Serosurveillance for vaccine-preventable diseases: A look inside the pertussis experience / Serovigilancia de enfermedades prevenibles por vacunación: una mirada desde la experiencia con la tosferina

Abstract Introduction: Serological surveillance (serosurveillance) provides the most direct measure of herd immunity of vaccine-preventable diseases. Little is known about the opportunities and challenges of serosurveillance experiences, particularly pertussis. Objective: To describe the process of serosurveillance for vaccine-preventable diseases with an emphasis on the experience of pertussis in the metropolitan area of Antioquia (Valle de Aburrá) in 2015 and 2016 and analyze the contributions and challenges for its sustainability. Materials and methods: We described the planning and conduction of serosurveillance of pertussis antibodies of mothers and in the umbilical cord at the time of delivery in eight hospitals based on random sampling and their capacity to advance the serosurveillance periodically. We compared the contributions and the challenges of this experience with other probabilistic and non-probabilistic programs. Results: We achieved the participation of hospitals and mothers respecting the delivery care process. We established a serum bank following ethical and technical guidelines. This program based on the random selection of hospitals and mothers has enabled the estimation of antibodies prevalence in mothers and in the umbilical cord, which has been possible given the high coverage of hospital care during childbirth at a lower cost and fewer risks than a population-based survey in conflictive areas. The main challenges for the sustainability of this program are the creation of stable jobs and access to funding and legal and methodological long-term frameworks. Conclusions: Hospital serosurveillance as described is an option to monitor the impact of vaccination on the population. Our experience could be reproduced in other regions under similar conditions if the above-mentioned challenges are solved.

Resumen Introducción. La vigilancia serológica es la forma más directa de medir la inmunidad de rebaño frente a las enfermedades prevenibles por vacunación. Poco se sabe acerca de las oportunidades y los desafíos de las experiencias de serovigilancia, en general y, específicamente, la de la tosferina. Objetivo. Describir el proceso de serovigilancia de enfermedades prevenibles por vacunación con énfasis en la experiencia en el caso de la tosferina en el área metropolitana de Antioquia (Valle de Aburrá) en el 2015 y el 2016 y analizar lo que dicha experiencia ha aportado y los desafíos que persisten para su sostenibilidad. Materiales y métodos. Se describió el proceso de planeación y el desarrollo de la serovigilancia de tosferina en el momento del parto en ocho hospitales seleccionados al azar, así como la capacidad para adelantar el programa de manera periódica. Se compararon los aportes y los desafíos en el curso de esta experiencia con los de otros programas poblacionales probabilistas e institucionales no probabilistas. Resultados. Se logró la participación de los hospitales y de las madres con pleno respeto del proceso de atención del parto, y se conformó un banco de sueros siguiendo lineamientos éticos y técnicos. El programa permitió estimar la prevalencia de anticuerpos en la madre y en el cordón umbilical, lo que se facilitó por la alta cobertura de atención hospitalaria del parto, a un menor costo y menos riesgos que los programas poblacionales en zonas conflictivas. Los principales desafíos para la sostenibilidad del programa son la estabilidad laboral del personal de salud, así como normas y una financiación de largo plazo. Conclusiones. La serovigilancia hospitalaria es una opción para monitorizar el impacto poblacional de la vacunación. Esta experiencia se podría extender a otras regiones en condiciones similares si se resuelven los retos mencionados.

Seroprevalencia contra Bordetella pertussis en embarazadas vacunadas y no vacunadas y neonatos en un hospital universitario de la provincia de Buenos Aires / Seroprevalence of Bordetella pertussis among vaccinated and unvaccinated pregnant women and newborn infants in a university hospital of Buenos Aires

Introducción. La tos convulsa es una enfermedad altamente contagiosa causada por Bordetella pertussis. Tiene una alta tasa de morbilidad y mortalidad, especialmente, en los lactantes menores de seis meses de edad. En la Argentina, la incidencia y la mortalidad se han encontrado en aumento en las últimas 3 décadas. Objetivo. Determinar anticuerpos contra Bordetella pertussis en las mujeres embarazadas en el tercer trimestre de la gestación y en el recién nacido, medidos en la sangre del cordón. Métodos. Se disenó un estudio observacional, transversal. El estudio se inició en 2011 cuando la vacunación contra pertussis en la embarazada no estaba incluida en el Calendario Nacional de Vacunación y era opcional. Los anticuerpos se midieron en las madres en el tercer trimestre del embarazo y en la sangre del cordón umbilical al nacer. Las determinaciones de anticuerpos se realizaron con el kit de ELISA humano para IgG toxina pertussis ABCAMR. Se utilizó la prueba de chi² para comparar la prevalencia. Resultados. Se incluyó a 111 madres y a sus bebés, 35 hijos de madres no vacunadas (antes de la implementación de la vacuna en embarazadas) y 76 hijos de madres vacunadas. Los bebés de madres vacunadas presentaron anticuerpos IgG positivos en el 92% (70/76), mientras que los bebés de madres no vacunadas fueron negativos para anticuerpos IgG en el 100% (35/35) con una p < 0,001. Conclusión. En la población de vacunadas del estudio, se observó que sus hijos presentaron anticuerpos IgG positivos en el 92%. Este estudio apoya la necesidad de la inmunización materna contra Bordetella pertussis para proteger al recién nacido.

Introduction. Pertussis is a highly contagious disease caused by Bordetella pertussis. It poses a high morbidity and mortality rate, especially among infants younger than 6 months old. In Argentina, pertussis incidence and mortality have increased over the past three decades. Objective. To establish Bordetella pertussis antibody titers among pregnant women in their third trimester and among newborn infants, as measured in cord blood. Methods. This was an observational, crosssectional study. The study started in 2011; at that time, pertussis vaccination was not mandatory for pregnant women as per the national immunization schedule, only optional. Maternal antibodies were measured in the last trimester of pregnancy for women and in cord blood for newborn infants. Antibody titers were determined using Abcam's anti-Bordetella pertussis toxin (PT) IgG in vitro ELISA kit. The X2 test was used to compare prevalence rates. Results. The study included 111 mother-newborn infant dyads; 35 infants from unvaccinated mothers (before the introduction of the vaccine) and 76 from vaccinated mothers. Positive IgG antibodies were found in 92% (70/76) of infants born from vaccinated mothers whereas 100% (35/35) of infants born from unvaccinated mothers had negative results for antibodies; p < 0.001. Conclusion. In the vaccinated population of this study, 92% of infants had positive IgG antibodies. This study supports the need for maternal immunization against Bordetella pertussis to provide protection to newborn infants.

Vacunas anti-pertussis: acelular versus celular. ¿Acaso un regreso al pasado? / Pertussis vaccines: acellular versus whole cell. Perhaps a return to the past?

The resurgence of pertussis in the world and in our country has questioned the effectiveness of cellular and acellular vaccines. The reason why pertussis has not been controlled or eliminated after 70 years of implementation of the vaccination is probably multifactorial. This article, on the basis of questions and answers, describes the benefits and limitations of both cellular and acellular vaccines and suggests new strategies of vaccination in childhood. It is a fact that the currently applied vaccination does not eliminate the circulation of Bordetella pertussis in the community. Perhaps the introduction of vaccines with live B. pertussis, inhalation, will be able to eliminate the disease around the world.

El resurgimiento de la coqueluche en el mundo y en nuestro país ha puesto en tela de juicio la eficacia de las vacunas celulares y acelulares. Las razones de por qué la coqueluche no es controlada ni eliminada después de 70 años de implementación de la vacunación son diversas y probablemente multifactoriales. En este artículo, en base a preguntas y respuestas, se describen las bondades y limitaciones de tanto vacunas celulares como acelulares y queda sugerida una mejor forma de administrar ambas en la infancia. Es un hecho que la vacunación actualmente aplicada no elimina la circulación de Bordetella pertussis en la comunidad. Tal vez la introducción de vacunas con B. pertussis viva, inhalatoria, sea capaz de eliminar la enfermedad de la humanidad.

Pertussis may be the cause of prolonged cough in adolescents and adults in the interepidemic period

Objective: This study was aimed to evaluate the prevalence of pertussis in adolescents and adults with cough lasting more than 14 days and less than 30 days. Methods: This is a prospective observational study in interepidemic period of pertusis. Ten public health outpatient clinics in the city of Recife, Brazil, were randomly selected for the study. The study population consisted of individuals aged 10 years and over with cough that had lasted between 14 and 30 days. Nasopharyngeal swabs were collected for culture and PCR in order to identify Bordetella pertussis. We adopted the Centers for Disease Control and Prevention in the US (CDC) definition of cases of pertussis. Results: A total of 192 individuals were identified as suspected cases. Their mean age was 40.7 years. Pertussis was confirmed in 10 of the 192 suspected cases, with an estimated prevalence of 5.21% (95% confidence interval 2.03-8.38). All cases met the clinical case definition for pertussis; one suspect had both culture and PCR positive. PCR confirmed 100% of the cases, 7/10 by PCR and 3/10 by epidemiological linkage with a case confirmed by PCR. Conclusion: During an interepidemic period, 1 in 20 cases of prolonged cough had pertussis, suggesting this is an important cause of prolonged cough in adolescents and adults. .

Pertussis Prevalence in Korean Adolescents and Adults with Persistent Cough

We investigated the prevalence of pertussis in Korean adolescents and adults with persistent cough. Study population was adolescents (aged 11-20 yr) and adults (> or = 21 yr old) who showed persistent cough of 1-8 weeks' duration. Pertussis was diagnosed by culture, polymerase chain reaction (PCR), and serology. A total of 310 subjects participated in this study, and 76 cases (24.5%) met the criteria for laboratory-confirmed pertussis. The majority of the pertussis cases (66/76) were confirmed by serology, while 3 cases (1.0%) were diagnosed with culture, and 10 cases (3.2%) were detected with PCR. Of the 76 subjects diagnosed with pertussis, 20/86 cases were adolescents and 56/224 cases were adults. Neither adolescents nor adults received adolescent-adult booster against pertussis within the previous 5 yr. Pertussis can be a primary cause of persistent cough in Korean adolescents and adults.

Pertussis Seroprevalence in Korean Adolescents and Adults Using Anti-Pertussis Toxin Immunoglobulin G

This study was conducted to evaluate age-specific seroprevalence of pertussis in Korea and to formulate a strategy to prevent and reduce the incidence of pertussis. Residual serum samples of healthy adolescents and adults 11 yr of age or older were collected between July 2012 and December 2012, and anti-pertussis toxin (PT) IgG titers were measured using a commercial ELISA kit. We compared the mean anti-PT IgG titers and seroprevalence of pertussis of the six age groups: 11-20, 21-30, 31-40, 41-50, 51-60, and > or = 61 yr. A total of 1,192 subjects were enrolled. The mean anti-PT IgG titer and pertussis seroprevalence were 35.53 +/- 62.91 EU/mL and 41.4%, respectively. The mean anti-PT IgG titers and seroprevalence were not significantly different between the age groups. However, the seroprevalence in individuals 51 yr of age or older was significantly higher than in individuals younger than 51 yr (46.5% vs 39.1%, P = 0.017). Based on these results, a new pertussis prevention strategy is necessary for older adults.

Comparative analysis of the intracerebral mouse protection test and serological method for potency assays of pertussis component in DTP vaccine

The aim of this study was to compare the PSPT standardized in-house as an alternative to MPT for potency assays of pertussis component. Statistical analyses have showed similar pertussis potency values when PSPT was compared to MPT. Significant correlation between the potency results obtained by in vivo and in vitro assays was also been observed. Results by PSPT have demonstrated reproducibility and accuracy for potency pertussis control and this approach has been considered promising for use at least during the steps of production.

Consenso para el diagnóstico clínico y microbiológico y la prevención de la infección por Bordetella pertussis / Consensus on the clinical and microbiologic diagnosis of Bordetella pertussis, and infection prevention

La tos ferina sigue siendo responsable de una carga de enfermedad importante en el mundo. Aunque la implementación del uso de la vacuna contra esta enfermedad ha disminuido en gran medida el número de casos en la población pediátrica, se ha observado que la inmunidad inducida por la vacuna y por la infeccion natural disminuye con el tiempo lo que hace nuevamente susceptibles a adolescentes y adultos jóvenes que pueden transmitir la enfermedad a lactantes no inmunizados o con esquema de vacunación incompleto. Este documento, resultado de la reunión de un grupo internacional de expertos en la Ciudad de México, ha analizado la información médica reciente para establecer el estado actual de la epidemiología, diagnóstico, vigilancia y, especialmente, el valor de la dosis de refuerzo con dTpa en adolescentes y adultos como estrategia de prevención de tos ferina en México.

Pertussis continues to be responsible for a significant disease burden worldwide. Although immunization practices have reduced the occurrence of the disease among children, waning vaccine- and infection-induced immunity still allows the disease to affect adolescents and adults who, in turn, can transmit the disease to non-immunized or partially immunized infants. This document is the result of a meeting in Mexico City of international experts who analyzed recent medical information in order to establish the current status of the epidemiology, diagnosis and surveillance of pertussis and, especially, the value of the dTpa booster dose in adolescents and adults as a pertussis prevention strategy in Mexico.

Immunogenicity, reactogenicity and consistency of production of a Brazilian combined vaccine against diphtheria, tetanus, pertussis and Haemophilus influenzae type b

A randomized, double-blinded study evaluating the immunogenicity, safety and consistency of production of a combined diphtheria-tetanus-pertussis-Haemophilus influenzae type b vaccine entirely produced in Brazil by Bio-Manguinhos and Instituto Butantan (DTP/Hib-BM) was undertaken. The reference vaccine had the same DTP vaccine but the Hib component was produced using purified materials supplied by GlaxoSmithKline (DTP/Hib-GSK), which is registered and has supplied the Brazilian National Immunization Program for over more than five years. One thousand infants were recruited for the study and received vaccinations at two, four and six months of age. With respect to immunogenicity, the vaccination protocol was followed in 95.6 percent and 98.4 percent of infants in the DTP/Hib-BM and DTP/Hib-GSK groups, respectively. For the Hib component of the study, there was 100 percent seroprotection (>0.15 µg/mL) with all three lots of DTP/Hib-BM and DTP/Hib-GSK. The geometric mean titer (GMT) was 9.3 µg/mL, 10.3 µg/mL and 10.3 µg/mL for lots 1, 2 and 3 of DTP/Hib-BM, respectively, and the GMT was 11.3 g/mL for DTP/Hib-GSK. For diphtheria, tetanus and pertussis, seroprotection was 99.7 percent, 100 percent and 99.9 percent, respectively, for DTP/Hib-BM, three lots altogether and 99.2 percent, 100 percent and 100 percent for DTP/Hib-GSK. GMTs were similar across all lots and vaccines. Adverse events rates were comparable among the vaccine groups. The Brazilian DTP/Hib vaccine demonstrated an immunogenicity and reactogenicity profile similar to that of the reference vaccine.

Estado de portadores de bordetella pertussis en adolescentes de 12 a 19 años en el departamento del Tolima, Colombia, 2007 / A study into the carriers of bordetella pertussis between 12 and 19 years old Tolima, Colombia 2007

Antecedentes: se ha identificado Bordetella pertussis, en un porcentaje significativo en adolescentes y adultos, evidenciando su importancia como agente causante de hasta el 30 por ciento de los casos con este síndrome, que podrían jugar un papel importante en la transmisión de la enfermedad a niños lactantes.Objetivo:determinar el estado de portador de B. pertussis en adolescentes del Tolima y evaluar la técnica reacción en cadena de la polimerasa (PCR) como herramienta diagnóstica en el estado de portador.Materiales y métodos:estudio descriptivo de corte transversal; selección por muestreo aleatorio de 400 jóvenes de 12 a 19 años de edad.Recolección de muestrasnasofaríngeas, procesadas con técnicas de cultivo:inmunofluorescencia directa (IFD) con anticuerpos policlonales y reacción en cadena de la polimerasa (PCR) de la IS4801-IS4802, en el Instituto Nacional de Salud.Resultados:400 muestras procesadas con cultivo negativo; 34(8,5 por ciento) positivas para IFD y 132(33 por ciento) para PCR.Las dos técnicas fueron positivas 29(17 por ciento) y 263(66 por ciento) negativas para IFD y PCR.Proporción de los positivos del total de la muestra 34,25 por ciento (137/400).Sensibilidad de la PCR respecto a la IFD fue de 85,3 por ciento (IC:95 por ciento,68,2-94,5), especificidad de 71,9 por ciento (IC:95 por ciento, 66,9-76,3) VPP 22 por ciento(IC:95 por ciento, 15,4-30,2) y VPN 98,1 por ciento(IC:95 por ciento, 95,5-99,3).Conclusiones:se evidencia estado de portadores sanos en la población estudiada con diagnóstico por IFD y PCR; sin embargo, el cultivo bacteriano sigue siendo el “patrón de oro”, debido a esto, éste estudio no es concluyente. Es necesario evaluar continuamente el papel de los portadores de B. pertussis para establecer si existen portadores asintomáticos diagnosticados por cultivo...

Bordetella pertussis en estudiantes adolescentes de la Ciudad de México / Bordetella pertussis em estudantes adolescentes da Cidade do México / Bordetella pertussis in adolescents students in Mexico City

OBJETIVO: Estimar la seroprevalencia a Bordetella pertussis en escolares y sus contactos escolares y familiares. MÉTODOS: Un total de 12.273 estudiantes de 12 a 15 años de edad, de 14 escuelas secundarias públicas de la Ciudad de México fueron estudiados durante los meses de Septiembre 2002 a Marzo 2003. Se tomó muestra de exudado nasofaríngeo en adolescentes con tos de más de 14 días de evolución. La infección fue confirmada por la técnica de reacción en cadena de polimerasa. Se realizó estudio de contactos escolares y familiares. RESULTADOS: La incidencia de tos fue de 5 para 1.000 estudiantes. De los 61 estudiantes con tos incluidos en la muestra, 20 (32,8 por ciento) fueron positivos para Bordetella. De los 152 contactos escolares, 16 (10,6 por ciento) resultaron positivos, y ocho tenían tos. Uno de esos contactos fue el director de una de las escuelas responsable de más del 60 por ciento de los casos positivos (12/20), quien también dio lecciones a diez de los estudiantes infectados. De los 29 familiares, ocho (27,6 por ciento) fueron positivos, pertenecientes a tres familias. CONCLUSIONES: Los resultados muestran que la frecuencia de la enfermedad fue similar al comunicado en la población adolescente de otros países. Sin embargo, este trastorno no tiene necesariamente signos clínicos de la tos persistente y está sujeto a la existencia de infectados asintomáticos con Bordetella.

OBJECTIVE: To estimate seroprevalence of Bordetella pertussis in students and their community. METHODS: A total of 12,273 adolescent students aged 12 to 15 years from 14 public high schools in Mexico City were studied from September 2002 to March 2003. Nasopharyngeal samples were collected from those adolescents with whooping cough for more than 14 days. Infection was confirmed using polymerase chain reaction (PCR). All students, school staff and family exposed to PCR-confirmed cases were tested. RESULTS: Whooping cough rate was 5 to 1,000 students. Of those students (61) who were identified with whooping cough for more than 14 days, 20 (32.8 percent) were positive to Bordetella pertussis. Of 152 people exposed (contacts) to these cases, 16 (10.6 percent) were positive and only eight (50 percent) had whooping cough. One of these exposed (contacts) was the principal of a school that had more than 60 percent positive cases (12/20) and who was also a teacher of 10 infected students. Of 29 family members tested, eight (27.6 percent) were positive and from three different families. CONCLUSIONS: The study results show a similar rate of whooping cough in adolescents as seen in other countries. Since persistent cough is not always clinically seen in all infected individuals, there may be asymptomatic cases of Bordetella infection.

OBJETIVO: Estimar a soroprevalência a Bordetella pertussis em escolares e seus contatos. MÉTODOS: Foram examinados 12.273 alunos entre 12 e 15 anos de idade, de 14 escolas secundárias públicas da Cidade do México, de setembro de 2002 a março de 2003. Amostras de exudado nasofaríngeo foram coletadas de adolescentes com tosse por mais de 14 dias. A infecção foi confirmada por reação em cadeia da polimerase. Todos os alunos e funcionários dos colégios dos casos confirmados por reação em cadeia da polimerase e seus familiares foram testados. RESULTADOS: A incidência de tosse foi de 5 para 1.000 alunos. Dos 61 alunos com tosse amostrados, 20 (32,8 por cento) foram positivos para Bordetella. Dos 152 contatos desses alunos, 16 (10,6 por cento) foram positivos, dos quais oito apresentavam tosse. Um desses contatos foi a diretora de uma das escolas responsável por mais de 60 por cento dos casos positivos (12/20), que também deu aulas a dez desses alunos infectados. Dos 29 familiares testados, oito (27,6 por cento) foram positivos, pertencentes a três famílias. CONCLUSÕES: Os resultados mostram que a freqüência do agravo foi semelhante à reportada na população adolescente em outros países. Todavia, este agravo não tem necessariamente manifestações clínicas de tosse persistente, sendo possível a existência de sujeitos assintomáticos infectados com Bordetella.

Pertussis seroimmunity among mother-infant pairs and infant immune response to pertussis vaccination.

This study was designed to evaluate seroprevalence rates of antibodies to pertussis in mothers and their infants, and the immunogenicity of pertussis vaccine in the presence or absence of pertussis antibodies in infants. Blood samples were collected from 110 mother-infants pairs before the first dose of pertussis vaccination and from 69 infants 4-8 weeks after administration of the third dose of DTwP vaccine. Pertussis antibodies were >25 U/mL in 88(78.9%) mothers and 50(45.3%) infants with a mean titer of 67(SD 48.1) and 33.5 (34.7) U/mL, respectively. After administration of three doses of DTwP vaccine, 53(76.8%) infants were seroconverted (MCA titer 87.4 (51.3)U/mL. Immunologic response to vaccination was similar between the two groups of infants; 30/37 (81.1%) of seronegative infants and 23/32 (71.9%) of seropositive infants at pre-vaccination, showed seroconversion after the vaccination (P = 0.36). The results of this study demonstrated that most of the studied mothers were serologically immune to pertussis, and this immunity was transferred to their infants. Pre-vaccination antibody did not affect infants immune response to vaccination.

Monoclonal antibody that neutralizes pertussis toxin activities.

Pertussis or whooping cough is a disease with high mortality among infants and small children. The disease is caused by infection of the respiratory tract by a gram negative bacterium, Bordetella pertussis. The superficial colonized bacteria produce a myriad of toxins which enter the circulation causing various pathophysiologicalal changes in the host. Although antimicrobial therapy reduces the number of the coughed out bacteria and also the infectious time of the infected host, but it is not effective in amelioration of the clinical manifestations as the pertussis morbidity is due principally to the pertussis toxin (PT). Antibody based-therapy is frequently practiced in conjunction with other supportive measure to resuscitate the patient. Nevertheless, human derived antiserum against PT is of the limited supply and the ethical concern. Thus in this study a hybridoma clone, i.e. clone PT6-2G6, secreting monoclonal antibody (MAb) specific to the S1 subunit, the active enzyme of the PT that intracellularly ADP-ribosylates the host Gi-protein, was produced. The MAbPT6-2G6 inhibited the in vitro hemagglutination of chicken erythrocytes which is the activity of the B oligomer of PT; thus we hypothesize that the MAb bound to its epitope on the S1 subunit and stereologically hinders the binding sites of the B subunits. The MAb also inhibited ex vivo Chinese hamster ovarian cell clustering and neutralized the in vivo leucocytosis- promotion in mice which are usually mediated by intracellular S1 subunit. The large molecular nature of the intact MAb and its molecular hydrophilicity led us to speculate that the observed PT neutralizing activities of the MAb were due to interfering with the cellular entry of the S1 rather than the intracellular enzyme neutralizing activity per se. While further experiments are needed to pinpoint the MAb neutralizing activity and to identify the amino acid sequence and location of the MAbPT6-2G6 epitope, our findings indicate that this murine MAb, in its humanized-version, should have high therapeutic potential for pertussis.

Evaluation of respiratory model employing conventional NIH mice to access the immunity induced by cellular and acellular pertussis vaccines

The increasing number of pertussis cases reported on the last twenty years and the existence of new acellular vaccines reinforce the need of research for experimental models to assure the quality of available pertussis vaccines. In this study, allotments of whole-cell and acellular pertussis vaccines were tested through the Intranasal Challenge Model (INM) using conventional NIH mice. The results have been compared to those achieved by the "Gold standard" Intracerebral Challenge Model (ICM). In contrast to ICM, INM results did not show intralaboratorial variations. Statistical analysis by Anova and Ancova tests revealed that the INM presented reproducibility and allowed identification and separation of different products, including three-component and four-component accellular pertussis vaccines. INM revealed differences between pertussis vaccines. INM provides lower distress to the mice allowing the reduction of mice number including the possibility of using conventional mice (less expensive) under non-aseptic environment. Thus, INM may be used as an alternative method of verifying the consistence of allotment production, including acellular pertussis vaccines.

Vacuna anti-pertussis para uso en adolescentes y adultos / Pertussis vaccine for adolescents and adults

A pesar de la vacunación para prevenirla, la tos convulsiva es una enfermedad aún presente, afectando principalmente a la población de lactantes pequeños con alta morbi-mortalidad, pero también a los adolescentes y adultos que han perdido el efecto de la vacunación inicial; este segundo grupo se ha transformado en el principal reservorio y fuente de transmisión de Bordetella pertussis a lactantes. Las nuevas vacunas anti-pertussis, especialmente formuladas para este grupo etario, tienen un buen perfil de inmunogenicidad y de seguridad y su eficacia alcanza a 92%. La utilización universal de esta vacuna podría contribuir al control de la tos convulsiva en los grupos más susceptibles.

Vacina acelular contra pertússis para adolescentes / Acellular pertussis vaccine for adolescents

OBJETIVOS: A utilização da vacina de células inteiras contra coqueluche levou a uma redução significativa na incidência da enfermidade na criança. Essa mudança no perfil epidemiológico resultou em aumento no número de casos em adolescentes e adultos, conseqüente à perda da imunidade conferida pela doença ou por vacina após cerca de 10 anos, e em lactentes não imunizados ou incompletamente imunizados. O licenciamento da vacina tríplice bacteriana contra difteria, tétano e coqueluche acelular, com formulação específica para maiores de 10 anos de idade (dTpa), apontou para a possibilidade do controle da coqueluche na população das faixas etárias mais acometidas nos últimos anos. FONTE DE DADOS: As informações foram coletadas na base de dados MEDLINE. A pesquisa foi limitada ao período compreendido entre janeiro de 1995 a janeiro de 2006. SíNTESE DOS DADOS: Estão licenciadas em alguns países duas vacinas dTpa para a faixa etária maior de 10 anos de idade, uma delas contendo cinco componentes imunogênicos da Bordetella pertussis: toxina pertússis, hemaglutinina filamentosa, fimbrias 2 e 3 e pertactina, e a outra contendo três componentes: pertactina, hemaglutinina filamentosa e toxina pertússis inativada, sendo esta a única apresentação licenciada até o momento no Brasil. Embora a composição das duas vacinas seja diferente, os estudos mostram que a imunogenicidade e a eficácia são semelhantes. Entretanto, alguns autores enfatizam que existem dificuldades para a realização de uma avaliação mais precisa da resposta imunológica à vacina e sua duração. Vários países já recomendam de rotina o uso da vacina dTpa para adolescentes. O Canadá ampliou a população alvo até 54 anos de idade. A orientação é de que esse grupo receba uma dose da vacina como reforço do esquema básico de imunização. Isso é fundamentado em resultados de estudos que mostram que a duração da imunidade induzida pela vacina é em torno de 6 a 12 anos. As avaliações sobre o impacto econômico do uso rotineiro da vacina em adolescentes evidenciam uma relação custo-benefício positiva. Os resultados do impacto epidemiológico dependem da qualidade do diagnóstico para que os dados reflitam a realidade da doença. CONCLUSÕES: Embora existam algumas questões a serem esclarecidas, a literatura disponível sinaliza a possibilidade para a solução do .ressurgimento. da coqueluche com o uso da vacina dTpa.

Exanguineotransfusión como tratamiento para la coqueluche grave / Exchange transfusion for treatment of severe Pertussis

Introducción: La coqueluche grave en lactantes durante las primeras semanas de vida se asocia con una elevada mortalidad. Este mal pronóstico está relacionado a la presencia de hiperleucocitosis y al desarrollo de hipertensión pulmonar grave. El mecanismo de esta hipertensión pulmonar no está del todo aclarado, habiéndose reportado oclusión de la vasculatura pulmonar por trombos leucocitarios. En el último tiempo se han sugerido diversas terapias destinadas a la reducción de la masa leucocitaria, dentro de las cuales está la exanguineotransfusión. Casos clínicos: Reportamos dos lactantes menores de seis meses de edad con coqueluche grave, quienes cursaron con shock cardiogénico, hipoxemia e hipertensión pulmonar. Dentro de su estadía en UCI presentaron hiperleucocitosis, alcanzando inclusive niveles de leucocitosis extrema en uno de los pacientes (45-106 x 109/l), efectuándose exanguineotransfusión. Luego de esto hubo una significativa disminución del recuento leucocitario, asociado temporalmente a una mejoría progresiva en el estado cardiorrespiratorio, con sobrevida de los pacientes. Conclusión: En nuestra experiencia el curso clínico y pronóstico de estos pacientes fue distinto al habitualmente observado en los lactantes con coqueluche grave. En un futuro la exanguineotransfusión puede ser considerada como una terapia en los niños con coqueluche grave e hiperleucocitosis.

Vaccines: World Health Organization versus Federal Drug Administration recommended formula

Vaccines produced in accordance with WHO formulas, differ in concentration from those used in United States according to FDA formulas. We aimed to compare the immunogenicity of both formulas. Infants who were 6 weeks old were randomly put into 3 groups to receive 3 doses of vaccines at 6 weeks, 3 months and 5 months of age. The vaccines consisted of Haemophilus influenzae type b vaccine, diphtheria-tetanus-pertussis and oral polio vaccine. Antibody levels for polyribosylribitol phosphate [PRP], tetanus, diphtheria and poliovirus were measured 1 month after the third dose of vaccines. Although diphtheria and tetanus antigens in the FDA formula are half the concentration of the WHO formula, anti-tetanus and anti-diphtheria antibodies were significantly higher. No difference was found between groups regarding oral poliovirus vaccine

Isolation and purification of bordetella pertussis antigens

The amounts of pertussis toxin [PT] filamentus haemagglutinin [FHA], 69 KD outer memberane protein [69 KD O.M.P]. Agglutinogens [AGG] 2 and 3 and lipopolysacharid [L.P.S]. The antigens of bordetella pertussis by two physical and chemical extraction method appears from the Razi Institute cellular pertussis vaccine. These findings may have important implications for the evaluation of the protective substances and the immunogenicity of whole cell as opposed to acellular pertussis vaccines

The use of frozen inoculum and 0,2 por cento formaldehyde for inactivation of Pertussis vaccine production

The use of frozen seeds and the effect of the concentration of formaldehyde, and the removal of 2/3 of the supernatant were investigated in order to facilitate the production of pertussis cellular vaccine. Results indicated that is possible to replace fresh seeds by frozen ones, and the formaldehyde concentration can be increased to 0,2 por cento after the remotion of 2/3 of supernatant, resulting in a good vaccine preparation in a shorter time