% to cefotaxime; and resistance to erythromycin (40.7%), tetracycline (36.0%), trimethoprim/sulfamethoxazole (24.9%), clindamycin (24.3%), and ceftriaxone (27.0%).
Conclusion The 41.8% of participants carrying S. pneumoniae show a scenario with the presence of multidrug and extensively drug-resistant strains, which constitutes important reservoirs of bacterial transmission by children aged <5 years in Colombia, leading to an onset of pneumococcal diseases. Hence, there is an urgent need to expand conjugate pneumococcal immunization in the community and ensure compliance with established immunization schedules.
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Affiliation(s)
- Gustavo Gámez
- Basic and Applied Microbiology Research Group, School of Microbiology, University of Antioquia, UdeA, Medellín, Colombia
- Genetics, Regeneration and Cancer Research Group, University Research Center, University of Antioquia, UdeA, Medellín, Colombia
| | - Juan Pablo Rojas
- Club Noel Children's Clinical Foundation, Cali, Colombia
- Pediatrics Graduate Program, School of Medicine, University Libre Sectional Cali, Cali, Colombia
- School of Health, Valle University, Cali, Colombia
| | - Santiago Cardona
- Genetics, Regeneration and Cancer Research Group, University Research Center, University of Antioquia, UdeA, Medellín, Colombia
| | | | - María Alejandra Palacio
- Basic and Applied Microbiology Research Group, School of Microbiology, University of Antioquia, UdeA, Medellín, Colombia
| | - Luis Fernando Mejía
- Club Noel Children's Clinical Foundation, Cali, Colombia
- Pediatrics Graduate Program, School of Medicine, University Libre Sectional Cali, Cali, Colombia
| | - José Luis Torres
- Basic and Applied Microbiology Research Group, School of Microbiology, University of Antioquia, UdeA, Medellín, Colombia
| | | | - Laura Mery Muñoz
- Basic and Applied Microbiology Research Group, School of Microbiology, University of Antioquia, UdeA, Medellín, Colombia
| | - Javier Criales
- Club Noel Children's Clinical Foundation, Cali, Colombia
- Pediatrics Graduate Program, School of Medicine, University Libre Sectional Cali, Cali, Colombia
| | - Luis Felipe Vélez
- Genetics, Regeneration and Cancer Research Group, University Research Center, University of Antioquia, UdeA, Medellín, Colombia
| | - Angélica María Forero
- Club Noel Children's Clinical Foundation, Cali, Colombia
- Pediatrics Graduate Program, School of Medicine, University Libre Sectional Cali, Cali, Colombia
| | - Yulieth Alexandra Zúñiga
- Genetics, Regeneration and Cancer Research Group, University Research Center, University of Antioquia, UdeA, Medellín, Colombia
| | - María Eugenia Cuastumal
- Club Noel Children's Clinical Foundation, Cali, Colombia
- Pediatrics Graduate Program, School of Medicine, University Libre Sectional Cali, Cali, Colombia
| | - Leidy Johanna Acevedo
- Basic and Applied Microbiology Research Group, School of Microbiology, University of Antioquia, UdeA, Medellín, Colombia
| | - Álvaro de Jesús Molina
- Club Noel Children's Clinical Foundation, Cali, Colombia
- Pediatrics Graduate Program, School of Medicine, University Libre Sectional Cali, Cali, Colombia
| | - Johan Alexis Bolivar
- Genetics, Regeneration and Cancer Research Group, University Research Center, University of Antioquia, UdeA, Medellín, Colombia
| | - Alejandro Gómez-Mejia
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Molecular Genetics and Infection Biology, Center for Functional Genomics of Microbes, Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, Greifswald, Germany
| | - Jessica Lorena Morales
- Basic and Applied Microbiology Research Group, School of Microbiology, University of Antioquia, UdeA, Medellín, Colombia
- Genetics, Regeneration and Cancer Research Group, University Research Center, University of Antioquia, UdeA, Medellín, Colombia
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Center for Functional Genomics of Microbes, Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, Greifswald, Germany
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Rivero-Calle I, Pardo Seco J, Raguindin PF, Alvez F, Gómez-Rial J, Salas A, Martinón Sanchez J, Martinón-Torres F. Routine infant vaccination of pneumococcal conjugate vaccines has decreased pneumonia across all age groups in Northern Spain. Hum Vaccin Immunother 2019; 16:1446-1453. [PMID: 31851569 DOI: 10.1080/21645515.2019.1690884] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Since the early 2000s, pneumococcal conjugate vaccines (PCVs) have been shown to be effective in the prevention of pneumonia and invasive pneumococcal diseases. In 2011, the Galician region incorporated PCV in the routine infant immunization, the very first stable program in Spain. We aim to assess direct and indirect benefits of PCV vaccination on all-cause pneumonia in the region across different age groups using an ecological study design. For this, we calculated the annual hospitalization rates using a hospital-based disease registry. We identified all-cause pneumonia, pneumococcal pneumonia and pneumococcal invasive diseases within the registry. Hospitalization rates were computed and compared across three study periods: pre-vaccination (1998-2003), early-vaccination (2005-2009) and routine-vaccination (2011-2015). Across Northern Spain, we identified 114,873 all-cause pneumonia hospitalizations, of which 24,808 were further diagnosed with pneumococcal pneumonia. The majority were elderly > 64 years (67.3%). Hospitalizations from all-cause pneumonia had a net increase from 20.6 (pre-PCV) and 21.4/10,000 (early) to 28.4/10,000 (routine) (+32.7%, p < .0001), this is attributed to the huge number of cases in the elderly age group. In contrast, a net reduction of incidence of hospitalized pneumococcal pneumonia was observed from 6.3/10,000 (pre-PCV) and 5.7/10,000 (early) to 2.4/10,000 (routine) cases (-57.9%, p < .0001). Thus, routine infant vaccination may have resulted to an overall decline of pneumococcal pneumonia in infants, as well as in elderly age groups. However, a paradoxical increase on all-cause pneumonia was observed in Galicia, mostly attributed to the growing number of cases in the elderly population.
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Affiliation(s)
- I Rivero-Calle
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group (GENVIP), Hospital Clínico Universitario and Universidad de Santiago de Compostela (USC) , Galicia, Spain.,Translational Pediatrics and Infectious Diseases, Department of Pediatrics, Hospital Clínico Universitario de Santiago de Compostela , Galicia, Spain
| | - J Pardo Seco
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group (GENVIP), Hospital Clínico Universitario and Universidad de Santiago de Compostela (USC) , Galicia, Spain
| | - P F Raguindin
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group (GENVIP), Hospital Clínico Universitario and Universidad de Santiago de Compostela (USC) , Galicia, Spain
| | - F Alvez
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group (GENVIP), Hospital Clínico Universitario and Universidad de Santiago de Compostela (USC) , Galicia, Spain
| | - J Gómez-Rial
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group (GENVIP), Hospital Clínico Universitario and Universidad de Santiago de Compostela (USC) , Galicia, Spain
| | - A Salas
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group (GENVIP), Hospital Clínico Universitario and Universidad de Santiago de Compostela (USC) , Galicia, Spain.,Unidad de Genética, Departamento de Anatomía Patológica y Ciencias Forenses, Instituto de Ciencias Forenses, Facultad de Medicina, Universidad de Santiago de Compostela, and GENPOB, Research Group, Instituto de Investigaciones Sanitarias (IDIS), Hospital Clínico Universitario de Santiago , Galicia, Spain
| | - J Martinón Sanchez
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group (GENVIP), Hospital Clínico Universitario and Universidad de Santiago de Compostela (USC) , Galicia, Spain.,Translational Pediatrics and Infectious Diseases, Department of Pediatrics, Hospital Clínico Universitario de Santiago de Compostela , Galicia, Spain
| | - F Martinón-Torres
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group (GENVIP), Hospital Clínico Universitario and Universidad de Santiago de Compostela (USC) , Galicia, Spain.,Translational Pediatrics and Infectious Diseases, Department of Pediatrics, Hospital Clínico Universitario de Santiago de Compostela , Galicia, Spain
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Identification of Pneumococcal Serotypes by PCR-Restriction Fragment Length Polymorphism. Diagnostics (Basel) 2019; 9:diagnostics9040196. [PMID: 31752204 PMCID: PMC6963424 DOI: 10.3390/diagnostics9040196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 11/30/2022] Open
Abstract
Streptococcus pneumoniae shows more than 90 capsular serotypes that can be distinguished by their reactivity against antisera. The main objective of this work was the development of a molecular method for serotyping without the use of antisera. A computer program containing an algorithm was used to search in a database for potentially useful enzymes for Restriction Fragment Length Polymorphism-RFLP typing, in order to maximize the discrimination between different serotypes. DNA sequences of 90 serotypes for the region between dexB and aliA genes were compiled, and a computer screening of restriction enzymes was performed. The wzg–wzh–wzd–wze region and Sse9I restriction predicted unique PCR-RFLP patterns for 39 serotypes and eight serogroups. A second restriction enzyme resolved fragment specific patterns for 25 serotypes. The method was tested with 98 serotype-unknown clinical isolates. PCR-RFLP analysis deduced correct serotypes that were confirmed by Quellung reaction for 78.5% of the isolates.
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Sanz Moreno JC, Ramos Blázquez B. Papel del estado de portador en el control de enfermedades infecciosas y su relación con la vacunación. REVISTA MADRILEÑA DE SALUD PÚBLICA 2019. [DOI: 10.36300/remasp.2019.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
El reservorio natural de Streptococcus pneumoniae,
Neisseria meningitidis y Bordetella pertussis es el ser
humano. De este modo, en caso de disponer de vacunas
efectivas que impidieran la colonización por estas bacterias
se podría interrumpir su transmisión.
La respuesta inmune frente a los antígenos capsulares
de Streptococcus pneumoniae condiciona el estado
de portador de los diferentes serotipos. La vacuna
neumocócica polisacárida 23 valente (PPV23) induce
una respuesta inmune T independiente que es de corta
duración y no previene la colonización. Por el contrario
las vacunas conjugadas 10 valente (PCV10V) y 13 valente
(PCV13) generan una inmunidad T dependiente que
si reduce la colonización por los serotipos incluidos en
su composición. Por este motivo las vacunas conjugadas
proporcionan inmunidad de grupo.
La vacunación de adolescentes frente a Neisseria menigintidis
puede modificar el patrón de transmisión de la
infección con una reducción de la incidencia en niños. En
la actualidad se dispone de vacunas conjugadas frente
a meningococo C, conjugadas tetravalantes frente a los
serogrupos ACWY y de proteínas recombinantes frente a
meningococo B. La inmunidad de grupo generada por vacunas
conjugadas ha sido demostrada para Neisseria menigintidis
C. Desafortunadamente existe escasa evidencia
del impacto de las vacunas frente a meningococo B en la
reducción del estado de portador entre adultos jóvenes.
La infección natural por Bordetella pertussis estimula la
producción de linfocitos T de memoria e induce una intensa
respuesta de IgA secretora en la nasofaringe. En
contraste con la infección natural y con las vacunas de
células completas las actuales vacunas acelulares, no
generan inmunidad en mucosas y no otorgan inmunidad
de grupo. En un intento de resolver este problema se
están desarrollando vacunas alternativas frente a Bordetella
pertussis como las nuevas de células completas y
las vivas atenuadas.
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Affiliation(s)
- Juan Carlos Sanz Moreno
- Unidad de Microbiología Clínica. Laboratorio Regional de Salud Pública. Dirección General de Salud Pública. Consejería de Sanidad. Comunidad de Madrid
| | - Belén Ramos Blázquez
- Unidad de Microbiología Clínica. Laboratorio Regional de Salud Pública. Dirección General de Salud Pública. Consejería de Sanidad. Comunidad de Madrid
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Malmgren A, Biswanger K, Lundqvist A, Zaoutis T. Education, decision support, feedback and a minor reward: a novel antimicrobial Stewardship intervention in a Swedish paediatric emergency setting. Infect Dis (Lond) 2019; 51:559-569. [PMID: 31088317 DOI: 10.1080/23744235.2019.1606933] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background: Sweden enjoys a favourable situation with regard to antimicrobial resistance. However, healthcare costs are expected to increase exponentially, along with increased morbidity and mortality, due to the emergence of resistant bacterial strains. Our aim was to design an antimicrobial stewardship programme suitable for Scandinavian settings. Methods: A quasi-experimental pre-post study was conducted in a Swedish paediatric emergency department, evaluating adherence to national guidelines for acute otitis media and acute tonsillitis. The programme consisted of educational outreach, decision support, feedback, and a minor reward upon reaching a pre-defined adherence rate. Results: The largest impact, significant for both diagnoses, was on the practice of refraining from antibiotic use when recommended. The other variables evaluated showed no significant improvement for either condition; however, in most cases, pre-interventional adherence was already high. Conclusions: This relatively easily implementable ASP intervention showed a significant effect on correctly refraining from the use of antibiotics. Previous interventions in Scandinavia either failed to accomplish this or have been more logistically difficult. The combination of education, decision support, email-based feedback and a minor reward, offers an alternative. Future research will be needed to assess whether the result is sustainable, as well as to identify additional barriers to the judicious use of antibiotics not addressed in this study.
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Affiliation(s)
- Annika Malmgren
- a Department of Pediatric Medicine , Queen Silvia Children's Hospital , Gothenburg , Sweden
| | - Karin Biswanger
- b Department of Pediatric Medicine , Södra Älvsborg Hospital , Borås , Sweden
| | - Anders Lundqvist
- c Department of Infectious Diseases , Södra Älvsborg Hospital , Borås , Sweden
| | - Theoklis Zaoutis
- d Division of Infectious Diseases and the Center for Pediatric Clinical Effectiveness , Children's Hospital of Philadelphia , Philadelphia , PA , USA
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Abaye G, Fekadu H, Haji K, Alemu D, Anjulo AA, Yadate DT. Prevalence and risk factors of pneumococcal nasopharyngeal carriage in healthy children attending kindergarten, in district of Arsi Zone, South East, Ethiopia. BMC Res Notes 2019; 12:253. [PMID: 31064380 PMCID: PMC6505268 DOI: 10.1186/s13104-019-4283-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 04/25/2019] [Indexed: 11/13/2022] Open
Abstract
Objective S. pneumoniae responsible for a range of respiratory infections from uncomplicated to severe invasive pneumococcal disease. Nasopharyngeal specimens were collected from children attending kindergarten and aged ≤ 6 years from February, 2017 to June, 2017 to assess the nasopharyngeal carriage and antimicrobial susceptibility pattern of S. pneumoniae. Parents of children interviewed using questionnaire and check list to identify associated factors. An antimicrobial susceptibility test performed using disk diffusion method. Results Overall pneumococcal carriage were 18.4% (88/477). No significant variation in colonization based on sex and age of children. Children living with siblings (1–2) < 6 years in household (adjusted odd ratio = 16.06; 95% confidence interval 6.21–41.55) and > 5 person per household (adjusted odd ratio = 3.27; 95% confidence interval 1.50–7.14) were associated with higher S. pneumoniae carriage. Non- exclusive breast feeding (adjust odd ratio = 6.00; 95% confidence interval 3.33–10.80) and horse cart transportation (adjusted odd ratio = 2.75; 95% confidence interval 1.05–7.22) increases carriage. S. pneumoniae showed 21 (23.9%) resistance to erythromycin, 18 (20.4%) to amoxicillin, 13 (15.0%) to penicillin, and the least 1 (1.1%) to augmentin.
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Affiliation(s)
- Gizaw Abaye
- Department of Medical Laboratory Science, College of Health Sciences, Arsi University, Asella, Ethiopia.
| | - Hailu Fekadu
- Department of Public Health, College of Health Sciences, Arsi University, Asella, Ethiopia
| | - Kelili Haji
- Department of Anatomy, College of Health Sciences, Arsi University, Asella, Ethiopia
| | - Desalegn Alemu
- Department of Medical Laboratory Science, College of Health Sciences, Arsi University, Asella, Ethiopia
| | - Antehun Alemayehu Anjulo
- Department of Medical Laboratory, College of Health Sciences and Medicine, Wolaita Sodo University, Wolaita Sodo, Ethiopia
| | - Debela T Yadate
- Department of Physiology, College of Health Sciences, Arsi University, Asella, Ethiopia
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Kovács E, Sahin-Tóth J, Tóthpál A, Kristóf K, van der Linden M, Tirczka T, Dobay O. Vaccine-driven serotype-rearrangement is seen with latency in clinical isolates: Comparison of carried and clinical pneumococcal isolates from the same time period in Hungary. Vaccine 2019; 37:99-108. [DOI: 10.1016/j.vaccine.2018.11.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 11/08/2018] [Accepted: 11/12/2018] [Indexed: 01/09/2023]
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11
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Morales M, Ludwig G, Ercibengoa M, Esteva C, Sanchez-Encinales V, Alonso M, Muñoz-Almagro C, Marimón JM. Changes in the serotype distribution of Streptococcus pneumoniae causing otitis media after PCV13 introduction in Spain. PLoS One 2018; 13:e0209048. [PMID: 30562385 PMCID: PMC6298674 DOI: 10.1371/journal.pone.0209048] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/27/2018] [Indexed: 11/19/2022] Open
Abstract
One of the beneficial effects of pneumococcal conjugate vaccines (PCVs) has been a decrease in the incidence of non-invasive infections, such as otitis media (OM) caused by vaccine serotypes. In this study, we analyzed the epidemiology of pneumococcal OM before and after PCV13 introduction in 2010. Between 2008 and 2016, the middle ear exudates from 2653 children under 14 years of age with OM were studied in two Spanish provinces (Gipuzkoa and Barcelona), and S. pneumoniae was isolated in 235 (8.9%) of cases. The 204 available isolates were serotyped and distributed in three 3-year periods: one before and two after PCV13 introduction (early and late post-PCV13). A significant decrease in the rate of OM caused by S. pneumoniae was observed mainly due to a decrease in infections caused by all PCV13 serotypes, although exceptions were observed including the persistence of serotype 3 in Gipuzkoa and a weak re-emergence of serotype 19F in both regions. The rate and diversity of non-PCV13 serotypes increased in both regions and an emerging clone causing OM was detected in each region: serotype 23B ST2372 in Gipuzkoa and serotype 11A ST838/ST6521 in Barcelona. The introduction of PCV13 has been followed by a change in the epidemiology of pneumococcal OM, with a decrease in the rate of vaccine serotypes accompanied by an increase in the diversity of non-vaccine serotype and the clonal spreading of different single clones in each region.
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Affiliation(s)
- María Morales
- Donostia University Hospital–Biodonostia Health Research Institute, Donostia-San Sebastian, Spain
- CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
| | - Guillermo Ludwig
- Molecular Microbiology Department, Institut de Recerca Sant Joan de Déu, Sant Joan de Déu University Hospital, Barcelona, Spain
| | - Maria Ercibengoa
- CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
- Preventive Medicine and Health Public Department, University of the Basque Country (UPV/EHU), Donostia-San Sebastian, Spain
| | - Cristina Esteva
- Molecular Microbiology Department, Institut de Recerca Sant Joan de Déu, Sant Joan de Déu University Hospital, Barcelona, Spain
- CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
| | | | - Marta Alonso
- Donostia University Hospital–Biodonostia Health Research Institute, Donostia-San Sebastian, Spain
- CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
| | - Carmen Muñoz-Almagro
- Molecular Microbiology Department, Institut de Recerca Sant Joan de Déu, Sant Joan de Déu University Hospital, Barcelona, Spain
- CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
- School of Medicine, Universitat Internacional de Catalunya, Barcelona, Spain
| | - José Maria Marimón
- Donostia University Hospital–Biodonostia Health Research Institute, Donostia-San Sebastian, Spain
- CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
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12
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Wouters I, Van Heirstraeten L, Desmet S, Blaizot S, Verhaegen J, Goossens H, Van Damme P, Malhotra-Kumar S, Theeten H. Nasopharyngeal s. pneumoniae carriage and density in Belgian infants after 9 years of pneumococcal conjugate vaccine programme. Vaccine 2017; 36:15-22. [PMID: 29180027 DOI: 10.1016/j.vaccine.2017.11.052] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 11/06/2017] [Accepted: 11/15/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND In Belgium, the infant pneumococcal conjugate vaccine (PCV) programme changed from PCV7 (2007-2011) to PCV13 (2011-2015) and to PCV10 (2015-2016). A 3-year nasopharyngeal carriage study was initiated during the programme switch in 2016. Main objective of the year 1 assessment was to obtain a baseline measurement of pneumococcal carriage prevalence, carriage density, serotype distribution and antibiotic resistance. MATERIALS/METHODS Two infant populations aged 6-30 months and without use of antibiotics in the seven days prior to sampling were approached: (1) attending one of 85 randomly selected day-care centres (DCC); (2) presenting with AOM at study-trained general practitioners and paediatricians. Demographic and clinical characteristics were documented and a single nasopharyngeal swab was taken. S. pneumoniae were cultured, screened for antibiotic resistance and serotyped, and quantitative Taqman real-time PCR (qRT-PCR) targeting LytA was performed. RESULTS Culture-based (DCC: 462/760; 60.8% - AOM: 27/39; 69.2%) and LytA-based (DCC: 603/753; 80.1% - AOM: 32/39; 82.1%) carriage prevalence was high. Average pneumococcal DNA load in LytA-positive day-care samples was 6.5 × 106 copies/µl (95%CI = 3.9-9.2 × 106, median = 3.5 × 105); DNA load was positively associated with signs of common cold and negatively with previous antibiotic use. Culture-based frequency of 13 pneumococcal vaccine (PCV) serotypes was 5.4% in DCC and 7.7% in AOM, with 19F and 14 being most frequent, and frequencies below 0.5% for serotypes 3, 6A, 19A in both populations. Predominant non-PCV serotypes were 23B and 23A in day-care and 11A in infants with AOM. In day-care, resistance to penicillin was rare (<0.5%) and absent against levofloxacin; 32.7% and 16.9% isolates were cotrimoxazole- and erythromycin-resistant respectively. CONCLUSION Four years after PCV13 introduction in the vaccination programme, PCV13 serotype carriage was rare in infants throughout Belgium and penicillin resistance was rare. Continued surveillance in the context of a PCV programme switch is necessary.
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Affiliation(s)
- Ine Wouters
- Centre for the Evaluation of Vaccination, Vaccine and Infectious Disease Institute, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, 2610 Wilrijk, Belgium.
| | - Liesbet Van Heirstraeten
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Stefanie Desmet
- Reference Centre for Pneumococci, University Hospitals Leuven, Campus Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium
| | - Stéphanie Blaizot
- Centre for Health Economics Research and Modelling Infectious Diseases, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Jan Verhaegen
- Reference Centre for Pneumococci, University Hospitals Leuven, Campus Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium
| | - Herman Goossens
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Pierre Van Damme
- Centre for the Evaluation of Vaccination, Vaccine and Infectious Disease Institute, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Surbhi Malhotra-Kumar
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Heidi Theeten
- Centre for the Evaluation of Vaccination, Vaccine and Infectious Disease Institute, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, 2610 Wilrijk, Belgium
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13
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Raman R, Sankar J, Putlibai S, Raghavan V. Demographic Profile of Healthy Children with Nasopharyngeal Colonisation of Streptococcus pneumoniae: A Research Paper. Indian J Med Microbiol 2017; 35:607-609. [DOI: 10.4103/ijmm.ijmm_15_347] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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14
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Wright MS, McCorrison J, Gomez AM, Beck E, Harkins D, Shankar J, Mounaud S, Segubre-Mercado E, Mojica AMR, Bacay B, Nzenze SA, Kimaro SZM, Adrian P, Klugman KP, Lucero MG, Nelson KE, Madhi S, Sutton GG, Nierman WC, Losada L. Strain Level Streptococcus Colonization Patterns during the First Year of Life. Front Microbiol 2017; 8:1661. [PMID: 28932211 PMCID: PMC5592222 DOI: 10.3389/fmicb.2017.01661] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/16/2017] [Indexed: 01/20/2023] Open
Abstract
Pneumococcal pneumonia has decreased significantly since the implementation of the pneumococcal conjugate vaccine (PCV), nevertheless, in many developing countries pneumonia mortality in infants remains high. We have undertaken a study of the nasopharyngeal (NP) microbiome during the first year of life in infants from The Philippines and South Africa. The study entailed the determination of the Streptococcus sp. carriage using a lytA qPCR assay, whole metagenomic sequencing, and in silico serotyping of Streptococcus pneumoniae, as well as 16S rRNA amplicon based community profiling. The lytA carriage in both populations increased with infant age and lytA+ samples ranged from 24 to 85% of the samples at each sampling time point. We next developed informatic tools for determining Streptococcus community composition and pneumococcal serotype from metagenomic sequences derived from a subset of longitudinal lytA-positive Streptococcus enrichment cultures from The Philippines (n = 26 infants, 50% vaccinated) and South African (n = 7 infants, 100% vaccinated). NP samples from infants were passaged in enrichment media, and metagenomic DNA was purified and sequenced. In silico capsular serotyping of these 51 metagenomic assemblies assigned known serotypes in 28 samples, and the co-occurrence of serotypes in 5 samples. Eighteen samples were not typeable using known serotypes but did encode for capsule biosynthetic cluster genes similar to non-encapsulated reference sequences. In addition, we performed metagenomic assembly and 16S rRNA amplicon profiling to understand co-colonization dynamics of Streptococcus sp. and other NP genera, revealing the presence of multiple Streptococcus species as well as potential respiratory pathogens in healthy infants. A range of virulence and drug resistant elements were identified as circulating in the NP microbiomes of these infants. This study revealed the frequent co-occurrence of multiple S. pneumoniae strains along with Streptococcus sp. and other potential pathogens such as S. aureus in the NP microbiome of these infants. In addition, the in silico serotype analysis proved powerful in determining the serotypes in S. pneumoniae carriage, and may lead to developing better targeted vaccines to prevent invasive pneumococcal disease (IPD) in these countries. These findings suggest that NP colonization by S. pneumoniae during the first years of life is a dynamic process involving multiple serotypes and species.
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Affiliation(s)
| | | | | | - Erin Beck
- J. Craig Venter InstituteRockville, MD, United States
| | - Derek Harkins
- J. Craig Venter InstituteRockville, MD, United States
| | - Jyoti Shankar
- J. Craig Venter InstituteRockville, MD, United States
| | | | | | | | - Brian Bacay
- Research Institute of Tropical MedicineMuntinlupa City, Philippines
| | - Susan A Nzenze
- Respiratory and Meningeal Pathogens Research UnitSoweto, South Africa
| | - Sheila Z M Kimaro
- Respiratory and Meningeal Pathogens Research UnitSoweto, South Africa
| | - Peter Adrian
- Respiratory and Meningeal Pathogens Research UnitSoweto, South Africa
| | - Keith P Klugman
- Respiratory and Meningeal Pathogens Research UnitSoweto, South Africa
| | - Marilla G Lucero
- Research Institute of Tropical MedicineMuntinlupa City, Philippines
| | | | - Shabir Madhi
- Respiratory and Meningeal Pathogens Research UnitSoweto, South Africa
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15
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Marimón JM, Morales M, Gamen S, Manrique A, Ercibengoa M, Cilla G. A reverse-hybridization test for the identification of 76 pneumococcal serotypes, 42 individually and 34 in pairs. J Microbiol Methods 2017; 143:13-16. [PMID: 28818600 DOI: 10.1016/j.mimet.2017.08.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/01/2017] [Accepted: 08/12/2017] [Indexed: 10/19/2022]
Abstract
The S. PneumoStrip test is a recently developed reverse hybridization strip-based commercial assay that allows for the identification of 76 pneumococcal serotypes, 42 individually and 34 in pairs, according to their specific gene sequences. The test was validated with reference strains of 92 different pneumococcal serotypes and with a selection of 75 clinical isolates representing 55 serotypes, showing 100% sensitivity and specificity. The test was also applied to 64 pneumococcal invasive isolates (23 different serotypes) consecutively collected between June 2016 and March 2017, with 60 (93.8%) being serotyped. Four isolates belonging to serotypes 13, 29, and 35B (2 isolates), which are not included in the test, did not produce a hybridization signal with serotype specific probes. The identification of most serotypes causing invasive pneumococcal disease together with the simplicity of performance and results interpretation, and the use of routine laboratory equipment make this test very suitable for most clinical and research laboratories.
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Affiliation(s)
- José M Marimón
- Microbiology Department, Hospital Universitario Donostia-Instituto de Investigación Sanitaria Biodonostia, San Sebastián, Spain; Biomedical Research Center Network for Respiratory Diseases (CIBERES), Madrid, Spain.
| | - María Morales
- Biomedical Research Center Network for Respiratory Diseases (CIBERES), Madrid, Spain
| | | | | | - María Ercibengoa
- Biomedical Research Center Network for Respiratory Diseases (CIBERES), Madrid, Spain
| | - Gustavo Cilla
- Microbiology Department, Hospital Universitario Donostia-Instituto de Investigación Sanitaria Biodonostia, San Sebastián, Spain; Biomedical Research Center Network for Respiratory Diseases (CIBERES), Madrid, Spain
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16
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Competitive Dominance within Biofilm Consortia Regulates the Relative Distribution of Pneumococcal Nasopharyngeal Density. Appl Environ Microbiol 2017; 83:AEM.00953-17. [PMID: 28576759 DOI: 10.1128/aem.00953-17] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 05/25/2017] [Indexed: 12/15/2022] Open
Abstract
Streptococcus pneumoniae is a main cause of child mortality worldwide, but strains also asymptomatically colonize the upper airways of most children and form biofilms. Recent studies have demonstrated that ∼50% of colonized children carry at least two different serotypes (i.e., strains) in the nasopharynx; however, studies of how strains coexist are limited. In this work, we investigated the physiological, genetic, and ecological requirements for the relative distribution of densities, and spatial localization, of pneumococcal strains within biofilm consortia. Biofilm consortia were prepared with vaccine type strains (i.e., serotype 6B [S6B], S19F, or S23F) and strain TIGR4 (S4). Experiments first revealed that the relative densities of S6B and S23F were similar in biofilm consortia. The density of S19F strains, however, was reduced to ∼10% in biofilm consortia, including either S6B, S23F, or TIGR4, in comparison to S19F monostrain biofilms. Reduction of S19F density within biofilm consortia was also observed in a simulated nasopharyngeal environment. Reduction of relative density was not related to growth rates, since the Malthusian parameter demonstrated similar rates of change of density for most strains. To investigate whether quorum sensing (QS) regulates relative densities in biofilm consortia, two different mutants were prepared: a TIGR4ΔluxS mutant and a TIGR4ΔcomC mutant. The density of S19F strains, however, was similarly reduced when consortia included TIGR4, TIGR4ΔluxS, or TIGR4ΔcomC Moreover, production of a different competence-stimulating peptide (CSP), CSP1 or CSP2, was not a factor that affected dominance. Finally, a mathematical model, confocal experiments, and experiments using Transwell devices demonstrated physical contact-mediated control of pneumococcal density within biofilm consortia.IMPORTANCEStreptococcus pneumoniae kills nearly half a million children every year, but it also produces nasopharyngeal biofilm consortia in a proportion of asymptomatic children, and these biofilms often contain two strains (i.e., serotypes). In our study, we investigated how strains coexist within pneumococcal consortia produced by vaccine serotypes S4, S6B, S19F, and S23F. Whereas S6B and S23F shared the biofilm consortium, our studies demonstrated reduction of the relative density of S19F strains, to ∼10% of what it would otherwise be if alone, in consortial biofilms formed with S4, S6B, or S23F. This dominance was not related to increased fitness when competing for nutrients, nor was it regulated by quorum-sensing LuxS/AI-2 or Com systems. It was demonstrated, however, to be enhanced by physical contact rather than by a product(s) secreted into the supernatant, as would naturally occur in the semidry nasopharyngeal environment. Competitive interactions within pneumococcal biofilm consortia regulate nasopharyngeal density, a risk factor for pneumococcal disease.
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17
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Long Persistence of a Streptococcus pneumoniae 23F Clone in a Cystic Fibrosis Patient. mSphere 2017; 2:mSphere00201-17. [PMID: 28596991 PMCID: PMC5463027 DOI: 10.1128/msphere.00201-17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Accepted: 05/01/2017] [Indexed: 02/07/2023] Open
Abstract
Streptococcus pneumoniae is a common resident in the human nasopharynx. However, carriage can result in severe diseases due to a unique repertoire of pathogenicity factors that are rare in closely related commensal streptococci. We investigated a penicillin-resistant S. pneumoniae clone of serotype 23F isolated from a cystic fibrosis patient on multiple occasions over an unusually long period of over 3 years that was present without causing disease. Genome comparisons revealed an apparent nonfunctional pneumococcus-specific gene encoding a hyaluronidase, supporting the view that this enzyme adds to the virulence potential of the bacterium. The 23F clone harbored unique mosaic genes encoding penicillin resistance determinants, the product of horizontal gene transfer involving the commensal S. mitis as donor species. Sequences identical to one such mosaic gene were identified in an S. mitis strain from the same patient, suggesting that in this case S. pneumoniae played the role of donor. Streptococcus pneumoniae isolates of serotype 23F with intermediate penicillin resistance were recovered on seven occasions over a period of 37 months from a cystic fibrosis patient in Berlin. All isolates expressed the same multilocus sequence type (ST), ST10523. The genome sequences of the first and last isolates, D122 and D141, revealed the absence of two phage-related gene clusters compared to the genome of another ST10523 strain, D219, isolated earlier at a different place in Germany. Genomes of all three strains carried the same novel mosaic penicillin-binding protein (PBP) genes, pbp2x, pbp2b, and pbp1a; these genes were distinct from those of other penicillin-resistant S. pneumoniae strains except for pbp1a of a Romanian S. pneumoniae isolate. All PBPs contained mutations that have been associated with the penicillin resistance phenotype. Most interestingly, a mosaic block identical to an internal pbp2x sequence of ST10523 was present in pbp2x of Streptococcus mitis strain B93-4, which was isolated from the same patient. This suggests interspecies gene transfer from S. pneumoniae to S. mitis within the host. Nearly all genes expressing surface proteins, which represent major virulence factors of S. pneumoniae and are typical for this species, were present in the genome of ST10523. One exception was the hyaluronidase gene hlyA, which contained a 12-nucleotide deletion within the promoter region and an internal stop codon. The lack of a functional hyaluronidase might contribute to the ability to persist in the host for an unusually long period of time. IMPORTANCEStreptococcus pneumoniae is a common resident in the human nasopharynx. However, carriage can result in severe diseases due to a unique repertoire of pathogenicity factors that are rare in closely related commensal streptococci. We investigated a penicillin-resistant S. pneumoniae clone of serotype 23F isolated from a cystic fibrosis patient on multiple occasions over an unusually long period of over 3 years that was present without causing disease. Genome comparisons revealed an apparent nonfunctional pneumococcus-specific gene encoding a hyaluronidase, supporting the view that this enzyme adds to the virulence potential of the bacterium. The 23F clone harbored unique mosaic genes encoding penicillin resistance determinants, the product of horizontal gene transfer involving the commensal S. mitis as donor species. Sequences identical to one such mosaic gene were identified in an S. mitis strain from the same patient, suggesting that in this case S. pneumoniae played the role of donor.
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18
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Càmara J, Marimón JM, Cercenado E, Larrosa N, Quesada MD, Fontanals D, Cubero M, Pérez-Trallero E, Fenoll A, Liñares J, Ardanuy C. Decrease of invasive pneumococcal disease (IPD) in adults after introduction of pneumococcal 13-valent conjugate vaccine in Spain. PLoS One 2017; 12:e0175224. [PMID: 28384325 PMCID: PMC5383258 DOI: 10.1371/journal.pone.0175224] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 03/22/2017] [Indexed: 02/01/2023] Open
Abstract
A prospective laboratory-based multicenter study that collected all adult invasive pneumococcal disease (IPD) episodes from 6 Spanish hospitals before (2008-2009) and after (2012-2013). The 13-valent pneumococcal conjugate vaccine (PCV13) licensure was conducted in order to analyze the impact of PCV13 introduction for children on adult IPD. A total of 1558 IPD episodes were detected. The incidence of IPD decreased significantly in the second period by -33.9% (95% CI, -40.3% to -26.8%). IPD due to PCV7 serotypes (-52.7%; 95% CI, -64.2% to -37.5%) and to PCV13 additional serotypes (-55.0% 95% CI, -62.0% to -46.7%) significantly decreased whereas IPD due to non-PCV13 serotypes remained stable (1.0% 95% CI, -12.9% to 17.2%). IPD due to all PCV13 additional serotypes significantly declined with the exception of serotype 3 (-11.3%; 95%CI -35.0% to 21.1%). IPD due to two non-PCV13 serotypes varied: serotype 6C that rose (301.6%; 95%CI, 92.7% to 733.3%, p<0.001), related to the expansion of ST3866C, and serotype 8 that decreased (-34.9%, 95%CI, -57.1 to -1.2, p = 0.049), related to a decline of the ST638. The recombinant clone ST652111A (variant of ST1569V) increased in frequency. The decrease of serotype 19A IPD was linked to a fall in those antibiotic susceptible clones. In the last period, rates of penicillin- and cefotaxime-resistance remained under 10% and 4%, respectively. Adult IPD decreased after the PCV13 introduction in Spain due to herd protection. The spread of multidrug resistant clones (ST3866C, ST652111A) related to non-PCV13 serotypes needs further surveillance.
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Affiliation(s)
- Jordi Càmara
- Hosp. Univ. de Bellvitge-Universitat de Barcelona-IDIBELL, L'Hospitalet de Llobregat, Spain
| | - José María Marimón
- Hosp. Univ. Donostia, Donostia-San Sebastián, Spain
- CIBER Enfermedades Respiratorias, Madrid, Spain
| | - Emilia Cercenado
- CIBER Enfermedades Respiratorias, Madrid, Spain
- Hosp. General Univ. Gregorio Marañón, Madrid, Spain
| | | | - María Dolores Quesada
- CIBER Enfermedades Respiratorias, Madrid, Spain
- H. U. Germans Trias i Pujol, Badalona, Spain
| | | | - Meritxell Cubero
- Hosp. Univ. de Bellvitge-Universitat de Barcelona-IDIBELL, L'Hospitalet de Llobregat, Spain
- CIBER Enfermedades Respiratorias, Madrid, Spain
| | - Emilio Pérez-Trallero
- Hosp. Univ. Donostia, Donostia-San Sebastián, Spain
- CIBER Enfermedades Respiratorias, Madrid, Spain
| | - Asunción Fenoll
- Laboratorio de Referencia de neumococo, ISCIII, Madrid, Spain
| | - Josefina Liñares
- Hosp. Univ. de Bellvitge-Universitat de Barcelona-IDIBELL, L'Hospitalet de Llobregat, Spain
- CIBER Enfermedades Respiratorias, Madrid, Spain
| | - Carmen Ardanuy
- Hosp. Univ. de Bellvitge-Universitat de Barcelona-IDIBELL, L'Hospitalet de Llobregat, Spain
- CIBER Enfermedades Respiratorias, Madrid, Spain
- * E-mail:
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PCV13-vaccinated children still carrying PCV13 additional serotypes show similar carriage density to a control group of PCV7-vaccinated children. Vaccine 2017; 35:945-950. [DOI: 10.1016/j.vaccine.2016.12.052] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 12/08/2016] [Accepted: 12/20/2016] [Indexed: 11/22/2022]
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20
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Caierão J, Sant'Anna FH, Hawkins P, Cunha GR, Mott M, Falci DR, d'Azevedo PA, McGee L, Dias C. Characteristics of serogroup 20 S.pneumoniae isolates from Brazil. BMC Infect Dis 2016; 16:418. [PMID: 27527077 PMCID: PMC4986405 DOI: 10.1186/s12879-016-1773-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/10/2016] [Indexed: 01/24/2023] Open
Abstract
Background Although serogroup 20 is not part of any conjugate pneumococcal vaccine, its serotype 20A, but not 20B, belongs to the polysaccharide 23-valent formula. Little is known about its clinical, laboratorial and epidemiological characteristics. Methods The purpose of this study was to evaluate the bacterial genotypes (by PFGE and MLST), clinical characteristics of patients (from review of medical records) and antimicrobial susceptibility of serogroup 20 isolates which were recovered from patients with invasive pneumococcal disease (IPD) from 2007 to 2012. Subtyping to determine 20A and 20B types was also performed by sequencing the genes of the cps locus. Results Sixteen isolates were genotyped and were highly related. All pneumococci were resistant to tetracycline and 31 % were non-susceptible to trimethoprim/sulfamethoxazole. Penicillin MIC ranged from 0.004 to 1 μg/mL and non-susceptibility (MIC ≥ 0.12 μg/mL) was observed in 5/16 isolates (31 %). All isolates belonged to subtype 20B. Most patients were male with a median age of 62 years and presented at least one underlying disease (mostly respiratory conditions). All isolates belonged to ST8889 and to a unique PFGE clone. Conclusions A high clonal occurrence of serotype 20B pneumococci recovered from patients with IPD in Brazil was observed. As a non-PCV10 serotype, selective pressure may be responsible for this unusual occurrence of serogroup 20. However, temporal variation effect should not be underestimated; therefore it is an issue that warrants continued monitoring.
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Affiliation(s)
- Juliana Caierão
- Basic Health Department, Federal University of Health Science of Porto Alegre, Porto Alegre, Brazil.
| | - Fernando Hayashi Sant'Anna
- Genetic Departament, Bioscience Institute, Center of Agricultural Microbiology Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Paulina Hawkins
- Rollins School of Public Health, Emory University, Atlanta, USA
| | - Gabriela Rosa Cunha
- Basic Health Department, Federal University of Health Science of Porto Alegre, Porto Alegre, Brazil
| | - Mariana Mott
- Basic Health Department, Federal University of Health Science of Porto Alegre, Porto Alegre, Brazil
| | | | - Pedro Alves d'Azevedo
- Basic Health Department, Federal University of Health Science of Porto Alegre, Porto Alegre, Brazil
| | - Lesley McGee
- Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, USA
| | - Cícero Dias
- Basic Health Department, Federal University of Health Science of Porto Alegre, Porto Alegre, Brazil
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Cocolonization of Pneumococcal Serotypes in Healthy Children Attending Day Care Centers: Molecular Versus Conventional Methods. Pediatr Infect Dis J 2016; 35:477-80. [PMID: 26808723 DOI: 10.1097/inf.0000000000001059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Pneumococci are common colonizer, especially of children, and cocolonization of different serotypes is an important factor for intraspecies genetic exchange. The aim of this study was to analyze pneumococcal carriage and serotype distribution in unvaccinated healthy children in Iceland and compare conventional culture methods and molecular methods using DNA extracted directly from the samples. METHODS Nasopharyngeal swabs were obtained from 514 children aged 2-6 year attending day care centers in Reykjavik in 2009. The swabs were selectively cultured for pneumococci and the isolates serotyped using latex agglutination. DNA was also extracted directly from the swabs and serotyped using a multiplex PCR panel designed to detect vaccine serotypes and the most commonly carried non-vaccine serotypes. RESULT Pneumococcal carriage was detected in 391 (76.1%) of the children using polymerase chain reaction (PCR) and in 371 (72.2%) using conventional methods. Cocolonization was detected in 92 (23.5%) of the carriers when PCR method was used and in 30 (8.1%) when conventional methods were used, detecting 500 and 401 strains, respectively (P < 0.0001). The most common serotypes were 23F, 19A, 6B, 6A and 19F, rates 13-8%. The number of isolates of serotypes included in the 10-valent and 13-valent vaccines and detected by PCR were 234 (58.4%) and 363 (90.5%), respectively and by conventional methods 186 (46.4%) and 293 (73.1%), respectively. CONCLUSION Cocolonization was detected in a fourth of the children carrying pneumococci using DNA extracted directly from nasopharyngeal swabs. The rate of carriage was very high, but no serotype dominated, and the children were commonly colonized by vaccine serotypes, especially cocolonized children.
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Menezes APDO, Azevedo J, Leite MC, Campos LC, Cunha M, Carvalho MDGS, Reis MG, Ko AI, Weinberger DM, Ribeiro G, Reis JN. Nasopharyngeal carriage of Streptococcus pneumoniae among children in an urban setting in Brazil prior to PCV10 introduction. Vaccine 2016; 34:791-7. [PMID: 26742946 PMCID: PMC4729601 DOI: 10.1016/j.vaccine.2015.12.042] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 11/26/2015] [Accepted: 12/16/2015] [Indexed: 11/21/2022]
Abstract
Information on pneumococcal carriage in the pre-vaccine period is essential to predict and assess the impact of PCV in settings where disease surveillance is particularly difficult. Therefore, we present data on pneumococcal carriage before the introduction of the 10-valent-pneumococcal conjugate vaccine (PCV10) in Brazil. We conducted a prospective study on a cohort of 203 children aged <5 years old, randomly selected in an urban community located in the periphery of the city of Salvador, Brazil and followed them from January/2008 to January/2009. Nasopharyngeal swabs were collected from each child at four times. In total, 721 swabs were collected, yielding a pneumococcal carriage prevalence of 55% (n=398). In multivariate analyses, the variables associated with carriage were having contact with three or more children <2 years old (OR, 2.00; 95% CI 1.33-2.89) and living in a house with an average of 3 residents per room (OR, 1.77; 95% CI 1.05-3.10). Also, white participants were more likely to be protected from colonization (OR, 0.52; 95% CI 0.29-0.93), and prevalence of carriage varied over time, with lower prevalence occurring from February to June (OR, 0.53; 95% CI 0.37-0.78) compared to July to January. Contact with children under 2 years of age and living in crowded housing also were associated with colonization by highly invasive serotypes, although this relationship was not significant. The most prevalent vaccine serotypes were 6A/B (25.4%), 19F (10.1%) and 14 (9.0%), while the most prevalent non-vaccine serotypes were 16F (4.8%), 15B/C (4.5%) and 6C/D (3.5%). Overall, 38.4% (153/398) of the isolates were non-susceptible to penicillin, and of those, 73.8% (113/153) were non-susceptible to trimethoprim/sulfamethoxazole. Colonization rate by PCV10 serotypes was 52.2%. Routine PCV10 vaccination can lead to significant changes in pneumococcal serotypes found in NP colonization, indicating a need for continued monitoring, especially in crowded settings, as occurs in Brazil's slums.
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Affiliation(s)
| | - Jailton Azevedo
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
| | - Mariela C Leite
- Faculdade de Farmácia, Universidade Federal da Bahia, Salvador, Brazil
| | - Leila C Campos
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
| | - Marcelo Cunha
- Escola Nacional de Saúde Pública, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | | | - Mitermayer G Reis
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
| | - Albert I Ko
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil; Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, USA
| | - Daniel M Weinberger
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, USA
| | - Guilherme Ribeiro
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil; Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador, Brazil
| | - Joice N Reis
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil; Faculdade de Farmácia, Universidade Federal da Bahia, Salvador, Brazil.
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Ziane H, Manageiro V, Ferreira E, Bektache S, Tazir M, Caniça M. Capsular typing of Streptococcus pneumoniae isolated in an Algerian hospital using a new multiplex PCR-based scheme. J Microbiol Methods 2015; 119:243-6. [PMID: 26546733 DOI: 10.1016/j.mimet.2015.11.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 11/03/2015] [Accepted: 11/03/2015] [Indexed: 11/18/2022]
Abstract
We developed a new sequential multiplex-PCR-based typing scheme (MPBTS) for pneumococcal capsular classification. The serogroup/type of 37 control isolates obtained by the Quellung reaction, MPBTS, and nucleotide sequencing, were fully concordant. The serogroups/types of 75 invasive isolates determined by MPBTS, presented 100% specificity and 96% sensitivity, when compared with the Quellung reaction.
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Affiliation(s)
- Hanifa Ziane
- Service de Microbiologie Clinique, Centre Hospitalo-Universitaire Mustapha Bacha, Faculté de Médecine, Algiers, Algeria
| | - Vera Manageiro
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal; CECA-ICETA, Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto University, Oporto, Portugal.
| | - Eugénia Ferreira
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal
| | - Soumia Bektache
- Service de Microbiologie Clinique, Centre Hospitalo-Universitaire Mustapha Bacha, Faculté de Médecine, Algiers, Algeria
| | - Mohamed Tazir
- Service de Microbiologie Clinique, Centre Hospitalo-Universitaire Mustapha Bacha, Faculté de Médecine, Algiers, Algeria
| | - Manuela Caniça
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal
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Gjini E, Valente C, Sá-Leão R, Gomes MGM. How direct competition shapes coexistence and vaccine effects in multi-strain pathogen systems. J Theor Biol 2015; 388:50-60. [PMID: 26471070 DOI: 10.1016/j.jtbi.2015.09.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 09/02/2015] [Accepted: 09/22/2015] [Indexed: 11/25/2022]
Abstract
We describe an integrated modeling framework for understanding strain coexistence in polymorphic pathogen systems. Previous studies have debated the utility of neutral formulations and focused on cross-immunity between strains as a major stabilizing mechanism. Here we convey that direct competition for colonization mediates stable coexistence only when competitive abilities amongst pathogen clones satisfy certain pairwise asymmetries. We illustrate our ideas with nested SIS models of single and dual colonization, applied to polymorphic pneumococcal bacteria. By fitting the models to cross-sectional prevalence data from Portugal (before and after the introduction of a seven-valent pneumococcal conjugate vaccine), we are able to not only statistically compare neutral and non-neutral epidemiological formulations, but also estimate vaccine efficacy, transmission and competition parameters simultaneously. Our study highlights that the response of polymorphic pathogen populations to interventions holds crucial information about strain interactions, which can be extracted by suitable nested modeling.
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Affiliation(s)
- Erida Gjini
- Instituto Gulbenkian de Ciência, Apartado 14, 2781-901 Oeiras, Portugal.
| | - Carina Valente
- Laboratory of Molecular Microbiology of Human Pathogens, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Raquel Sá-Leão
- Laboratory of Molecular Microbiology of Human Pathogens, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | - M Gabriela M Gomes
- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade de Porto, Portugal; Instituto de Matemática e Estatística, Universidade de São Paulo, Brazil; Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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25
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Kamng'ona AW, Hinds J, Bar-Zeev N, Gould KA, Chaguza C, Msefula C, Cornick JE, Kulohoma BW, Gray K, Bentley SD, French N, Heyderman RS, Everett DB. High multiple carriage and emergence of Streptococcus pneumoniae vaccine serotype variants in Malawian children. BMC Infect Dis 2015; 15:234. [PMID: 26088623 PMCID: PMC4474563 DOI: 10.1186/s12879-015-0980-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 06/08/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Carriage of either single or multiple pneumococcal serotypes (multiple carriage) is a prerequisite for developing invasive pneumococcal disease. However, despite the reported high rates of pneumococcal carriage in Malawi, no data on carriage of multiple serotypes has been reported previously. Our study provides the first description of the prevalence of multiple pneumococcal carriage in Malawi. METHODS The study was conducted in Blantyre and Karonga districts in Malawi, from 2008 to 2012. We recruited 116 children aged 0-13 years. These children were either HIV-infected (N = 44) or uninfected (N = 72). Nasopharyngeal samples were collected using sterile swabs. Pneumococcal serotypes in the samples were identified by microarray. Strains that could not be typed by microarray were sequenced to characterise possible genetic alterations within the capsular polysaccharide (CPS) locus. RESULTS The microarray identified 179 pneumococcal strains (from 116 subjects), encompassing 43 distinct serotypes and non-typeable (NT) strains. Forty per cent (46/116) of children carried multiple serotypes. Carriage of vaccine type (VT) strains was higher (p = 0.028) in younger (0-2 years) children (71 %, 40/56) compared to older (3-13 years) children (50 %, 30/60). Genetic variations within the CPS locus of known serotypes were observed in 19 % (34/179) of the strains identified. The variants included 13-valent pneumococcal conjugate vaccine (PCV13) serotypes 6B and 19A, and the polysaccharide vaccine serotype 20. Serotype 6B variants were the most frequently isolated (47 %, 16/34). Unlike the wild type, the CPS locus of the 6B variants contained an insertion of the licD-family phosphotransferase gene. The CPS locus of 19A- and 20-variants contained an inversion in the sugar-biosynthesis (rmlD) gene and a 717 bp deletion within the transferase (whaF) gene, respectively. CONCLUSIONS The high multiple carriage in Malawian children provides opportunities for genetic exchange through horizontal gene transfer. This may potentially lead to CPS locus variants and vaccine escape. Variants reported here occurred naturally, however, PCV13 introduction could exacerbate the CPS genetic variations. Further studies are therefore recommended to assess the invasive potential of these variants and establish whether PCV13 would offer cross-protection. We have shown that younger children (0-2 years) are a reservoir of VT serotypes, which makes them an ideal target for vaccination.
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Affiliation(s)
- Arox W Kamng'ona
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Biochemistry Department, University of Malawi, College of Medicine, Blantyre, Malawi. .,Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.
| | - Jason Hinds
- Division of Clinical Sciences, St George's, University of London, London, UK.
| | - Naor Bar-Zeev
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.
| | - Katherine A Gould
- Division of Clinical Sciences, St George's, University of London, London, UK.
| | - Chrispin Chaguza
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.
| | - Chisomo Msefula
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Microbiology Department, University of Malawi, College of Medicine, Blantyre, Malawi.
| | - Jennifer E Cornick
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.
| | - Benard W Kulohoma
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Institute of Infection and Global Health, University of Liverpool, Liverpool, UK. .,International Centre for Insect Physiology and Ecology, Nairobi, Kenya.
| | - Katherine Gray
- Biochemistry Department, University of Malawi, College of Medicine, Blantyre, Malawi.
| | - Stephen D Bentley
- Pathogen Genomics, Wellcome Trust Sanger Institute, Cambridge, UK. .,Department of Medicine, University of Cambridge, Cambridge, UK.
| | - Neil French
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Institute of Infection and Global Health, University of Liverpool, Liverpool, UK. .,Malawi Epidemiology and Intervention Research Unit (MEIRU), Karonga, Malawi.
| | - Robert S Heyderman
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Liverpool School of Tropical Medicine, Liverpool, UK.
| | - Dean B Everett
- Microbes, Immunity and Vaccines, Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.
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Single-plex quantitative assays for the detection and quantification of most pneumococcal serotypes. PLoS One 2015; 10:e0121064. [PMID: 25798884 PMCID: PMC4370668 DOI: 10.1371/journal.pone.0121064] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 01/27/2015] [Indexed: 12/04/2022] Open
Abstract
Streptococcus pneumoniae globally kills more children than any other infectious disease every year. A prerequisite for pneumococcal disease and transmission is colonization of the nasopharynx. While the introduction of pneumococcal conjugate vaccines has reduced the burden of pneumococcal disease, understanding the impact of vaccination on nasopharyngeal colonization has been hampered by the lack of sensitive quantitative methods for the detection of >90 known S. pneumoniae serotypes. In this work, we developed 27 new quantitative (q)PCR reactions and optimized 26 for a total of 53 qPCR reactions targeting pneumococcal serotypes or serogroups, including all vaccine types. Reactions proved to be target-specific with a limit of detection of 2 genome equivalents per reaction. Given the number of probes required for these assays and their unknown shelf-life, the stability of cryopreserved reagents was evaluated. Our studies demonstrate that two-year cryopreserved probes had similar limit of detection as freshly-diluted probes. Moreover, efficiency and limit of detection of 1-month cryopreserved, ready-to-use, qPCR reaction mixtures were similar to those of freshly prepared mixtures. Using these reactions, our proof-of-concept studies utilizing nasopharyngeal samples (N=30) collected from young children detected samples containing ≥2 serotypes/serogroups. Samples colonized by multiple serotypes/serogroups always had a serotype that contributes at least 50% of the pneumococcal load. In addition, a molecular approach called S6-q(PCR)2 was developed and proven to individually detect and quantify epidemiologically-important serogroup 6 strains including 6A, 6B, 6C and 6D. This technology will be useful for epidemiological studies, diagnostic platforms and to study the pneumobiome.
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27
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Tóthpál A, Kardos S, Laub K, Nagy K, Tirczka T, van der Linden M, Dobay O. Radical serotype rearrangement of carried pneumococci in the first 3 years after intensive vaccination started in Hungary. Eur J Pediatr 2015; 174:373-81. [PMID: 25178897 DOI: 10.1007/s00431-014-2408-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 08/06/2014] [Accepted: 08/19/2014] [Indexed: 11/25/2022]
Abstract
UNLABELLED Streptococcus pneumoniae is responsible for a significant amount of morbidity and mortality worldwide. Healthy carriers, mainly young children, are the most important sources of infections. In the current study, we aimed to determine the changes that have occurred since the introduction of PCV-7 in Hungary. Nasal specimens were collected from 1,022 healthy children aged 3-6 years attending day-care centres. After thorough identification, pneumococcal isolates were serotyped, and their antibiotic sensitivity was determined. The carriage rate was found to be 34.9%. A huge serotype rearrangement was detected compared to earlier results, with the previously leading serotype 14 having completely disappeared. Serotypes 11A, 35F, 19A, 6B, 15B, 3 and 38 were most prevalent, and 29 different types were identified in total. The PCV-7 types were responsible for 16.5% of all serotypes, and 36.0% are not covered by any pneumococcal vaccines. The isolates were sensitive to most tested antibiotics, except erythromycin (resistance was 21.6%). Only one penicillin-resistant strain was found. The newly and rapidly emerging non-vaccine serotypes are much more sensitive, except serotype 19A. CONCLUSION Due to PCV vaccination, a complete serotype arrangement occurred also in Hungary. The old "paediatric" serotypes were replaced by serotypes 11A, 35F, 19A, 6B, 15B, 3 and 38.
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Affiliation(s)
- Adrienn Tóthpál
- Institute of Medical Microbiology, Semmelweis University, Budapest, Nagyvárad tér 4, 1089, Hungary,
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Boada A, Almeda J, Grenzner E, Pons-Vigués M, Morros R, Juvé R, Simonet PJ, den Heijer CDJ, Bolíbar B. [Prevalence of nasal carriage of Staphylococcus aureus and Streptococcus pneumoniae in Primary Care and factors associated with colonization]. Enferm Infecc Microbiol Clin 2015; 33:451-7. [PMID: 25617018 DOI: 10.1016/j.eimc.2014.10.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 10/10/2014] [Accepted: 10/24/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVE To determine (i) the prevalence of Staphylococcus aureus (S.aureus) and Streptococcus pneumoniae (S.pneumoniae) nasal carriage in Primary Health Care patients in area of Barcelona, and (ii) the factors associated with S.aureus and S.pneumoniae colonization. METHODS Multi-center cross-sectional study conducted in 2010-2011 with the participation of 27 Primary Health Care professionals. Nasopharyngeal swabs were obtained from 3,969 patients over 4 years of age who did not present with any sign of infection. DEPENDENT VARIABLES S.aureus and/or S.pneumoniae carrier state. INDEPENDENT VARIABLES socio-demographic characteristics, health status, vaccination status, occupation, and living with children. A descriptive analysis was performed. The prevalence of carriers of S.aureus and/or S.pneumoniae was calculated and logistic regression models were adjusted by age. RESULTS In children from 4 to 14 years old, the prevalence of S.aureus carriers was 35.7%, of S.pneumoniae 27.1%, and 5.8% were co-colonized. In adults older than 14 years old, the prevalence was 17.8%, 3.5%, and 0.5%, respectively. In children, S.aureus carrier state was inversely associated with S.pneumoniae carrier state; S.pneumoniae was associated with younger age, and inversely associated with S.aureus carrier state. In adults, being a carrier of S.aureus was associated with male gender, younger age, and a health-related occupation, whereas S.pneumoniae carrier state was associated with living with children under 6 years of age. The proportion of co-colonized carriers was low (1.0%). CONCLUSIONS The proportion of S.aureus and S.pneumoniae carriers was higher in children than in adults. Age was the only factor associated with healthy carrier status for S.aureus and for S.pneumoniae.
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Affiliation(s)
- Albert Boada
- Equip d'Atenció Primària Guinardó Baix (Barcelona 7-G), Gerència d'Àmbit d'Atenció Primària Barcelona Ciutat, Institut Català de la Salut, Barcelona, España; Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Barcelona, España
| | - Jesús Almeda
- Unitat de Suport a la Recerca Metropolitana Sud, Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Cornellà de Llobregat, España; CIBER de Epidemiología y Salud Pública (CIBERESP), Barcelona, España
| | - Elisabet Grenzner
- Laboratori Clínic l'Hospitalet (ICS Metropolitana Sud), L'Hospitalet de Llobregat, Barcelona, España; Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Barcelona, España
| | - Mariona Pons-Vigués
- Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Barcelona, España; Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, España
| | - Rosa Morros
- Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Barcelona, España; Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, España
| | - Rosa Juvé
- Laboratori Clínic Bon Pastor, Institut Català de la Salut, Barcelona, España; Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Barcelona, España
| | - Pere J Simonet
- Unitat de Suport a la Recerca Metropolitana Sud, Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Cornellà de Llobregat, España; Departament de Ciències Clíniques, Universitat de Barcelona (UB), Barcelona, España; Equip d'Atenció Primària Viladecans-2, Gerència d'Àmbit d'Atenció Primària Metropolitana Sud, Institut Català de la Salut, Gavà, Barcelona, España
| | - Casper D J den Heijer
- Department of Medical Microbiology, Maastricht University Medical Centre/CAPHRI, Maastricht, Países Bajos
| | - Bonaventura Bolíbar
- Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Barcelona, España; Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, España.
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Dhoubhadel BG, Yasunami M, Nguyen HAT, Suzuki M, Vu TH, Thi Thuy Nguyen A, Dang DA, Yoshida LM, Ariyoshi K. Bacterial load of pneumococcal serotypes correlates with their prevalence and multiple serotypes is associated with acute respiratory infections among children less than 5 years of age. PLoS One 2014; 9:e110777. [PMID: 25360707 PMCID: PMC4216008 DOI: 10.1371/journal.pone.0110777] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 09/18/2014] [Indexed: 12/03/2022] Open
Abstract
Background Among pneumococcal serotypes, some serotypes are more prevalent in the nasopharynx than others; determining factors for higher prevalence remain to be fully explored. As non-vaccine serotypes have emerged after the introduction of 7-valent conjugate vaccines, study of serotype specific epidemiology is in need. When two or more serotypes co-colonize, they evolve rapidly to defend host's immune responses; however, a clear association of co-colonization with a clinical outcome is lacking. Methods Children less than 5 years old who were admitted to hospital due to acute respiratory infections (ARI) (n = 595) and healthy children (n = 350) were recruited. Carriage of pneumococcus was determined by culture and lytA PCR in the nasopharyngeal samples. Serotype/serogroup detection and its quantification were done by the nanofluidic real time PCR system. Spearman's correlation and logistic regression were used to examine a correlation of serotype/serogroup specific bacterial load with its prevalence and an association of co-colonization with ARI respectively. Results Serotype/serogroup specific bacterial load was correlated with its prevalence, both in ARI cases (Spearman's rho = 0.44, n = 186; P<0.0001) and healthy children (Spearman's rho = 0.41, n = 115; P<0.0001). The prevalence of multiple serotypes was more common in ARI cases than in healthy children (18.5% vs 7.1%; aOR 2.92, 95% CI: 1.27–6.71; P = 0.01). The dominant serotype in the co-colonization had a 2 log10 higher bacterial load than the subdominant serotype, both in ARI cases (P<0.001) and healthy children (P<0.05). Conclusions High bacterial load in the nasopharynx may help transmit pneumococci among hosts, and increase the chance of successful acquisition and colonization. Co-colonization of multiple serotypes of pneumococci is linked with ARI, which infers the interactions of multiple serotypes may increase their pathogenicity; however, they may compete for growth in number.
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Affiliation(s)
- Bhim Gopal Dhoubhadel
- Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Michio Yasunami
- Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Hien Anh Thi Nguyen
- Department of Bacteriology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Motoi Suzuki
- Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Thu Huong Vu
- Department of Bacteriology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Ai Thi Thuy Nguyen
- Department of Microbiology, Khanh Hoa General Hospital, NhaTrang, Vietnam
| | - Duc Anh Dang
- Department of Bacteriology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Lay-Myint Yoshida
- Department of Pediatric Infectious Diseases, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
- * E-mail:
| | - Koya Ariyoshi
- Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
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Dagan R, Juergens C, Trammel J, Patterson S, Greenberg D, Givon-Lavi N, Porat N, Gurtman A, Gruber WC, Scott DA. Efficacy of 13-valent pneumococcal conjugate vaccine (PCV13) versus that of 7-valent PCV (PCV7) against nasopharyngeal colonization of antibiotic-nonsusceptible Streptococcus pneumoniae. J Infect Dis 2014; 211:1144-53. [PMID: 25355940 DOI: 10.1093/infdis/jiu576] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Pediatric respiratory infections caused by antibiotic-nonsusceptible Streptococcus pneumoniae (ANSP) continue to present an important challenge, even after introduction of 7-valent pneumococcal conjugate vaccine (PCV7). This randomized double-blind trial assessed the potential additional impact of PCV13 over PCV7 on reducing ANSP carriage. METHODS Healthy infants were randomly assigned to receive PCV13 (n = 932) or PCV7 (n = 934) at ages 2, 4, 6, or 12 months. Eight nasopharyngeal specimens were collected by swabbing between ages 2 and 24 months. S. pneumoniae isolates were serotyped and tested for antimicrobial susceptibility by the disk-diffusion method and the Etest. Nasopharyngeal acquisition and prevalence of ANSP during ages 7-24 months were compared between the 2 vaccine groups. RESULTS In general, new acquisition of pneumococci nonsusceptible to penicillin, erythromycin, clindamycin, penicillin plus erythromycin, and multiple drugs (≥3 antibiotics) was significantly lower in the PCV13 group compared with the PCV7 group; the main serotypes contributing to this significant decrease were serotype 19F, present in PCV13 and PCV7, and serotypes 6A and 19A, present in PCV13 only. CONCLUSIONS PCV13 has a significant added benefit over PCV7 in reducing carriage of ANSP. Because carriage determines transmission, these results suggest that PCV13 will provide protection against ANSP disease that exceeds protection provided by PCV7. CLINICAL TRIALS REGISTRATION NCT00508742.
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Affiliation(s)
- Ron Dagan
- Pediatric Infectious Disease Unit, Soroka University Medical Center Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | | | | | | | - David Greenberg
- Pediatric Infectious Disease Unit, Soroka University Medical Center Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Noga Givon-Lavi
- Pediatric Infectious Disease Unit, Soroka University Medical Center Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Nurith Porat
- Pediatric Infectious Disease Unit, Soroka University Medical Center Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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Characteristics of invasive pneumococcal disease in hospitalized children in Austria. Eur J Pediatr 2014; 173:469-76. [PMID: 24221605 DOI: 10.1007/s00431-013-2193-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Revised: 10/09/2013] [Accepted: 10/17/2013] [Indexed: 10/26/2022]
Abstract
UNLABELLED In a prospective surveillance study covering all pediatric wards in Austria, 308 cases of invasive pneumococcal disease (IPD) were reported in hospitalized children <5 years of age between 2002 and 2012. Incidence was 7.1 per 100,000 per year for IPD with a case fatality rate of 3 %, and 1.9 per 100,000 per year for pneumococcal meningitis with a case fatality rate of 9 %. At hospital discharge, 17 % of the children were not fully recovered and suffered from problems such as hearing or motor deficits. Persistent sequelae 6 months after hospital discharge were present in 13 % of the children, a finding that emphasizes the seriousness of IPD. From 2007 onwards, we observed a shift of pneumococcal serotypes from those covered by the heptavalent vaccine to serotypes consequently added to 10- and 13-valent vaccines, particularly regarding serotype 19A. Among antimicrobial resistances detected, macrolide resistance was predominant; however, between 2002 and 2012, we saw an overall decrease of resistance rates. CONCLUSION Considering this change of serotypes and the high rate of permanent sequelae after IPD, our data show the importance of pediatric pneumococcal vaccination and the relevance of continuous monitoring of circulating serotypes. By the end of 2012, which was the first year of universal mass vaccination against pneumococcal disease in Austria, no change in the incidence of invasive pneumococcal disease was observed yet.
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Chiu NC. Pneumococcal nasopharyngeal colonization. Pediatr Neonatol 2013; 54:289-90. [PMID: 23856426 DOI: 10.1016/j.pedneo.2013.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 06/13/2013] [Indexed: 11/24/2022] Open
Affiliation(s)
- Nan-Chang Chiu
- Department of Pediatrics, Mackay Memorial Hospital, 92, Chung-Shan North Road, Taipei, Taiwan.
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Dynamics of Streptococcus pneumoniae serotypes causing acute otitis media isolated from children with spontaneous middle-ear drainage over a 12-year period (1999-2010) in a region of northern Spain. PLoS One 2013; 8:e54333. [PMID: 23349853 PMCID: PMC3551958 DOI: 10.1371/journal.pone.0054333] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Accepted: 12/11/2012] [Indexed: 11/19/2022] Open
Abstract
The aim of this study was to determine the serotype and clonal distribution of pneumococci causing acute otitis media (AOM) and their relationship with recurrences and mixed infections with other microorganisms under the influence of the 7-valent pneumococcal conjugate vaccine (PCV7). To do this, all pneumococcal isolates collected from the spontaneous middle-ear drainage of children <5 years old diagnosed of AOM by their pediatrician or their general practitioner from 1999 to 2010 were phenotypically characterized and the most frequent serotypes were genotyped. In the 12-year study, 818 episodes of pneumococcal AOM were detected, mostly (70.5%) in children younger than 2 years old. In 262 episodes (32%), the pneumococci were isolated with another bacterium, mainly (n = 214) Haemophilus influenzae. Mixed infections were similar in children under or over 2 years old. The most frequent serotypes were 19A (n = 227, 27.8%), 3 (n = 92, 11.2%) and 19F (n = 74, 9%). Serotypes included in the PCV7 sharply decreased from 62.4% in the pre-vaccination (1999–2001) to 2.2% in the late post-vaccination period (2008–2010). Serotype diversity steadily increased after the introduction of the PCV7 but decreased from 2008–2010 due to the predominant role of serotype 19A isolates, mostly ST276 and ST320. The prevalence of serotype 3 doubled from 6.1% (20/326) in 1999–2004 to 14.6% (72/492) in 2005–2010. Relapses mainly occurred in male infants infected with isolates with diminished antimicrobial susceptibility. Reinfections caused by isolates with the same serotype but different genotype were frequent, highlighting the need for genetic studies to differentiate among similar strains. In conclusion, the main change in pneumococcal AOM observed after the introduction of the PCV7 was the sharp decrease in vaccine serotypes. Also notable was the high burden of serotype 19A in total pneumococcal AOM before and especially after the introduction of the PCV7, as well as in relapses and reinfections.
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Hernandez-Bou S, Garcia-Garcia JJ, Gene A, Esteva C, del Amo E, Muñoz-Almagro C. Pneumococcal carriage in children attending a hospital outpatient clinic in the era of pneumococcal conjugate vaccines in Barcelona. Diagn Microbiol Infect Dis 2012; 74:258-62. [DOI: 10.1016/j.diagmicrobio.2012.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 07/02/2012] [Accepted: 07/13/2012] [Indexed: 10/28/2022]
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Tenenbaum T, Franz A, Neuhausen N, Willems R, Brade J, Schweitzer-Krantz S, Adams O, Schroten H, Henrich B. Clinical characteristics of children with lower respiratory tract infections are dependent on the carriage of specific pathogens in the nasopharynx. Eur J Clin Microbiol Infect Dis 2012; 31:3173-82. [DOI: 10.1007/s10096-012-1682-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Accepted: 06/11/2012] [Indexed: 10/28/2022]
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