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Carl E. Frasch - One of the best experts on this subject based on the ideXlab platform.
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Technical Development of a New Meningococcal Conjugate Vaccine.
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2015Co-Authors: Carl E. Frasch, Subhash V Kapre, Che-hung Lee, Jean-marie PréaudAbstract:Group A Neisseria meningitidis has been a major cause of bacterial meningitis in the sub-Saharan region of Africa in the meningitis belt. Neisseria meningitidis is an encapsulated pathogen, and antibodies against the capsular polysaccharide are protective. Polysaccharide-protein Conjugate Vaccines have proven to be highly effective against several different encapsulated bacterial pathogens. Purified polysaccharide Vaccines have been used to control group A meningococcal (MenA) epidemics with minimal success. A monovalent MenA polysaccharide-tetanus toxoid Conjugate was therefore developed. This Vaccine was developed by scientists working with the Meningitis Vaccine Project, a partnership between PATH and the World Health Organization. A high-efficiency conjugation method was developed in the Laboratory of Bacterial Polysaccharides in the Center for Biologics Evaluation and Research and transferred to the Serum Institute of India, Ltd, which then developed methods for purification of the group A polysaccharide and used its tetanus toxoid as the carrier protein to produce the now-licensed, highly effective MenAfriVac Conjugate Vaccine. Although many years of application of meningococcal polysaccharide Vaccines have had minimal success in preventing meningococcal epidemics in the meningitis belt of Africa, our collaborative efforts to develop a MenA Conjugate Vaccine yielded a safe and highly effective Vaccine. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.
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Technical Development of a New Meningococcal Conjugate Vaccine.
Clinical Infectious Diseases, 2015Co-Authors: Carl E. Frasch, Subhash V Kapre, Che-hung Lee, Jean-marie PréaudAbstract:Background. Group A Neisseria meningitidis has been a major cause of bacterial meningitis in the sub-Saharan region of Africa in the meningitis belt. Neisseria meningitidis is an encapsulated pathogen, and antibodies against the capsular polysaccharide are protective. Polysaccharide–protein Conjugate Vaccines have proven to be highly effective against several different encapsulated bacterial pathogens. Purified polysaccharide Vaccines have been used to control group A meningococcal (MenA) epidemics with minimal success. Methods. A monovalent MenA polysaccharide–tetanus toxoid Conjugate was therefore developed. This Vaccine was developed by scientists working with the Meningitis Vaccine Project, a partnership between PATH and the World Health Organization. Results. A high-efficiency conjugation method was developed in the Laboratory of Bacterial Polysaccharides in the Center for Biologics Evaluation and Research and transferred to the Serum Institute of India, Ltd, which then developed methods for purification of the group A polysaccharide and used its tetanus toxoid as the carrier protein to produce the now-licensed, highly effective MenAfriVac Conjugate Vaccine. Conclusions. Although many years of application of meningococcal polysaccharide Vaccines have had minimal success in preventing meningococcal epidemics in the meningitis belt of Africa, our collaborative efforts to develop a MenA Conjugate Vaccine yielded a safe and highly effective Vaccine.
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Development of a group A meningococcal Conjugate Vaccine, MenAfriVacTM
Human vaccines & immunotherapeutics, 2012Co-Authors: Carl E. Frasch, Marie-pierre Preziosi, F. Marc LaforceAbstract:Group A meningococcal disease has been an important public health problem in sub-Saharan Africa for over a century. Outbreaks occur there annually, and large epidemics occur at intervals ranging between 8 and 12 y. The Meningitis Vaccine Project was established in 2001 with funding from the Gates Foundation with the goal of developing, testing, licensing, and introducing an affordable group A meningococcal Conjugate Vaccine into Africa. From 2003 to 2009 a monovalent group A Conjugate Vaccine, MenAfriVacTM, was developed at the Serum Institute of India, Ltd through an innovative public/private partnership. Preclinical studies of the new Conjugate Vaccine were completed in 2004 and a Phase 1 study began in India in 2005. Phase 2/3 studies in African 1–29 y olds were completed in 2009 showing the new meningococcal A Conjugate Vaccine to be as safe as currently licensed meningococcal polysaccharide Vaccines, but much more immunogenic. After Indian market authorization (December 2009) and WHO prequalification...
Juhani Eskola - One of the best experts on this subject based on the ideXlab platform.
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streptococcus pneumoniae capsular polysaccharide diphtheria toxoid Conjugate Vaccine is immunogenic in early infancy and able to induce immunologic memory
Pediatric Infectious Disease Journal, 1998Co-Authors: Heidi Ahman, Helena Kayhty, Hannele Lehtonen, Odile Leroy, James Froeschle, Juhani EskolaAbstract:Background. Pneumococcal polysaccharide Vaccines are not protective against the most common pneumococcal infections in infancy. The importance of pneumococcal diseases and emerging antimicrobial resistance emphasize the need for prophylaxis. Methods. Pneumococcal Conjugate Vaccine, containing capsular polysaccharides from serotypes 6B, 14, 19F and 23F Conjugated to diphtheria toxoid (PncD), was given to 75 infants at 2, 4 and 6 months of age. Three dosages (1, 3 or 10 μg of each) were used. A placebo group of 49 infants received physiologic saline. Children were given a booster dose of either polysaccharide or Conjugate Vaccine at 14 months of age; the placebo group received Conjugate Vaccine. Antibody concentrations were determined with an enzyme immunoassay. Results. The highest dose induced the strongest response after primary immunization, but booster response was greatest in the group primed with the lowest dose. Polysaccharide and Conjugate Vaccines induced booster responses of the same magnitude. At 24 and 36 months of age the antibody concentrations were similar in children who had received the PncD in infancy and in children immunized at 14 months of age only. Conclusions. The PncD Conjugate Vaccine is immunogenic and able to induce immunologic memory.
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reduction of oropharyngeal carriage of haemophilus influenzae type b rib in children immunized with an rib Conjugate Vaccine
The Journal of Infectious Diseases, 1991Co-Authors: Aino K Takala, Helena Kayhty, Juhani Eskola, Maija Leinonen, Antti Nissinen, Eeva Pekkanen, Helena P MakelaAbstract:The oropharyngeal carriage of Haemophilus influenzae type b (Hib) was studied among 725 healthy 3-year-old children who had or had not been immunized with an Hib Conjugate Vaccine. Oropharyngeal swabs were collected during the childrens' well-child visit to their local child health center. Fourteen (3.5%) of the 398 unvaccinated children were oropharyngeal carriers of Hib, whereas none of the 327 children who had received Hib Conjugate Vaccine carried Hib (P less than .001). Carriage rates of non-type b H. influenzae (19%) or Streptococcus pneumoniae (18%) were the same irrespective of the Hib vaccination status of the children. Thus Hib Conjugate Vaccine, unlike Hib polysaccharide Vaccine, seems to be able to prevent oropharyngeal colonization by Hib.
Helena Kayhty - One of the best experts on this subject based on the ideXlab platform.
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Tolerability and immunogenicity of an 11-valent pneumococcal Conjugate Vaccine in adults.
Vaccine, 2001Co-Authors: T Wuorimaa, Helena Kayhty, O Leroy, J EskolaAbstract:We studied the safety and immunogenicity in healthy adults of an 11-valent pneumococcal Conjugate Vaccine. Capsular polysaccharides (PS) of serotypes 1, 4, 5, 7F, 9V, 19F and 23F were Conjugated to tetanus toxoid, and of serotypes 3, 6B, 14 and 18C to diphtheria toxoid. Ten subjects received the Conjugate Vaccine with and the other ten subjects without aluminium hydroxide adjuvant. The reference Vaccine was a marketed 23-valent PS Vaccine. Safety data were recorded over 5 days after the immunisation. IgG antibody concentrations, avidity and subclass distribution were measured by EIA. The Conjugate without aluminium induced more local adverse effects than the Conjugate with aluminium or PS Vaccine. All Vaccines evoked significant antibody increases to all Vaccine specific antigens. Both Conjugate Vaccines induced antibodies mainly of IgG(2) subclass, and adjuvanted Conjugate Vaccine induced IgG antibodies with increased avidity. This first administration, to man, of a mixed protein carrier 11-valent pneumococcal Conjugate Vaccine demonstrated its ability to induce an immune response without significant adverse effects, enabling further study on its use in paediatric populations.
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streptococcus pneumoniae capsular polysaccharide diphtheria toxoid Conjugate Vaccine is immunogenic in early infancy and able to induce immunologic memory
Pediatric Infectious Disease Journal, 1998Co-Authors: Heidi Ahman, Helena Kayhty, Hannele Lehtonen, Odile Leroy, James Froeschle, Juhani EskolaAbstract:Background. Pneumococcal polysaccharide Vaccines are not protective against the most common pneumococcal infections in infancy. The importance of pneumococcal diseases and emerging antimicrobial resistance emphasize the need for prophylaxis. Methods. Pneumococcal Conjugate Vaccine, containing capsular polysaccharides from serotypes 6B, 14, 19F and 23F Conjugated to diphtheria toxoid (PncD), was given to 75 infants at 2, 4 and 6 months of age. Three dosages (1, 3 or 10 μg of each) were used. A placebo group of 49 infants received physiologic saline. Children were given a booster dose of either polysaccharide or Conjugate Vaccine at 14 months of age; the placebo group received Conjugate Vaccine. Antibody concentrations were determined with an enzyme immunoassay. Results. The highest dose induced the strongest response after primary immunization, but booster response was greatest in the group primed with the lowest dose. Polysaccharide and Conjugate Vaccines induced booster responses of the same magnitude. At 24 and 36 months of age the antibody concentrations were similar in children who had received the PncD in infancy and in children immunized at 14 months of age only. Conclusions. The PncD Conjugate Vaccine is immunogenic and able to induce immunologic memory.
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reduction of oropharyngeal carriage of haemophilus influenzae type b rib in children immunized with an rib Conjugate Vaccine
The Journal of Infectious Diseases, 1991Co-Authors: Aino K Takala, Helena Kayhty, Juhani Eskola, Maija Leinonen, Antti Nissinen, Eeva Pekkanen, Helena P MakelaAbstract:The oropharyngeal carriage of Haemophilus influenzae type b (Hib) was studied among 725 healthy 3-year-old children who had or had not been immunized with an Hib Conjugate Vaccine. Oropharyngeal swabs were collected during the childrens' well-child visit to their local child health center. Fourteen (3.5%) of the 398 unvaccinated children were oropharyngeal carriers of Hib, whereas none of the 327 children who had received Hib Conjugate Vaccine carried Hib (P less than .001). Carriage rates of non-type b H. influenzae (19%) or Streptococcus pneumoniae (18%) were the same irrespective of the Hib vaccination status of the children. Thus Hib Conjugate Vaccine, unlike Hib polysaccharide Vaccine, seems to be able to prevent oropharyngeal colonization by Hib.
Jean-marie Préaud - One of the best experts on this subject based on the ideXlab platform.
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Technical Development of a New Meningococcal Conjugate Vaccine.
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2015Co-Authors: Carl E. Frasch, Subhash V Kapre, Che-hung Lee, Jean-marie PréaudAbstract:Group A Neisseria meningitidis has been a major cause of bacterial meningitis in the sub-Saharan region of Africa in the meningitis belt. Neisseria meningitidis is an encapsulated pathogen, and antibodies against the capsular polysaccharide are protective. Polysaccharide-protein Conjugate Vaccines have proven to be highly effective against several different encapsulated bacterial pathogens. Purified polysaccharide Vaccines have been used to control group A meningococcal (MenA) epidemics with minimal success. A monovalent MenA polysaccharide-tetanus toxoid Conjugate was therefore developed. This Vaccine was developed by scientists working with the Meningitis Vaccine Project, a partnership between PATH and the World Health Organization. A high-efficiency conjugation method was developed in the Laboratory of Bacterial Polysaccharides in the Center for Biologics Evaluation and Research and transferred to the Serum Institute of India, Ltd, which then developed methods for purification of the group A polysaccharide and used its tetanus toxoid as the carrier protein to produce the now-licensed, highly effective MenAfriVac Conjugate Vaccine. Although many years of application of meningococcal polysaccharide Vaccines have had minimal success in preventing meningococcal epidemics in the meningitis belt of Africa, our collaborative efforts to develop a MenA Conjugate Vaccine yielded a safe and highly effective Vaccine. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.
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Technical Development of a New Meningococcal Conjugate Vaccine.
Clinical Infectious Diseases, 2015Co-Authors: Carl E. Frasch, Subhash V Kapre, Che-hung Lee, Jean-marie PréaudAbstract:Background. Group A Neisseria meningitidis has been a major cause of bacterial meningitis in the sub-Saharan region of Africa in the meningitis belt. Neisseria meningitidis is an encapsulated pathogen, and antibodies against the capsular polysaccharide are protective. Polysaccharide–protein Conjugate Vaccines have proven to be highly effective against several different encapsulated bacterial pathogens. Purified polysaccharide Vaccines have been used to control group A meningococcal (MenA) epidemics with minimal success. Methods. A monovalent MenA polysaccharide–tetanus toxoid Conjugate was therefore developed. This Vaccine was developed by scientists working with the Meningitis Vaccine Project, a partnership between PATH and the World Health Organization. Results. A high-efficiency conjugation method was developed in the Laboratory of Bacterial Polysaccharides in the Center for Biologics Evaluation and Research and transferred to the Serum Institute of India, Ltd, which then developed methods for purification of the group A polysaccharide and used its tetanus toxoid as the carrier protein to produce the now-licensed, highly effective MenAfriVac Conjugate Vaccine. Conclusions. Although many years of application of meningococcal polysaccharide Vaccines have had minimal success in preventing meningococcal epidemics in the meningitis belt of Africa, our collaborative efforts to develop a MenA Conjugate Vaccine yielded a safe and highly effective Vaccine.
Katherine A. Poehling - One of the best experts on this subject based on the ideXlab platform.
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Potential Impact of Accelerating the Primary Dose of Pneumococcal Conjugate Vaccine in Infants
Archives of pediatrics & adolescent medicine, 2009Co-Authors: Jennifer M. Stancil, Timothy R. Peters, Laurence B. Givner, Katherine A. PoehlingAbstract:Objective To estimate the potential effect of the acceleration of administration of the first dose of pneumococcal Conjugate Vaccine from 2 months to 6 weeks of age. Design Prediction model using data from a retrospective cohort study. Setting Published data from 8 states that participated in Active Bacterial Core Surveillance of the Emerging Infections Program Network for pneumococcus before pneumococcal Conjugate Vaccine introduction (July 1, 1997- June 30, 2000). Participants A total of 759 739 live births under surveillance. Intervention Estimating the potential benefit of administration of the first dose of the pneumococcal Conjugate Vaccine at 6 weeks of age instead of 2 months of age. Main Outcome Measures Estimation of reduction in the rate of invasive pneumococcal disease in infants 61 to 90 days of age. Results The estimated direct effect of the acceleration of administration of the first dose of pneumococcal Conjugate Vaccine from 2 months to 6 weeks of age when this Vaccine was first introduced could have reduced the burden of invasive pneumococcal disease in infants 61 to 90 days of age by 39.9%, 56.0%, and 72.1% for respective Vaccine efficacies of 50%, 70%, and 90%. This translates into preventing an estimated 73, 103, and 133 cases of invasive pneumococcal disease per year among approximately 4 112 052 live births in the United States. Conclusions The acceleration of administration of the pneumococcal Conjugate Vaccine from 2 months to 6 weeks of age could reduce the burden of invasive pneumococcal disease among infants. This observation may be important when a new Conjugate Vaccine becomes available, particularly among populations with prevalent invasive pneumococcal disease from a serotype included in the new Vaccine.
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National impact of universal childhood immunization with pneumococcal Conjugate Vaccine on outpatient medical care visits in the United States
Pediatrics, 2006Co-Authors: Carlos G Grijalva, J. Pekka Nuorti, Katherine A. Poehling, Yuwei Zhu, Stacey W. Martin, Kathryn M. Edwards, Marie R GriffinAbstract:BACKGROUND. Since introduction of the heptavalent pneumococcal Conjugate Vaccine in the United States in 2000, rates of invasive pneumococcal disease have declined. However, the national impact of heptavalent pneumococcal Conjugate Vaccine on pneumonia and otitis media remains unknown. OBJECTIVES. We compared national rates of outpatient visits for pneumonia and otitis media in children before and after heptavalent pneumococcal Conjugate Vaccine introduction. METHODS. Rates of ambulatory visits for pneumococcal and nonspecific pneumonia, otitis media, and other acute respiratory infections were compared before (1994–1999) and after (2002–2003) heptavalent pneumococcal Conjugate Vaccine introduction using the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey. To evaluate Vaccine effects while accounting for temporal variability, ratios of pneumococcal-related disease rates in children RESULTS. After the introduction of heptavalent pneumococcal Conjugate Vaccine, otitis media visit rates declined by 20% in children aged CONCLUSIONS. After heptavalent pneumococcal Conjugate Vaccine introduction, national rates of otitis media visits declined significantly in children
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national impact of universal childhood immunization with pneumococcal Conjugate Vaccine on outpatient medical care visits in the united states
Pediatrics, 2006Co-Authors: Carlos G Grijalva, Katherine A. Poehling, Stacey W. Martin, Kathryn M. Edwards, Pekka J Nuorti, Marie R GriffinAbstract:BACKGROUND: Since introduction of the heptavalent pneumococcal Conjugate Vaccine in the United States in 2000, rates of invasive pneumococcal disease have declined. However, the national impact of heptavalent pneumococcal Conjugate Vaccine on pneumonia and otitis media remains unknown. OBJECTIVES: We compared national rates of outpatient visits for pneumonia and otitis media in children before and after heptavalent pneumococcal Conjugate Vaccine introduction. METHODS: Rates of ambulatory visits for pneumococcal and nonspecific pneumonia, otitis media, and other acute respiratory infections were compared before (1994-1999) and after (2002-2003) heptavalent pneumococcal Conjugate Vaccine introduction using the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey. To evaluate Vaccine effects while accounting for temporal variability, ratios of pneumococcal-related disease rates in children < 2 years old (Vaccine target population) and in children 3 to 6 years old (not routinely vaccinated) were evaluated using a Poisson regression analysis. For children < 2 years old, the differences between observed and expected rates were the estimated Vaccine effects. RESULTS: After the introduction of heptavalent pneumococcal Conjugate Vaccine, otitis media visit rates declined by 20% in children aged < 2 years. This decline represented 246 fewer otitis media visits per 1000 children aged < 2 years annually. There were no significant decreases in outpatient visit rates for pneumonia or other acute respiratory infections for children aged < 2 years. CONCLUSIONS: After heptavalent pneumococcal Conjugate Vaccine introduction, national rates of otitis media visits declined significantly in children < 2 years old. Persistence of this trend will produce a significant reduction of the otitis media burden and further enhance the cost-effectiveness of heptavalent pneumococcal Conjugate Vaccine.