Acellular Vaccine

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T R Einarson - One of the best experts on this subject based on the ideXlab platform.

  • Economic impact of the introduction of an Acellular pertussis Vaccine in Canada: a 6-year analysis.
    Vaccine, 2009
    Co-Authors: M Iskedjian, T R Einarson, Gaston De Serres, John H. Walker
    Abstract:

    Abstract Background Between July 1997 and April 1998, Canadian public health agencies switched from the whole cell Vaccine to the Acellular Vaccine for pertussis immunization. The Acellular Vaccine provided better efficacy and fewer adverse events than the whole cell Vaccine did. Objective To determine the economic impact of replacing the whole cell Vaccine with an Acellular Vaccine in Canada. Methods A decision analytic model was developed comparing costs and outcomes of pertussis vaccination for Canadian children born in the years 1991–2004. Effectiveness was measured as number of avoided pertussis cases as well as the number of avoided hospital admissions. Incremental costs per avoided pertussis case and per avoided hospital admission were calculated for Ministry of Health (MoH) and societal (SOC) perspectives. Various one-way sensitivity analyses as well as a Monte Carlo simulation were performed by varying key model parameters. Results The switch in immunization programs resulted in an incremental cost to the MoH of CAD $108 per pertussis case avoided (CAD $0.96 per child-year). From the SOC perspective, there was a savings of CAD $184 per pertussis case avoided (CAD $0.13 per child-year). The one-way sensitivity analyses provided incremental cost-effective ratios (ICERs) ranging from an incremental cost of CAD $1034 per avoided pertussis case from the MoH perspective to a saving of CAD $1583 per avoided case from the SOC perspective. The Monte Carlo simulation confirmed the robustness of these results. Conclusions Pertussis vaccination with AcE was cost-saving from the societal perspective and cost-effective from the Ministry of Health perspective.

  • Economic Evaluation of an Extended Acellular Pertussis Vaccine Program for Adolescents in Québec, Canada
    Pediatric Drugs, 2005
    Co-Authors: M Iskedjian, Gaston De Serres, John H. Walker, T R Einarson
    Abstract:

    Objective: Pertussis is a frequent cause of cough illness in adolescents. In Canada, immunization against pertussis in public programs has been restricted to children under 7 years of age. The purpose of this analysis was to estimate the health and economic impact of an additional booster dose of the Acellular Vaccine in adolescents in Québec. Method: We performed a cost-effectiveness analysis, based on a predictive spreadsheet dynamic model following a cohort of 90 929 adolescents in Québec from the age of 14 years over a 10-year period from the Québec Ministry of Health (MOH) and societal (SOC) perspectives. The model was used to compare costs (2003 values) and benefits of an adolescent vaccination program (AVP), including a diptheria, tetanus, and Acellular pertussis (dTacp) Vaccine administered at age 14 years, with current practice. Results: From the MOH perspective, a booster vaccination of dTacp at age 14 years via the AVP would produce a yearly additional expected cost of $Can1.06 per adolescent with an incremental cost-effectiveness ratio (ICER) of $Can480 per pertussis case avoided based on a 10-year period. When outcomes are discounted at 3%, the ICER rises to $Can527 per discounted pertussis case avoided. From the SOC perspective, the AVP would cost $Can0.83 per adolescent per year with an additional cost per avoided pertussis case of $Can377 ($Can414 per additional discounted case of pertussis avoided). Over the 10-year period, 2012 non-discounted cases of pertussis would be prevented with approximately two hospital admissions averted. Conclusion: This study suggests that administering a booster dose of dTacp at age 14 years to replace the diptheria and tetanus vaccination will slightly increase the economic burden from MOH and SOC perspectives; however, the number of pertussis cases and the number of hospital admissions will decrease.

  • Economic evaluation of an extended Acellular pertussis Vaccine program for adolescents in Québec, Canada.
    Paediatric drugs, 2005
    Co-Authors: M Iskedjian, Gaston De Serres, John H. Walker, T R Einarson
    Abstract:

    Objective: Pertussis is a frequent cause of cough illness in adolescents. In Canada, immunization against pertussis in public programs has been restricted to children under 7 years of age. The purpose of this analysis was to estimate the health and economic impact of an additional booster dose of the Acellular Vaccine in adolescents in Quebec.

  • Economic evaluation of a new Acellular Vaccine for pertussis in Canada.
    PharmacoEconomics, 2001
    Co-Authors: M Iskedjian, T R Einarson, B J O'brien, J G De Serres, R Gold, I M Gemmill, N Milkovich, A Rosner
    Abstract:

    Pertussis is a highly contagious infection affecting mainly children. Acellular pertussis Vaccines were recently introduced in Canada based on evidence of improved safety and efficacy over whole cell Vaccines, the current standard of care. The following study reports the economic impact of replacing the whole cell Vaccine (wP) by a new Acellular Vaccine (aP) in the Ontario pertussis immunisation programme. For a hypothetical cohort of 100,000 children from birth to the age of 8 years, the costs and consequences of pertussis vaccination with either aP or wP were compared. A decision analytical model was constructed for Vaccine delivery, treatment of pertussis cases and Vaccine adverse events, with analyses from the viewpoints of the Ontario Ministry of Health and society. The main outcomes were expected number of pertussis cases, hospitalisations, and workdays lost by parents. Data on Vaccine effectiveness, pertussis incidence, and other parameters used in the model were from published literature. Costs were discounted at 5%, and extensive sensitivity analyses were undertaken. Over 8 years, in a cohort of 100,000 children, the introduction of aP would prevent 10,500 cases of pertussis, avoiding 504 hospital admissions and 73,500 days of work absence. For Ontario, healthcare cost savings over the same period would amount to 275,585 Canadian dollars ($Can), and societal savings to $Can9,752,864

M Iskedjian - One of the best experts on this subject based on the ideXlab platform.

  • Economic impact of the introduction of an Acellular pertussis Vaccine in Canada: a 6-year analysis.
    Vaccine, 2009
    Co-Authors: M Iskedjian, T R Einarson, Gaston De Serres, John H. Walker
    Abstract:

    Abstract Background Between July 1997 and April 1998, Canadian public health agencies switched from the whole cell Vaccine to the Acellular Vaccine for pertussis immunization. The Acellular Vaccine provided better efficacy and fewer adverse events than the whole cell Vaccine did. Objective To determine the economic impact of replacing the whole cell Vaccine with an Acellular Vaccine in Canada. Methods A decision analytic model was developed comparing costs and outcomes of pertussis vaccination for Canadian children born in the years 1991–2004. Effectiveness was measured as number of avoided pertussis cases as well as the number of avoided hospital admissions. Incremental costs per avoided pertussis case and per avoided hospital admission were calculated for Ministry of Health (MoH) and societal (SOC) perspectives. Various one-way sensitivity analyses as well as a Monte Carlo simulation were performed by varying key model parameters. Results The switch in immunization programs resulted in an incremental cost to the MoH of CAD $108 per pertussis case avoided (CAD $0.96 per child-year). From the SOC perspective, there was a savings of CAD $184 per pertussis case avoided (CAD $0.13 per child-year). The one-way sensitivity analyses provided incremental cost-effective ratios (ICERs) ranging from an incremental cost of CAD $1034 per avoided pertussis case from the MoH perspective to a saving of CAD $1583 per avoided case from the SOC perspective. The Monte Carlo simulation confirmed the robustness of these results. Conclusions Pertussis vaccination with AcE was cost-saving from the societal perspective and cost-effective from the Ministry of Health perspective.

  • Economic Evaluation of an Extended Acellular Pertussis Vaccine Program for Adolescents in Québec, Canada
    Pediatric Drugs, 2005
    Co-Authors: M Iskedjian, Gaston De Serres, John H. Walker, T R Einarson
    Abstract:

    Objective: Pertussis is a frequent cause of cough illness in adolescents. In Canada, immunization against pertussis in public programs has been restricted to children under 7 years of age. The purpose of this analysis was to estimate the health and economic impact of an additional booster dose of the Acellular Vaccine in adolescents in Québec. Method: We performed a cost-effectiveness analysis, based on a predictive spreadsheet dynamic model following a cohort of 90 929 adolescents in Québec from the age of 14 years over a 10-year period from the Québec Ministry of Health (MOH) and societal (SOC) perspectives. The model was used to compare costs (2003 values) and benefits of an adolescent vaccination program (AVP), including a diptheria, tetanus, and Acellular pertussis (dTacp) Vaccine administered at age 14 years, with current practice. Results: From the MOH perspective, a booster vaccination of dTacp at age 14 years via the AVP would produce a yearly additional expected cost of $Can1.06 per adolescent with an incremental cost-effectiveness ratio (ICER) of $Can480 per pertussis case avoided based on a 10-year period. When outcomes are discounted at 3%, the ICER rises to $Can527 per discounted pertussis case avoided. From the SOC perspective, the AVP would cost $Can0.83 per adolescent per year with an additional cost per avoided pertussis case of $Can377 ($Can414 per additional discounted case of pertussis avoided). Over the 10-year period, 2012 non-discounted cases of pertussis would be prevented with approximately two hospital admissions averted. Conclusion: This study suggests that administering a booster dose of dTacp at age 14 years to replace the diptheria and tetanus vaccination will slightly increase the economic burden from MOH and SOC perspectives; however, the number of pertussis cases and the number of hospital admissions will decrease.

  • Economic evaluation of an extended Acellular pertussis Vaccine program for adolescents in Québec, Canada.
    Paediatric drugs, 2005
    Co-Authors: M Iskedjian, Gaston De Serres, John H. Walker, T R Einarson
    Abstract:

    Objective: Pertussis is a frequent cause of cough illness in adolescents. In Canada, immunization against pertussis in public programs has been restricted to children under 7 years of age. The purpose of this analysis was to estimate the health and economic impact of an additional booster dose of the Acellular Vaccine in adolescents in Quebec.

  • Economic evaluation of an extended Acellular pertussis Vaccine programme for adolescents in Ontario, Canada.
    Vaccine, 2004
    Co-Authors: M Iskedjian, John H. Walker, Michiel E. H. Hemels
    Abstract:

    Objective: Pertussis is a frequent cause of cough illness in adolescents. In Canada, immunization against pertussis in public programs has been restricted to children under 7 years of age. The purpose of this analysis was to estimate the health and economic impact of an additional booster dose of the Acellular Vaccine in adolescents in Quebec.

  • Economic evaluation of a new Acellular Vaccine for pertussis in Canada.
    PharmacoEconomics, 2001
    Co-Authors: M Iskedjian, T R Einarson, B J O'brien, J G De Serres, R Gold, I M Gemmill, N Milkovich, A Rosner
    Abstract:

    Pertussis is a highly contagious infection affecting mainly children. Acellular pertussis Vaccines were recently introduced in Canada based on evidence of improved safety and efficacy over whole cell Vaccines, the current standard of care. The following study reports the economic impact of replacing the whole cell Vaccine (wP) by a new Acellular Vaccine (aP) in the Ontario pertussis immunisation programme. For a hypothetical cohort of 100,000 children from birth to the age of 8 years, the costs and consequences of pertussis vaccination with either aP or wP were compared. A decision analytical model was constructed for Vaccine delivery, treatment of pertussis cases and Vaccine adverse events, with analyses from the viewpoints of the Ontario Ministry of Health and society. The main outcomes were expected number of pertussis cases, hospitalisations, and workdays lost by parents. Data on Vaccine effectiveness, pertussis incidence, and other parameters used in the model were from published literature. Costs were discounted at 5%, and extensive sensitivity analyses were undertaken. Over 8 years, in a cohort of 100,000 children, the introduction of aP would prevent 10,500 cases of pertussis, avoiding 504 hospital admissions and 73,500 days of work absence. For Ontario, healthcare cost savings over the same period would amount to 275,585 Canadian dollars ($Can), and societal savings to $Can9,752,864

Scott A. Halperin - One of the best experts on this subject based on the ideXlab platform.

  • nature evolution and appraisal of adverse events and antibody response associated with the fifth consecutive dose of a five component Acellular pertussis based combination Vaccine
    Vaccine, 2003
    Co-Authors: Scott A. Halperin, Luis Barreto, Elaine L Mills, Roland Guasparini, David W Scheifele, Garry Humphreys, Bruce Smith
    Abstract:

    Abstract We performed a randomized, controlled clinical trial to characterize the evolution of the adverse events associated with the fifth consecutive dose of an Acellular pertussis Vaccine, and to assess the level of discomfort associated with the injection and the attitude of parents concerning these events. A total of 505 children who had received either four doses of Acellular pertussis Vaccine or whole-cell pertussis Vaccine were given a fifth dose of one of the two Vaccines. Adverse events were monitored by parents and collected by telephone or home visit at 4, 8, 12, 24, 48 and 72 h, and 7 and 28 days after immunization. Rates of injection site redness ≥50 mm were similar in recipients of five doses of Acellular pertussis Vaccine (32.8%) or five doses of whole-cell pertussis Vaccine (43.3%). Injection site swelling, tenderness, and decreased arm movement were all more frequent in children who received five doses of whole-cell pertussis Vaccine. Antibody levels before or after immunization did not predict those children who had increased injection site reactions. The children rated the injection site reactions as significantly more severe after five consecutive doses of whole-cell Vaccine. Parent satisfaction was higher after the Acellular Vaccine. We conclude that a fifth consecutive dose of a whole-cell pertussis Vaccine is associated with high rates of tender redness and swelling at the injection site, in contrast to a fifth consecutive dose of an Acellular pertussis Vaccine which is associated with high rates of non-painful redness. However, parents will still need to be aware of the high rates of injection site reactions expected after a fifth dose of Acellular pertussis Vaccine.

  • adverse reactions and antibody response to four doses of Acellular or whole cell pertussis Vaccine combined with diphtheria and tetanus toxoids in the first 19 months of life
    Vaccine, 1996
    Co-Authors: Scott A. Halperin, Luis Barreto, Brian J Eastwood, B Friesen, Lorna Medd, William Meekison, Roland Guasparini
    Abstract:

    To assess the safety, immunogenicity, and lot consistency of a five-component Acellular pertussis Vaccine combined with diphtheria and tetanus toxoid (Connaught Laboratories Limited), we randomly allocated 432 infants to receive one of three lots of an Acellular pertussis Vaccine or a single lot of whole cell pertussis Vaccine. Infants were immunized at 2, 4 and 6 months of age and between 17 and 19 months of age. Local and systemic adverse reactions were reported significantly more frequently by recipients of the whole cell than Acellular Vaccine after each dose. The antibody response against pertussis toxin, filamentous hemagglutinin, and 69 kDa protein was of greater magnitude in Acellular pertussis Vaccine recipients than whole cell pertussis Vaccine recipients. Small differences were detected amongst the Vaccine lots tested. We conclude that the Acellular pertussis Vaccine is safe and immunogenic for the first four doses in children under 2 years of age.

  • Acellular pertussis Vaccine as a booster dose for seventeen- to nineteen-month-old children immunized with either whole cell or Acellular pertussis Vaccine at two, four and six months of age.
    The Pediatric infectious disease journal, 1995
    Co-Authors: Scott A. Halperin, Luis Barreto, Elaine L Mills, Carolyn Pim, Brian Eastwood
    Abstract:

    The safety and immunogenicity of two formulations of an Acellular pertussis Vaccine as a booster at 17 to 19 months of age were assessed in children immunized at 2, 4 and 6 months of age with Acellular or whole cell pertussis Vaccine. In Study I 86 children primed with a five-component Acellular Vaccine combined with diphtheria and tetanus toxoids or with a whole cell pertussis-diphtheria-tetanus Vaccine were boosted with the same Vaccine. Local reactions (64% vs. 93% ; relative risk, 0.7 ; 95% confidence interval, 0.5 to 0.9) and systemic reactions (68% vs. 97% ; relative risk, 0.7 ; 95% confidence interval, 0.5 to 0.9) were less common after the fourth dose of Acellular Vaccine than after the fourth dose of whole cell Vaccine. In Study II 96 children primed with either an Acellular or whole cell pertussis Vaccine were boosted with an Acellular Vaccine. Local adverse reactions after booster immunization with Acellular Vaccine were more common in children primed with Acellular Vaccine than those primed with whole cell Vaccine (68% vs. 33% ; relative risk, 2.1 ; 95% confidence interval, 1.3 to 3.3). Antibody response to pertussis toxin, filamentous hemagglutinin and fimbriae were higher before and 1 month after the booster dose in children primed with the Acellular Vaccine. We conclude that the Acellular pertussis Vaccine is safe and immunogenic when used for the booster dose in children primed with either whole cell or Acellular Vaccine but is associated with local reactions.

Daniela Flavia Hozbor - One of the best experts on this subject based on the ideXlab platform.

  • Outer membrane vesicles derived from Bordetella parapertussis as an Acellular Vaccine against Bordetella parapertussis and Bordetella pertussis infection
    Vaccine, 2013
    Co-Authors: Daniela Bottero, María Emilia Gaillard, Agustina Juliana Errea, Griselda Moreno, E. Zurita, L. Pianciola, Martin Rumbo, Daniela Flavia Hozbor
    Abstract:

    Abstract Bordetella parapertussis , a close related species of B. pertussis , can also cause the disease named pertussis or whooping cough. The number of cases caused by this related pathogen has risen sustained in the last years. The widely used cellular (wP) or Acellular (aP) pertussis Vaccines have little or no efficacy against B. parapertussis. In an effort to devise an effective Acellular Vaccine against B. parapertussis infection, outer membrane vesicles (OMVs) were obtained from B. parapertussis . Proteomic analysis of the resulting OMVs, designated OMVsBpp, evidenced the presence of several surface immunogens including pertactin. The characterized OMVsBpp were used in murine B. parapertussis intranasal challenge model to examine their protective capacity when administered by systemic route. Immunized BALB/c mice were challenged with sublethal doses of B. parapertussis . Significant differences between immunized animals and the negative control group were observed ( p B. parapertussis infection, whereas current commercial aP Vaccine showed little protection against such pathogen. More interestingly, protection induced by OMVsBpp against B. pertussis was comparable to our previously designed Vaccine consisting in OMVs derived from B. pertussis (OMVsBp). For these experiments we used as a positive control the current commercial aP Vaccine in high dose. As expected aP offered protection against B. pertussis in mice. Altogether the results presented here showed that the OMVs from B. parapertussis are an attractive Vaccine candidate to protect against whooping cough induced by B. parapertussis but also by B. pertussis .

  • outer membrane vesicles obtained from bordetella pertussis tohama expressing the lipid a deacylase pagl as a novel Acellular Vaccine candidate
    Vaccine, 2011
    Co-Authors: Cristian J A Asensio, Daniela Bottero, María Emilia Gaillard, Griselda Moreno, E. Zurita, Martin Rumbo, Peter Van Der Ley, Arno Van Der Ark, Daniela Flavia Hozbor
    Abstract:

    Abstract In an effort to devise a safer and effective pertussis acelullar Vaccine, outer membrane vesicles (OMVs) were engineered to decrease their endotoxicity. The pag L gene from Bordetella bronchiseptica , which encodes a lipid A 3-deacylase, was expressed in Bordetella pertussis strain Tohama I. The resulting OMVs, designated OMVs Bp PagL , contain tetra- instead of penta-acylated LOS, in addition to pertussis surface immunogens such as pertactin and pertussis toxin, as the wild type OMVs. The characterized pertussis OMVs Bp PagL were used in murine B. pertussis intranasal (i.n.) challenge model to examine their protective capacity when delivered by i.n. routes. Immunized BALB/c mice were challenged with sublethal doses of B. pertussis . Significant differences between immunized animals and the PBS treated group were observed ( p p Bp PagL and wild type OMVs. All OMV preparations tested were non toxic according to WHO criteria; however, OMVs Bp PagL displayed almost no weight loss at 3 days post administration, indicating less toxicity when compared with wild type OMVs. Induction of IL6- and IL1-expression in lung after i.n. delivery as well as neutrophil recruitment to airways showed coincident results, with a lower induction of the proinflammatory cytokines and lower recruitment in the case of OMVs Bp PagL compared to wild type OMVs. Given their lower endotoxic activity and retained protective capacity in the mouse model, OMVs Bp PagL obtained from B. pertussis seem as interesting candidates to be considered for the development of novel multi-antigen Vaccine.

  • outer membrane vesicles as Acellular Vaccine against pertussis
    Vaccine, 2008
    Co-Authors: Roy Roberts, Daniela Bottero, María Emilia Gaillard, Griselda Moreno, Martin Rumbo, Matías Fingermann, Augusto Graieb, Daniela Flavia Hozbor
    Abstract:

    In this study the development and evaluation of outer membrane vesicles (OMVs) obtained from Bordetella pertussis as Vaccines against pertussis disease is described. SDS-PAGE, immunoblot techniques and gel electrophoresis associated to tandem mass spectrometry were used to describe the composition of the OMVs obtained from B. pertussis Tohama CIP 8132 strain. These techniques revealed the presence of the main well-known pertussis surface immunogens in the OMVs such as pertactin, adenylate cyclase—haemolysin, pertussis toxin, as well as the lipo-oligosaccharide (LOS). A total of 43 proteins were identified by mass spectrometry. Some of them were predicted to have outer membrane or periplasmic location and the others with cytoplasmic or unknown location. The characterized pertussis OMVs were used in murine B. pertussis intranasal (i.n.) challenge model to examine their protective capacity when delivered by different routes. Killed detoxified whole-cell B. pertussis bacteria were used as reference. For intraperitoneal (i.p.) immunization, aluminum hydroxide was used as adjuvant. Since i.n. treatment with OMVs as well as killed whole-cell bacteria enhanced markers of innate immune response such as TNFα, IL-6 and CCL20, i.n. immunizations were performed with no adjuvant added. Immunized BALB/c mice were intranasally challenged with sublethal doses of B. pertussis. Significant differences between immunized animals and the PBS treated group were observed (p < 0.001). Adequate elimination rates (p < 0.005) were observed in mice immunized either with OMV or whole-cell bacteria. Comparable results were obtained with both types of immunization route. In view to their capacity to induce airways innate and protective immunity in the mouse model, OMVs obtained from B pertussis are candidates to be used to protect against pertussis.

  • Outer membrane vesicles as Acellular Vaccine against pertussis.
    Vaccine, 2008
    Co-Authors: Roy Roberts, Daniela Bottero, María Emilia Gaillard, Griselda Moreno, Martin Rumbo, Matías Fingermann, Augusto Graieb, Daniela Flavia Hozbor
    Abstract:

    In this study the development and evaluation of outer membrane vesicles (OMVs) obtained from Bordetella pertussis as Vaccines against pertussis disease is described. SDS-PAGE, immunoblot techniques and gel electrophoresis associated to tandem mass spectrometry were used to describe the composition of the OMVs obtained from B. pertussis Tohama CIP 8132 strain. These techniques revealed the presence of the main well-known pertussis surface immunogens in the OMVs such as pertactin, adenylate cyclase-haemolysin, pertussis toxin, as well as the lipo-oligosaccharide (LOS). A total of 43 proteins were identified by mass spectrometry. Some of them were predicted to have outer membrane or periplasmic location and the others with cytoplasmic or unknown location. The characterized pertussis OMVs were used in murine B. pertussis intranasal (i.n.) challenge model to examine their protective capacity when delivered by different routes. Killed detoxified whole-cell B. pertussis bacteria were used as reference. For intraperitoneal (i.p.) immunization, aluminum hydroxide was used as adjuvant. Since i.n. treatment with OMVs as well as killed whole-cell bacteria enhanced markers of innate immune response such as TNFalpha, IL-6 and CCL20, i.n. immunizations were performed with no adjuvant added. Immunized BALB/c mice were intranasally challenged with sublethal doses of B. pertussis. Significant differences between immunized animals and the PBS treated group were observed (p

C. Locht - One of the best experts on this subject based on the ideXlab platform.

  • Pertussis: Where did we go wrong and what can we do about it?
    The Journal of infection, 2016
    Co-Authors: C. Locht
    Abstract:

    Pertussis or whooping cough, mainly caused by the Gram-negative coccobacillus Bordetella pertussis, is a severe respiratory disease that can by life-threatening especially in young infants. It has recently made a spectacular come-back in high vaccination-coverage countries, such as the US, Australia and many European countries. Although a trend towards increased pertussis incidence was already visible before the switch from whole-cell to Acellular Vaccines, it was really since the introduction of the Acellular Vaccines that the number of cases reached record highs. Several hypotheses have been proposed to explain these observations. Unexpectedly fast waning of Acellular Vaccine-induced protection may be one of the major reasons. Furthermore, evidence from a recent non-human primate model suggests that Acellular Vaccines, although protective against pertussis disease, do not protect against B. pertussis infection, which may explain many of the current observations on the resurgence of pertussis. Optimized use of current Vaccines has been explored, including cocoon vaccination of persons in close contact with newborn infants, neonatal vaccination and maternal immunization during pregnancy. All have their inherent limitations. New Vaccines are therefore desperately needed, and current efforts have been geared towards the identification of novel antigens and adjuvants to prolong immunity and ameliorate protection. The most advanced Vaccine candidate is live attenuated nasal BPZE1, a genetically modified B. pertussis derivative that has recently completed a first-in-man phase I trial and was shown to be safe in young male volunteers, able to transiently colonize the naso-pharynx and to induce antibody responses to B. pertussis antigens. This Vaccine candidate is designed to protect against both pertussis disease and B. pertussis infection and may therefore be useful for long-term control of pertussis.

  • Live pertussis Vaccines: will they protect against carriage and spread of pertussis?
    Clinical Microbiology and Infection, 2016
    Co-Authors: C. Locht
    Abstract:

    Pertussis is a severe respiratory disease that can be fatal in young infants. Its main aetiological agent is the Gram-negative micro-organism Bordetella pertussis. Vaccines against the disease have been in use since the 1950s, and global vaccination coverage has now reached more than 85%. Nevertheless, the disease has not been controlled in any country, and has even made a spectacular come-back in the industrialized world, where the first-generation whole-cell Vaccines have been replaced by the more recent, less reactogenic, Acellular Vaccines. Several hypotheses have been proposed to explain these observations, including the fast waning of Acellular Vaccine-induced protection. However, recent mathematical modelling studies have indicated that asymptomatic transmission of B. pertussis may be the main reason for the current resurgence of pertussis. Recent studies in non-human primates have shown that neither whole-cell, nor Acellular Vaccines prevent infection and transmission of B. pertussis, in contrast to prior exposure. New Vaccines that can be applied nasally to mimic natural infection without causing disease may therefore be useful for long-term control of pertussis. Several Vaccine candidates have been proposed, the most advanced of which is the genetically attenuated B. pertussis strain BPZE1. This Vaccine candidate has successfully completed a first-in-man phase I trial and was shown to be safe in young male volunteers, able to transiently colonize the nasopharynx and to induce antibody responses to B. pertussis antigens in all colonized individuals. Whether BPZE1 will indeed be useful to ultimately control pertussis obviously needs to be assessed by carefully conducted human efficacy trials.