ABSTRACT
Pertussis has resurged during the last two decades in different countries. In particular in the 2010-2013 period large outbreaks were detected in US, Australia, UK and The Netherlands with significant mortality in infants. The epidemiological situation of pertussis points out the need to develop new vaccines and in this regard we previously developed a new vaccine based on outer membrane vesicles (OMVs) which have been shown to be safe and to induce protection in mice. Here we have further investigated the properties of OMVs vaccines; in particular we studied the contribution of pertussis toxin (PTx) and pertactin (Prn) in OMVs-mediated protection against pertussis. PTx-deficient OMVs and Prn-deficient OMVs were obtained from defective Bordetella pertussis mutants. The absence of PTx or Prn did compromise the protective capacity of the OMVs formulated as Tdap vaccine. Whereas the protective efficacy of the PTx-deficient OMVs in mice was comparable to Prn-deficient OMVs, the protective capacity of both of them was significantly impaired when it was compared with the wild type OMVs. Interestingly, using OMVs obtained from a B. pertussis strain which does not express any of the virulence factors but expresses the avirulent phenotype; we observed that the protective ability of such OMVs was lower than that of OMVs obtained from virulent B. pertussis phase. However, it was surprising that although the protective capacity of avirulent OMVs was lower, they were still protective in the used mice model. These results allow us to hypothesize that OMVs from avirulent phase shares protective components with all OMVs assayed. Using an immune proteomic strategy we identified some common components that could play an important role in protection against pertussis.
Subject(s)
Bacterial Outer Membrane Proteins/immunology , Pertussis Toxin/immunology , Pertussis Vaccine/immunology , Virulence Factors, Bordetella/immunology , Whooping Cough/prevention & control , Animals , Antigens, Bacterial/immunology , Female , Mice, Inbred BALB CABSTRACT
Pertussis is a serious respiratory disease in infants that can also affect children and adults. Vaccination against pertussis was introduced in the 1950s and in the 1990s a resurgence of pertussis was observed worldwide. The aim of this work is to summarize the recent data concerning pertussis disease in different countries of Latin America. In this geographic region, pertussis is nationally notifiable and cases should be reported to the appropriate health department/Ministry. Though the surveillance systems are not the same among Latin America countries, over recent decades an increasing number of cases have been detected. Most of these cases correspond to patients younger than 6 months old who received fewer than three doses of vaccine. However, cases in adolescent and adults have also been detected. For this situation, which is not peculiar to Latin America countries, several explanations have been proposed.
Subject(s)
Pertussis Vaccine/therapeutic use , Whooping Cough/epidemiology , Epidemiological Monitoring , Humans , Immunity, Herd , Immunization, Secondary/methods , Incidence , Latin America/epidemiology , Pertussis Vaccine/administration & dosage , Whooping Cough/prevention & controlABSTRACT
Despite high vaccination coverage rates, pertussis continues to be a global concern, with increased incidence widely noted. The current pertussis epidemiologic situation has been mainly attributed to waning immunity and pathogen adaptation. To improve the disease control, a new generation of vaccines capable to overcome those weaknesses associated to the current vaccines need to be developed. Previously we have demonstrated that the outer membrane vesicles obtained from the recombinant Bordetella pertussis strain expressing PagL enzyme (OMVs(BpPagL)) are good vaccine candidates to protect against pertussis. In this work the OMVs(BpPagL) formulated with diphtheria and tetanus toxoids (Tdap(OMVsBpPagL)) was used to evaluate its capacity to offer protection against Argentinean clinical isolates and to induce long-term immunity. To these aims BALB/c mice were immunized with Tdap(OMVsBpPagL) and challenged with sublethal doses of the clinical isolate Bp106 selected as a representative circulating isolate. Comparisons with a current commercial Tdap vaccine used at a dose in which pertussis toxin level was equivalent to that of Tdap(OMVsBpPagL) were performed. With the normalized doses of both vaccines we observed that Tdap(OMVsBpPagL) protected against the clinical isolate infection, whereas current commercial Tdap vaccine showed little protection against such pathogen. Regarding long-term immunity we observed that the Tdap(OMVsBpPagL) protective capacity against the recommended WHO reference strain persisted at least 9 months. In agreement with these results Tdap(OMVsBpPagL) induced Th1 and Th2 immune response. In contrast, commercial Tdap induced Th2 but weak Th1 responses. All results presented here showed that Tdap(OMVsBpPagL) is an interesting formulation to be considered for the development of novel acellular multi-antigen vaccine.
Subject(s)
Bacterial Outer Membrane Proteins/immunology , Bordetella pertussis/classification , Cross Protection , Diphtheria-Tetanus-acellular Pertussis Vaccines/immunology , Whooping Cough/prevention & control , Animals , Antibodies, Bacterial/blood , Antibody Formation , Bordetella pertussis/genetics , Female , Genotype , Immunologic Memory , Mice , Mice, Inbred BALB C , Pertussis Toxin/immunology , Recombinant Proteins/immunology , Th1 Cells/immunology , Th2 Cells/immunology , Vaccines, Acellular/immunologyABSTRACT
El objetivo del trabajo consistió en diseñar y validar una PCR en formato convencional que permita confirmar la presencia o ausencia de Bordetella pertussis y detectar otras especies del género, como Bordetella parapertussis y Bordetella bronchiseptica, que pudieran estar involucradas en el cuadro clínico de coqueluche. A tal fin se diseñó una reacción en cadena de la polimerasa (PCR) múltiple que amplifica una secuencia del promotor del gen de Toxina Pertussis y otra del gen de la Toxina Adenilato Ciclasa-Hemolisina. Se validó la metodología siguiendo esquemas publicados anteriormente. Se optimizaron las condiciones de la PCR. Se validó la metodología obteniéndose un límite de detección para ambas secuencias de 0,5 bacterias por reacción. Se validó, además, la especificidad y robustez de la técnica. Se presenta una nueva herramienta diagnóstica optimizada y validada, que permite detectar la presencia de las especies de Bordetella más frecuentemente involucradas en el cuadro clínico de coqueluche. Su uso combinado con alguna de las PCR habituales en diagnóstico, como la PCR IS481, permite aumentar la sensibilidad del diagnóstico de esta en¡fermedad, la especificidad del mismo discriminando los resultados falsos positivos/negativos y aumentar el conocimiento sobre los agentes etiológicos implicados en esta patología.(AU)
The aim of the present work was to design and validate a conventional PCR that enables to confirm the presence or absence of Bordetella pertussis and to detect other Bordetella species, such as Bordetella parapertussis metoand B. bronchiseptica, that may be involved in this pathology. To this aim, a multiplex PCR that amplifies a sequence of the promoter of the Pertussis Toxin gene and a sequence of the Adenylate Cyclase Toxin-Hemolysin gene were designed. The PCR was validated following previously published schemes. PCR conditions were optimized. The methodology was validated obtaining a detection limit of 0.5 bacteria per reaction, for both sequences. Specificity and robustness of the technique were also validated. A new optimized and validated tool to detect the presence of the Bordetella species most frequently responsible of pertussis was presented. The combined use with some of the usual PCR, such as IS 481, may increase the sensitivity of the diagnosis of this disease, its specificity discriminating false positive/negative results and increase awareness of the etiologic agents involved in this pathology.(AU)
O objetivo do trabalho foi desenhar e validar uma reaþÒo em cadeia da polimerase (PCR) em formato convencional que permita confirmar a presenþa ou ausÛncia de Bordetella pertussis e detectar outras espécies do gÛnero, como Bordetella parapertussis e Bordetella bronchiseptica, que pudessem estar envolvidas no quadro clínico de coqueluche. Para tal, foi desenhada uma PCR múltipla que amplifica uma sequÛncia do promotor do gene de Toxina Pertussis e outra do gene da Toxina Adenilato Ciclase-Hemolisina. A metodologia foi validada seguindo esquemas publicados anteriormente. Foram otimizadas as condiþ§es da PCR. Validou-se a metodologia obtendo-se um limite de detecþÒo para ambas as sequÛncias de 0,5 bactérias por reaþÒo. Validou-se também a especificidade e robustez da técnica. Apresenta-se uma nova ferramenta diagnóstica otimizada e validada, que permite detectar a presenþa das espécies de Bordetella mais frequentemente envolvidas no quadro clínico de coqueluche. Seu uso combinado com alguma das PCR habituais em diagnóstico, como a PCR IS481, permite aumentar a sensibilidade do diagnóstico desta doenþa, a especificidade do mesmo discriminando os resultados falsos positivos/negativos e aumentar o conhecimento sobre os agentes etiológicos envolvidos nesta patologia.(AU)
ABSTRACT
El objetivo del trabajo consistió en diseñar y validar una PCR en formato convencional que permita confirmar la presencia o ausencia de Bordetella pertussis y detectar otras especies del género, como Bordetella parapertussis y Bordetella bronchiseptica, que pudieran estar involucradas en el cuadro clínico de coqueluche. A tal fin se diseñó una reacción en cadena de la polimerasa (PCR) múltiple que amplifica una secuencia del promotor del gen de Toxina Pertussis y otra del gen de la Toxina Adenilato Ciclasa-Hemolisina. Se validó la metodología siguiendo esquemas publicados anteriormente. Se optimizaron las condiciones de la PCR. Se validó la metodología obteniéndose un límite de detección para ambas secuencias de 0,5 bacterias por reacción. Se validó, además, la especificidad y robustez de la técnica. Se presenta una nueva herramienta diagnóstica optimizada y validada, que permite detectar la presencia de las especies de Bordetella más frecuentemente involucradas en el cuadro clínico de coqueluche. Su uso combinado con alguna de las PCR habituales en diagnóstico, como la PCR IS481, permite aumentar la sensibilidad del diagnóstico de esta enfermedad, la especificidad del mismo discriminando los resultados falsos positivos/negativos y aumentar el conocimiento sobre los agentes etiológicos implicados en esta patología.
The aim of the present work was to design and validate a conventional PCR that enables to confirm the presence or absence of Bordetella pertussis and to detect other Bordetella species, such as Bordetella parapertussis metoand B. bronchiseptica, that may be involved in this pathology. To this aim, a multiplex PCR that amplifies a sequence of the promoter of the Pertussis Toxin gene and a sequence of the Adenylate Cyclase Toxin-Hemolysin gene were designed. The PCR was validated following previously published schemes. PCR conditions were optimized. The methodology was validated obtaining a detection limit of 0.5 bacteria per reaction, for both sequences. Specificity and robustness of the technique were also validated. A new optimized and validated tool to detect the presence of the Bordetella species most frequently responsible of pertussis was presented. The combined use with some of the usual PCR, such as IS 481, may increase the sensitivity of the diagnosis of this disease, its specificity discriminating false positive/negative results and increase awareness of the etiologic agents involved in this pathology.
O objetivo do trabalho foi desenhar e validar uma reação em cadeia da polimerase (PCR) em formato convencional que permita confirmar a presença ou ausência de Bordetella pertussis e detectar outras espécies do gênero, como Bordetella parapertussis e Bordetella bronchiseptica, que pudessem estar envolvidas no quadro clínico de coqueluche. Para tal, foi desenhada uma PCR múltipla que amplifica uma sequência do promotor do gene de Toxina Pertussis e outra do gene da Toxina Adenilato Ciclase-Hemolisina. A metodologia foi validada seguindo esquemas publicados anteriormente. Foram otimizadas as condições da PCR. Validou-se a metodologia obtendo-se um limite de detecção para ambas as sequências de 0,5 bactérias por reação. Validou-se também a especificidade e robustez da técnica. Apresenta-se uma nova ferramenta diagnóstica otimizada e validada, que permite detectar a presença das espécies de Bordetella mais frequentemente envolvidas no quadro clínico de coqueluche. Seu uso combinado com alguma das PCR habituais em diagnóstico, como a PCR IS481, permite aumentar a sensibilidade do diagnóstico desta doença, a especificidade do mesmo discriminando os resultados falsos positivos/negativos e aumentar o conhecimento sobre os agentes etiológicos envolvidos nesta patologia.
Subject(s)
Bordetella , Bordetella Infections/diagnosis , Multiplex Polymerase Chain Reaction/methods , Bordetella bronchiseptica , Bordetella parapertussis , Bordetella pertussisABSTRACT
INTRODUCCION: Pertussis es una enfermedad inmunoprevenible respiratoria que afecta a la población infantil y a los adolescentes/adultos. Para diseñar estrategias que mejoren el control de la enfermedad, resulta esencial profundizar el conocimiento de su epidemiología.OBJETIVO: Estimar la frecuencia de casos de pertussis en 5 provincias argentinas, analizar la implicancia de las características socio-sanitarias de la población e identificar la fuente más probable de contagio.METODOS: Se realizó un trabajo multidisciplinario y multicéntrico empleando algoritmos consensuados. Se estudió a niños menores de 1 año (caso índice, CI) y sus contactos. Para los análisis, se incorporó la información obtenida durante el período a una base de datos ya existente.RESULTADOS: Durante 2006-2011 se analizaron 18.106 muestras de pacientes con sintomatología compatible con pertussis, y se confirmaron 3.766 casos. La mayor proporción de casos confirmados y de casos fatales (8 a 21 por año) se registró en los menores de 1 año. Un análisis de la epidemiología de 113 grupos familiares, constituidos por al menos un CI y dos contactos, determinó que en más del 50% el caso primario no se correspondió al CI. Análisis preliminares mostraron a los convivientes adultos jóvenes como posible fuente de infección de la población vulnerable. En relación con la implicancia de la situación socio-sanitaria en la epidemiología de pertussis, la evolución de los síntomas y la distribución por edades de los casos confirmados mostraron una desigualdad entre los barrios carecientes y los no carecientes.CONCLUSIONES: Se detectó la presencia de más de un caso de pertussis en los grupos familiares. Los adultos jóvenes convivientes serían los responsables de transmitir la infección a los más pequeños. Por la influencia de las condiciones socio-sanitarias en la epidemiología de pertussis, se detectaron patrones diferenciales en la distribución de casos.
INTRODUCTION: Pertussis is an immune preventable resporatory disease affecting the pediatric population and teens/adults. To design better strategies for the disease control, it is essential to improve epidemiological knowledge.OBJECTIVE: To estimate the frequency of pertussis cases in 5 Argentine provinces, to analyze the implication of the socio-economic characteristics and to identify the most likely source of infection.METHODS: A multidisciplinary, multicenter study was conducted, using consensus algorithms. The analysis was focused on children under 1 year (index cases, IC) and their contacts. The information obtained was incorporated into a previous database.RESULTS: 18.106 samples of patients with symptoms compatible with pertussis were analyzed during 2006-2011. Of these cases, 3.766 were confirmed in the lab. The largest proportion of confirmed cases and fatal cases (8-21 per year) were registered in children under 1 year. An epidemiologic analysis of 113 family units, consisting in at least one IC and two contacts, found that in over 50% the primary case did not correspond to the IC. A preliminary analysis showed that the young and adult cohabitants were the possible source of infection for vulnerable populations. Regarding the implications of the socio-sanitary conditions in the disease epidemiology, the evolution of symptoms and the age group distribution of confirmed cases were unequeal between poor and non-poor neighborhoods.CONCLUSIONS: The study detected the presence of more than one case of pertussis in family units. Young and adult cohabitants would be responsible for transmitting the infection to children. Due to the influence of socio-sanitary conditions in the epidemiology of pertussis, differential patterns were detected in the distribution of cases.
Subject(s)
Infant , Social Class , Infant , Sanitary Profiles , Whooping Cough , Whooping Cough/epidemiology , Argentina , Public HealthABSTRACT
INTRODUCCION: Pertussis es una enfermedad inmunoprevenible respiratoria que afecta a la población infantil y a los adolescentes/adultos. Para diseñar estrategias que mejoren el control de la enfermedad, resulta esencial profundizar el conocimiento de su epidemiología.OBJETIVO: Estimar la frecuencia de casos de pertussis en 5 provincias argentinas, analizar la implicancia de las características socio-sanitarias de la población e identificar la fuente más probable de contagio.METODOS: Se realizó un trabajo multidisciplinario y multicéntrico empleando algoritmos consensuados. Se estudió a niños menores de 1 año (caso índice, CI) y sus contactos. Para los análisis, se incorporó la información obtenida durante el período a una base de datos ya existente.RESULTADOS: Durante 2006-2011 se analizaron 18.106 muestras de pacientes con sintomatología compatible con pertussis, y se confirmaron 3.766 casos. La mayor proporción de casos confirmados y de casos fatales (8 a 21 por año) se registró en los menores de 1 año. Un análisis de la epidemiología de 113 grupos familiares, constituidos por al menos un CI y dos contactos, determinó que en más del 50% el caso primario no se correspondió al CI. Análisis preliminares mostraron a los convivientes adultos jóvenes como posible fuente de infección de la población vulnerable. En relación con la implicancia de la situación socio-sanitaria en la epidemiología de pertussis, la evolución de los síntomas y la distribución por edades de los casos confirmados mostraron una desigualdad entre los barrios carecientes y los no carecientes.CONCLUSIONES: Se detectó la presencia de más de un caso de pertussis en los grupos familiares. Los adultos jóvenes convivientes serían los responsables de transmitir la infección a los más pequeños. Por la influencia de las condiciones socio-sanitarias en la epidemiología de pertussis, se detectaron patrones diferenciales en la distribución de casos.
INTRODUCTION: Pertussis is an immune preventable resporatory disease affecting the pediatric population and teens/adults. To design better strategies for the disease control, it is essential to improve epidemiological knowledge.OBJECTIVE: To estimate the frequency of pertussis cases in 5 Argentine provinces, to analyze the implication of the socio-economic characteristics and to identify the most likely source of infection.METHODS: A multidisciplinary, multicenter study was conducted, using consensus algorithms. The analysis was focused on children under 1 year (index cases, IC) and their contacts. The information obtained was incorporated into a previous database.RESULTS: 18.106 samples of patients with symptoms compatible with pertussis were analyzed during 2006-2011. Of these cases, 3.766 were confirmed in the lab. The largest proportion of confirmed cases and fatal cases (8-21 per year) were registered in children under 1 year. An epidemiologic analysis of 113 family units, consisting in at least one IC and two contacts, found that in over 50% the primary case did not correspond to the IC. A preliminary analysis showed that the young and adult cohabitants were the possible source of infection for vulnerable populations. Regarding the implications of the socio-sanitary conditions in the disease epidemiology, the evolution of symptoms and the age group distribution of confirmed cases were unequeal between poor and non-poor neighborhoods.CONCLUSIONS: The study detected the presence of more than one case of pertussis in family units. Young and adult cohabitants would be responsible for transmitting the infection to children. Due to the influence of socio-sanitary conditions in the epidemiology of pertussis, differential patterns were detected in the distribution of cases.
Subject(s)
Infant , Whooping Cough , Whooping Cough/epidemiology , Infant , Sanitary Profiles , Social Class , Argentina , Public HealthABSTRACT
Los dirigentes...dijeron que ya no se va a luchar con armas ni flechas. Ahora se va a luchar con papel y lapiz, hacia un destino de grandeza y felicidad para el pueblo guarani, porque las nuevas generaciones que despiertan al protagonismo, necesitan retomar los ideales de independencia de nuestros abuelos para continuar la marcha, rescatando los aciertos y superando los errores, en la construccion de una patria nueva, asentada en la justicia, la verdad y la libertad de nuestro pueblo
