The Experts below are selected from a list of 255 Experts worldwide ranked by ideXlab platform
Lode Schuerman - One of the best experts on this subject based on the ideXlab platform.
-
Reduced-antigen-content-Diphtheria-tetanus-acellular-pertussis and inactivated polio vaccine as a booster for adolescents 10 to 14 years of age
European Journal of Pediatrics, 2005Co-Authors: Rodrigo Vergara, Joanne Wolter, Miguel Tregnaghi, José Ussher, Sofía Navarro, Ricardo Rüttimann, Marcela Potin, Lode SchuermanAbstract:High rates of pertussis disease in adolescents suggest that additional boosting against pertussis would be beneficial. A combined acellular-pertussis-containing booster vaccine (dTpa-IPV; Boostrix™ Polio, n =440) was compared to separately administered dTpa (Boostrix™) and inactivated polio virus (IPV; Imovax Polio^®, n =219), and to DTPa-IPV (Infanrix™ IPV, n =111) vaccine in a partially blind, randomised controlled trial in 10–14 year olds. One month after vaccination, seroprotection/seropositivity rates for all antigens were similar for all groups. Although pertussis and Diphtheria Antibody geometric mean Antibody concentrations were higher after DTPa-IPV, all subjects had protective antibodies against Diphtheria, tetanus and polio, and at least 97% had a vaccine response to pertussis antigens. Reactogenicity of dTpa-IPV was comparable to dTpa + IPV, but dTpa-IPV was generally better tolerated than DTPa-IPV. Conclusion: The combined reduced-antigen-content-Diphtheria-tetanus-acellular-pertussis and IPV vaccine is immunogenic and well tolerated when administered to adolescents and could be used to improve the control of pertussis disease in this age group.
-
Anti-Diphtheria Antibody seroprotection rates are similar 10 years after vaccination with dTpa or DTPa using a mathematical model.
Vaccine, 2004Co-Authors: Brigitte Cheuvart, Margaret A. Burgess, Fred Zepp, Jussi Mertsola, Joanne Wolter, Lode SchuermanAbstract:Abstract The reduced antigen content Diphtheria, tetanus and pertussis (dTpa) vaccine (Boostrix™) has been shown to induce a strong booster response to all the vaccine components in 4–6 year olds. However, anti-Diphtheria Antibody levels were observed to be lower when compared to the “full strength” paediatric DTPa vaccine. To assess the impact of this difference on long-term protection, a mathematical model was developed to predict Diphtheria Antibody decay over time. The model was based on a linear decrease in log-transformed Antibody concentrations after the first year post-vaccination. When applied to data collected 3.5 years after vaccination of 4–6 year olds with either DTPa or dTpa, the model predicted that 10 years post-vaccination, 98.6% of subjects vaccinated with dTpa were likely to remain seroprotected against Diphtheria, compared to 99.6% vaccinated with DTPa. Therefore, the difference observed in Diphtheria Antibody geometric mean concentrations 1 month after booster vaccination at 4–6 years with dTpa or DTPa is unlikely to be of clinical relevance 10 years later at the time of the adolescent booster.
Hans L Bock - One of the best experts on this subject based on the ideXlab platform.
-
Booster vaccination of toddlers with reduced antigen content Diphtheria-tetanus-acellular pertussis vaccine.
Vaccine, 2009Co-Authors: Terry Nolan, Tilman A Ruff, Stephen B. Lambert, Jim Buttery, Kerry-ann F. O'grady, Catherine Streeton, Bernard Hoet, Hans L BockAbstract:Immunogenicity and reactogenicity of DTPa and reduced antigen dTpa booster vaccines were compared to a hepatitis A control vaccine in DTPa-primed toddlers aged 18-20 months. Post-booster, all DTPa and dTpa recipients were seroprotected against Diphtheria and tetanus, >93.3% had a booster response to pertussis. There were similar reactogenicity rates in the DTPa and dTpa vaccine recipients. Few Grade 3 symptoms were reported. Just over one in four children in the control group had Diphtheria Antibody at or potentially below the correlate of protection benchmark (0.016 IU/ml). Larger studies should evaluate potential benefits of reduced antigen vaccines and seroprotection in children who do not receive a booster dose of DTPa at this age, including protection against Diphtheria until subsequent booster doses are given. © 2009 Elsevier Ltd. All rights reserved.
-
assessment of nine candidate dtp vaccines with reduced amount of antigen and or without adjuvant as a fourth booster dose in the second year of life
Vaccine, 2006Co-Authors: Markus Knuf, Roland Sanger, Jorg Faber, Hans L Bock, Hugues Bogaerts, R Clemens, Peter Habermehl, Anne Schuind, Jean-baptist Du Prel, H. J. SchmittAbstract:Abstract Background The incidence of local reactions to Diphtheria-, tetanus and acellular pertussis (DTaP-) vaccines in infants and toddlers increases with each subsequent dose, and entire thigh swellings (ETS) have been reported. Lowering the amount of antigen or of adjuvant may decrease the reactogenicity of DTaP while maintaining a protective immune response. Objectives Following priming with three doses of a DTaP vaccine during infancy, the safety, reactogenicity and immunogenicity of nine different candidate DTaP-vaccines with reduced amounts of antigen and/or adjuvant given as fourth (booster) dose were evaluated. Methods Study participants were healthy infants aged 15–27 months at the time of booster vaccination. Each participant had received three doses of a DTaP vaccine (Infanrix™, GlaxoSmithKline, Rixensart, Belgium; “reference DTaP”) at age 3, 4, and 5 months as part of a previous clinical trial. More than 20,000 children were eligible for participation in the current study protocol at the time. In a first phase at a University hospital-based vaccination study center, nine sequential cohorts of 63–119 study subjects received one of nine different candidate vaccines. Patients and study personal were blinded with regard to which vaccine was currently in use. Reactogenicity was solicited from parents using diary cards. Blood was drawn prior to and 4 weeks after vaccination and immediately centrifuged. The serum was stored at −20 °C until serology was performed by ELISA tests. As soon as the first candidate vaccine with adequate reactogenicity and immunogenicity profile was identified in the first study phase, a second study phase was initiated in parallel, to evaluate the safety and reactogenicity of the respective candidate vaccine in private practices in large cohorts (1613–2095 study subjects per group). Results In the first study phase, DTaP with no aluminum induced the highest frequency of ETS and fever. All other candidate vaccines caused lower rates of local and general reactions than the reference DTaP. As a general rule, vaccines with less antigen induced fewer reactions, although there was no strict dose-response effect and the difference, e.g. between a one-tenth and a one-fifth DTaP dose (DTaP 1/5; DTaP 1/10) was not clinically relevant. Separate injections of Td and aP caused fewer general reactions than the respective TdaP combination and local reactions were higher at the aP than at the Td injection site. Again, as a general rule, reduced amounts of antigen induced lower Antibody concentrations, although all vaccines induced “protective” anti-tetanus and anti-Diphtheria Antibody responses. A total of 92–100% of children showed seroresponses to pertussis antigens even when vaccinated with reduced amounts of the respective pertussis antigen. Elimination of aluminum from DTaP vaccine induced higher anti-tetanus-Antibody concentrations and so did a reduction of the amount of Diphtheria antigen. Additional examples for antigen interaction were increased Antibody concentrations, observed with injection of Td and aP into different limbs. In the second study phase, all three vaccines evaluated (one with a reduced amount of Diphtheria antigen, TdaP; one with reduced amounts of all antigens, tdap; and one with a fifth dose of the reference vaccine (DTaP 1/5)) were safe and had an acceptable reactogenicity profile in a total of 4871 study subjects. Conclusions Local reactions due to DTaP booster doses in the second year of life can be reduced by reducing the amount of antigen in the respective vaccine while an adequate immunogenicity is maintained. Aluminum-free vaccines induced ETS and fever most commonly. Any changes in vaccine composition should lead to a full evaluation of the new product.
K T Goh - One of the best experts on this subject based on the ideXlab platform.
-
prevalence of Diphtheria and tetanus antibodies among adults in singapore a national serological study to identify most susceptible population groups
Journal of Public Health, 2016Co-Authors: L W Ang, Lyn James, K T GohAbstract:BACKGROUND In view of waning antitoxin titres over time after the last vaccine dose against Diphtheria and tetanus, we determined the immunity levels in adults to identify most susceptible groups for protection in Singapore. METHODS Our study involved residual sera from 3293 adults aged 18-79 who had participated in a national health survey in 2010. IgG Antibody levels were determined using commercial enzyme-linked immunosorbent assay. RESULTS Overall, 92.0% (95% confidence interval [CI]: 91.1-92.9%) had at least basic protection against Diphtheria (Antibody levels ≥0.01 IU/ml), while 71.4% (95% CI: 69.8-72.9%) had at least short-term protection against tetanus (Antibody levels >0.1 IU/ml). The seroprevalence declined significantly with age for both diseases; the drop was most marked in the 50- to 59-year age group for Diphtheria and 60- to 69-year age group for tetanus. There was a significant difference in seroprevalence by residency for Diphtheria (92.8% among Singapore citizens versus 87.1% among permanent residents; P = 0.001). The seroprevalence for tetanus was significantly higher among males (83.2%) than females (62.4%) (P < 0.0005). CONCLUSIONS It may be of value to consider additional vaccination efforts to protect older adults at higher risk for exposure against Diphtheria and tetanus, particularly those travelling to areas where Diphtheria is endemic or epidemic.
Joanne Wolter - One of the best experts on this subject based on the ideXlab platform.
-
Reduced-antigen-content-Diphtheria-tetanus-acellular-pertussis and inactivated polio vaccine as a booster for adolescents 10 to 14 years of age
European Journal of Pediatrics, 2005Co-Authors: Rodrigo Vergara, Joanne Wolter, Miguel Tregnaghi, José Ussher, Sofía Navarro, Ricardo Rüttimann, Marcela Potin, Lode SchuermanAbstract:High rates of pertussis disease in adolescents suggest that additional boosting against pertussis would be beneficial. A combined acellular-pertussis-containing booster vaccine (dTpa-IPV; Boostrix™ Polio, n =440) was compared to separately administered dTpa (Boostrix™) and inactivated polio virus (IPV; Imovax Polio^®, n =219), and to DTPa-IPV (Infanrix™ IPV, n =111) vaccine in a partially blind, randomised controlled trial in 10–14 year olds. One month after vaccination, seroprotection/seropositivity rates for all antigens were similar for all groups. Although pertussis and Diphtheria Antibody geometric mean Antibody concentrations were higher after DTPa-IPV, all subjects had protective antibodies against Diphtheria, tetanus and polio, and at least 97% had a vaccine response to pertussis antigens. Reactogenicity of dTpa-IPV was comparable to dTpa + IPV, but dTpa-IPV was generally better tolerated than DTPa-IPV. Conclusion: The combined reduced-antigen-content-Diphtheria-tetanus-acellular-pertussis and IPV vaccine is immunogenic and well tolerated when administered to adolescents and could be used to improve the control of pertussis disease in this age group.
-
Anti-Diphtheria Antibody seroprotection rates are similar 10 years after vaccination with dTpa or DTPa using a mathematical model.
Vaccine, 2004Co-Authors: Brigitte Cheuvart, Margaret A. Burgess, Fred Zepp, Jussi Mertsola, Joanne Wolter, Lode SchuermanAbstract:Abstract The reduced antigen content Diphtheria, tetanus and pertussis (dTpa) vaccine (Boostrix™) has been shown to induce a strong booster response to all the vaccine components in 4–6 year olds. However, anti-Diphtheria Antibody levels were observed to be lower when compared to the “full strength” paediatric DTPa vaccine. To assess the impact of this difference on long-term protection, a mathematical model was developed to predict Diphtheria Antibody decay over time. The model was based on a linear decrease in log-transformed Antibody concentrations after the first year post-vaccination. When applied to data collected 3.5 years after vaccination of 4–6 year olds with either DTPa or dTpa, the model predicted that 10 years post-vaccination, 98.6% of subjects vaccinated with dTpa were likely to remain seroprotected against Diphtheria, compared to 99.6% vaccinated with DTPa. Therefore, the difference observed in Diphtheria Antibody geometric mean concentrations 1 month after booster vaccination at 4–6 years with dTpa or DTPa is unlikely to be of clinical relevance 10 years later at the time of the adolescent booster.
Lyn James - One of the best experts on this subject based on the ideXlab platform.
-
prevalence of Diphtheria and tetanus antibodies among adults in singapore a national serological study to identify most susceptible population groups
Journal of Public Health, 2016Co-Authors: L W Ang, Lyn James, K T GohAbstract:BACKGROUND In view of waning antitoxin titres over time after the last vaccine dose against Diphtheria and tetanus, we determined the immunity levels in adults to identify most susceptible groups for protection in Singapore. METHODS Our study involved residual sera from 3293 adults aged 18-79 who had participated in a national health survey in 2010. IgG Antibody levels were determined using commercial enzyme-linked immunosorbent assay. RESULTS Overall, 92.0% (95% confidence interval [CI]: 91.1-92.9%) had at least basic protection against Diphtheria (Antibody levels ≥0.01 IU/ml), while 71.4% (95% CI: 69.8-72.9%) had at least short-term protection against tetanus (Antibody levels >0.1 IU/ml). The seroprevalence declined significantly with age for both diseases; the drop was most marked in the 50- to 59-year age group for Diphtheria and 60- to 69-year age group for tetanus. There was a significant difference in seroprevalence by residency for Diphtheria (92.8% among Singapore citizens versus 87.1% among permanent residents; P = 0.001). The seroprevalence for tetanus was significantly higher among males (83.2%) than females (62.4%) (P < 0.0005). CONCLUSIONS It may be of value to consider additional vaccination efforts to protect older adults at higher risk for exposure against Diphtheria and tetanus, particularly those travelling to areas where Diphtheria is endemic or epidemic.
-
Prevalence of Diphtheria and tetanus antibodies among adults in Singapore: a national serological study to identify most susceptible population groups
Journal of Public Health, 2015Co-Authors: Lyn JamesAbstract:Background In view of waning antitoxin titres over time after the last vaccine dose against Diphtheria and tetanus, we determined the immunity levels in adults to identify most susceptible groups for protection in Singapore. Methods Our study involved residual sera from 3293 adults aged 18–79 who had participated in a national health survey in 2010. IgG Antibody levels were determined using commercial enzyme-linked immunosorbent assay. Results Overall, 92.0% (95% confidence interval [CI]: 91.1–92.9%) had at least basic protection against Diphtheria (Antibody levels 0.01 IU/ml), while 71.4% (95% CI: 69.8–72.9%) had at least short-term protection against tetanus (Antibody levels .0.1 IU/ml). The seroprevalence declined significantly with age for both diseases; the drop was most marked in the 50- to 59-year age group for Diphtheria and 60- to 69-year age group for tetanus. There was a significant difference in seroprevalence by residency for Diphtheria (92.8% among Singapore citizens versus 87.1% among permanent residents; P ¼ 0.001). The seroprevalence for tetanus was significantly higher among males (83.2%) than females (62.4%) (P , 0.0005).