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Hanna Nohynek

Publications and source records attributed to Hanna Nohynek.

At least 19 recordsLinked to original sources
PubMed2006

Response and persistence of antibodies to PRP-T and DTwP vaccines with concomitant administration of conjugate vaccines.

We first studied the immunogenicity of PRP-T and DTwP vaccines in Filipino infants given at 6, 10 and 14 weeks concomitantly with either an aluminum adjuvanted eleven-valent pneumococcal conjugate vaccine (11PncTD) or a meningococcal diphtheria-conjugated vaccine as compared to a control group that received only DTwP/PRP-T. The GMCs and proportions of infants achieving protective antibody concentrations to DTwP and PRP-T vaccine antigens were similar among the groups. In the second phase, the control group received 11PncTD at 18 weeks and the antibody concentrations were measured at 9 months in all children; 11PncTD induced a booster response to diphtheria in the control group. There was no negative interference from concomitant administration of new conjugate vaccines. In contrast, 11PncTD can boost the antibody response to the carrier proteins.

Antibodies, Bacterial↗
PubMed2006

Nasopharyngeal colonization: a target for pneumococcal vaccination.

The pneumococcal conjugate vaccine (PCV), licensed in 2000, is highly efficient in preventing serious disease caused by serotypes in the vaccine and also prevents symptomless colonization of the nasopharynx. Prevention of this first step in the infection cycle has important consequences: it reduces chances of spread of the infection and indirectly protects from disease. Through these indirect effects, the protection afforded by the vaccine extends to the whole population, including those not vaccinated (herd immunity). Already now, after 5 years of wide use of PCV for infant immunization in the USA, more cases are prevented through the indirect effects than by vaccine-induced immunity in those vaccinated. The extended protection increases the cost-effectiveness of PCV and should clearly encourage its use in poorly resourced countries. However, the accumulated experience also shows that the herd immunity, due to PCV, is partly offset by replacement of the vaccine serotypes by other, nonvaccine serotypes. Owing to the general reduced virulence of the latter, this has only had a modest effect on disease, but the possibility of more virulent nonvaccine serotypes arising cannot be ignored and should be the focus of continued surveillance.

Animals↗
PubMed2005

Development of natural antibodies to pneumococcal surface protein A, pneumococcal surface adhesin A and pneumolysin in Filipino pregnant women and their infants in relation to pneumococcal carriage.

For vaccine development it is important to know how antibodies develop after natural pneumococcal contacts. This work was done to receive information about the development of natural antibodies to pneumococcal surface protein A (PspA), pneumococcal surface adhesin A (PsaA) and pneumolysin (Ply), in early infancy and to receive information on how nasopharyngeal carriage of Streptococcus pneumoniae in infants affects the antibody concentrations. The antibody concentrations to PspA, PsaA and Ply were measured by EIA in serum samples of 51 pregnant women, in six consecutive serum samples of 173 infants (samples from 7 to 48 weeks of age), as well as in 39 cord bloods. Nasopharyngeal swabs were also collected from the infants and cultured for pneumococci. The geometric mean concentration (GMC) of anti-PspA and -Ply decreased until 18 weeks of age and started to increase thereafter, but was still at 48 weeks lower than in the mothers. The GMC of anti-PsaA in the infants increased significantly by age and reached the GMC of the mothers already at 14 weeks of age. The increase in antibody concentration in the infants was associated with pneumococcal carriage, but followed the different kinetics depending on the antigen. High maternal anti-Ply antibodies were negatively associated with the risk of pneumococcal carriage (OR 0.78, 0.61-0.99). This indicates that high maternal anti-Ply could be associated with lower pneumococcal carriage acquisition in infants.

Adhesins, Bacterial↗
PubMed2005

Economic evaluation of pneumococcal conjugate vaccination in Finland.

The aim of this study was to evaluate cost-effectiveness of pneumococcal conjugate vaccine (PCV7) in children <5 y of age. A Markov simulation model was used to compare the cost-effectiveness of 4 doses (assumed 50.5 euros per dose) of PCV7 with no intervention. Only direct effects of the vaccine were taken into account. In Finland, vaccination of a birth cohort of 57,500 healthy infants would potentially prevent annually 60 cases of invasive PD, 1,400 cases of pneumococcal pneumonia, 15,000 episodes of acute otitis media, 3,000 otological surgery procedures and 0.9 deaths in children aged <5 y. Investing 12.0 million euros to vaccinate a birth cohort would save annually 6.3 million euros in medical, and 2.0 million euros in productivity and other, costs. Therefore, investing 1 euros in a vaccination programme would return 0.53 euros in medical costs and 0.70 euros in societal costs. In the base case, vaccination would cost society 139,986 euros per life y gained. To achieve cost savings from a health care provider (societal) perspective, without considering herd effects or replacement phenomenon, the price of PCV7 should be 50% (70%) of the price used in the base case.

Child, Preschool↗
PubMed2004

Vaccinovigilance in Europe--need for timeliness, standardization and resources.

OBJECTIVE: To identify gaps in the systems for reporting adverse events following immunization (AEFI) in Europe by means of an interactive database constructed using a standardized approach. METHODS: A comparative survey was conducted in 1999-2000, using structured questionnaires addressed to the government authorities responsible for national immunization programmes and drug safety surveillance in all European Union (EU) Member States and in Norway and Switzerland. FINDINGS: The reporting of adverse vaccine reactions (AVRs) is covered by regulations in 13 of the 17 countries. Four countries have a specialized expert group with responsibility for vaccine safety. Only six professionals work full-time on vaccine safety in the 17 countries; in four of these countries the person is medically qualified. Fourteen countries have centralized reporting systems; in 14 countries the responsible authority is the drug regulatory agency. AEFI are reported using the procedure used for adverse drug reactions (ADRs) in all except four countries. The reporting form is not usually designed for vaccines and important details may therefore not be requested. Clinical definitions for vaccine reactions are not available. Twelve countries have appropriate official definitions for events or reactions, but the list of reportable events varies considerably between countries. The assessment of adverse vaccine reactions (AVRs) is hampered by lack of exact denominator data. Feedback to the rapporteurs was provided in 13 countries, but its quality was highly variable. CONCLUSION: The database facilitated a simple comparison of vaccinovigilance systems across participating countries. Most of the problems identified related to the reporting and analysis of AEFI could be solved through standardization and intensified international collaboration. On a national level, functional vaccinovigilance systems should be the shared responsibility of the drug regulatory authority and the national immunization programme. The resources for development and management of vaccine safety systems should be urgently improved.

Adverse Drug Reaction Reporting Systems↗
PubMed2004

Similar antibody concentrations in Filipino infants at age 9 months, after 1 or 3 doses of an adjuvanted, 11-valent pneumococcal diphtheria/tetanus-conjugated vaccine: a randomized controlled trial.

In Filipino infants, 1 dose of an adjuvanted, 11-valent pneumococcal conjugate vaccine (serotypes 1, 4, 5, 7F, 9V, 19F, and 23F conjugated to tetanus protein; and serotypes 3, 6B, 14, and 18C conjugated to diphtheria toxoid) administered alone at age 18 weeks (11PncTD1) elicited similar antibody concentrations at age 9 months as those elicited by 3 doses (11PncTD3) administered concomitantly with national program vaccines, at ages 6, 10, and 14 weeks. Geometric mean antibody concentrations ranged from 0.36 microg/mL (for serotype 18C) to 5.81 microg/mL (for serotype 4), for the 11PncTD1 vaccine, and from 0.32 microg/mL (for serotype 18C) to 5.01 microg/mL (for serotype 19F), for the 11PncTD3 vaccine. The proportion of infants with threshold antibody concentrations > or =0.35 microg/mL was also similar (ranges, 55.6%-100% for the 11PncTD1 vaccine and 42.9%-100% for the 11PncTD3 vaccine). The functional activity of antibodies expressed as opsonophagocytic activity titers was similar in the 11PncTD1 and 11PncTD3 groups. This finding is an important one for countries with financial constraints and high pneumococcal disease burden.

Adjuvants, Immunologic↗
PubMed2003

Safety and immunogenicity of three doses of an eleven-valent diphtheria toxoid and tetanus protein--conjugated pneumococcal vaccine in Filipino infants.

BACKGROUND: An 11-valent pneumococcal conjugate vaccine could provide significantly larger reduction in pneumococcal disease burden than the currently available 7-valent vaccine formulation in many countries. METHODS: In total, 50 infants were enrolled to this open, uncontrolled study, which evaluated the safety and immunogenicity of an aluminium adjuvanted 11-valent mixed-carrier diphtheria toxoid or tetanus protein-conjugated vaccine (11-PncTD) when administered in three doses at 6, 10 and 14 weeks of age simultaneously with DTwP//PRP-T and OPV vaccines in Filipino infants. RESULTS: The rates of local reactions between the two injection sites, those associated with the 11-PncTD vaccine and those with the DTwP//PRP-T were almost of equal frequency for all three vaccine doses except for induration, which was significantly more common in the DTP//PRP-T injection site. Fever was present in 39%, 22% and 21% of infants following each of the three doses. Antibody responses were determined by an enzyme immunoassay method before the first vaccination and after the three doses. The vaccine elicited a significant anti-pneumococcal polysaccharide antibody response against all serotypes included in the vaccine, except for type 14, for which the pre-vaccination geometric mean antibody concentration (GMC) was high (1.61 microg/ml). The GMCs one month after the vaccination series ranged from 1.1 micrograms/ml for type 6B to 23.4 microg/ml for type 4. CONCLUSION: The 11-PncTD vaccine is safe, well-tolerated and immunogenic. The effectiveness of the non-adjuvanted formulation of the vaccine in preventing pneumonia is currently being evaluated in the Philippines.

Diphtheria-Tetanus Vaccine↗
PubMed2003

Functional antibodies elicited by an 11-valent diphtheria-tetanus toxoid-conjugated pneumococcal vaccine.

The aluminium-adjuvanted 11-valent pneumococcal conjugate vaccine containing polysaccharides 1, 4, 5, 7F, 9V, 19F, and 23F (coupled to tetanus protein) and polysaccharides 3, 6B, 14, and 18C (coupled to diphtheria toxoid) elicits high antibody concentrations in Filipino infants when given at ages 6, 10, and 14 weeks and 9 months simultaneously with the national vaccination program. We evaluated functional activity of these antibodies by using a viable cell opsonophagocytic assay (OPA). The OPA titers correlated (r=0.53-0.74) with the respective antibody concentrations. The geometric mean OPA titers after 3 vaccine doses were 276.9 (serotype 4), 12.3 (serotype 6B), 46.0 (serotype 14), 119.3 (serotype 19F), and 206.3 (serotype 23F). The functionality of antibodies increased after the fourth dose of vaccine (i.e., the concentration required for in vitro killing of pneumococci decreased). Both the quantity and quality of antibodies are important in the evaluation of immunogenicity of pneumococcal vaccines.

Antibodies, Bacterial↗
PubMed2003

Correlation between the severity of infectious diseases in children and the ratio of serum amyloid A protein and C-reactive protein.

The aim of this study was to assess whether measurements of serum amyloid A protein (SAA) could provide additional information on the severity of acute infection beyond that obtained from C-reactive protein (CRP) assays. The SAA and CRP concentrations were analysed from the sera of 334 children hospitalized for suspected pneumonia, meningitis or sepsis. SAA significantly correlated with CRP (r = 0.682, p < 0.001) and did not alone provide any further clinically useful information. By contrast, the median ratio (and interquartile range) of SAA to CRP varied significantly between clinical conditions of different severity and was significantly lower in the patients who died [1.9 (0.0-8.9)] than in those who survived [6.8 (3.2-13.6)] (p = 0.001).

Acute Disease↗
PubMed2003

Report from a WHO working group: standard method for detecting upper respiratory carriage of Streptococcus pneumoniae.

BACKGROUND: Numerous studies evaluating the efficacy of conjugate pneumococcal vaccines are being conducted or planned throughout the world. Some of these studies are evaluating the effect of vaccine on nasopharyngeal (NP) carriage. METHODS: The World Health Organization established a Working Group composed of representatives from these trials and other NP colonization experts to establish core, standardized methods for the study of pneumococcal NP colonization that could be used in these trials. The intent was to reduce or eliminate variability in key methods which themselves could contribute to variability of observed pneumococcal NP colonization. In this way variability of vaccine effects between trials on NP colonization could more easily be analyzed for population or vaccine differences without the confounding effect caused by differences in study methodology. RESULTS: This paper presents the evidence base supporting the need for standardized NP colonization study methods, the methods themselves (Core Consensus Methods found in the electronic version of this article at www.pidj.com and on the WHO website at http://www.who.int/vaccines-research/rd/docsrd.shtml), including collection techniques, culture media, equipment, serotyping, storage of specimens and transport of isolates agreed on by the Working Group as well as a discussion of research priorities. CONCLUSIONS: The Core Consensus Methods provide a common methodology to conduct pneumococcal NP colonization studies with minimum interstudy method variability. The intention is to allow more meaningful comparisons of study results from conjugate pneumococcal vaccine trials.

Bacteriological Techniques↗
PubMed2003

Report from a WHO Working Group: standard method for detecting upper respiratory carriage of Streptococcus pneumoniae.

BACKGROUND: Numerous studies evaluating the efficacy of conjugate pneumococcal vaccines are being conducted or planned throughout the world. Some of these studies are evaluating the effect of vaccine on nasopharyngeal (NP) carriage. METHODS: The World Health Organization established a Working Group comprised of representatives from these trials and other NP colonization experts to establish core, standardized methods for the study of pneumococcal NP colonization that could be used in these trials. The intent was to reduce or eliminate variability in key methods which themselves could contribute to variability of observed pneumococcal NP colonization. In this way variability of vaccine effects between trials on NP colonization could more easily be analyzed for population or vaccine differences without the confounding effect caused by differences in study methodology. RESULTS: This paper presents the evidence base supporting the need for standardized NP colonization study methods, the methods themselves (Core Consensus Methods), including collection techniques, culture media, equipment, serotyping, storage of specimens and transport of isolates agreed on by the Working Group as well as a discussion of research priorities. CONCLUSIONS: The Core Consensus Methods provide a common methodology to conduct pneumococcal NP colonization studies with minimum interstudy method variability. The intention is to allow more meaningful comparisons of study results from conjugate pneumococcal vaccine trials.

Age Distribution↗
PubMed2003

Greater antibody responses to an eleven valent mixed carrier diphtheria- or tetanus-conjugated pneumococcal vaccine in Filipino than in Finnish or Israeli infants.

BACKGROUND: Antibody responses to pneumococcal conjugate vaccines may vary when administered in different populations or epidemiologic settings. Understanding the causes and significance of this variation could help to determine the number of doses and timing required for protection against pneumococcal diseases in each country. METHODS: This report compares antibody responses to aluminum-adjuvanted and nonadjuvanted mixed carrier 11-valent diphtheria- or tetanus-conjugated pneumococcal vaccine (11-PncTD) formulations when given at 6, 10 and 14 weeks and 9 months of age to Filipino infants (n = 51) and at 2, 4, 6 and 12 months of age to Finnish (n = 127) and Israeli (n = 124) infants. The study populations differ in their natural exposure to pneumococcus and risk factors for pneumococcal carriage and disease. RESULTS: Filipino and Israeli infants had slightly but significantly higher prevaccination geometric mean concentration (GMC) of antibodies than did the Finnish infants. After three doses of aluminum-adjuvanted 11-PncTD vaccine, the Filipino infants had 1.8 to 6.7 and 1.5 to 5.0 times higher GMC than the Finnish and Israeli infants, respectively, against pneumococcal serotypes conjugated to tetanus protein. The GMC of serotypes conjugated to diphtheria toxoid was 1.3 to 3.0 and 0.7 to 2.0 times the GMC in Finnish and Israeli infants, respectively. The nonadjuvanted vaccine formulation induced generally lower GMCs. CONCLUSIONS: The antibody responses to the tetanus-conjugated polysaccharides were considerably higher in the Filipino than in the Finnish or Israeli infants. This may be a result of several factors including the priming effect of tetanus toxoid given to pregnant women, early pneumococcal nasopharyngeal acquisition and genetic differences among populations.

Antibodies, Bacterial↗
PubMed2002

Antibody response to an eleven valent diphtheria- and tetanus-conjugated pneumococcal conjugate vaccine in Filipino infants.

BACKGROUND: Pneumococcal conjugate vaccines are intended to provide effective protection against pneumococcal infections, but very little information on antibody responses in infants living in countries with high pneumococcal disease burden exists. METHODS: In this study 50 healthy Filipino infants were enrolled at a village health center in Cabuyao to receive 11-valent diphtheria- and tetanus-conjugated pneumococcal vaccine at 6, 10 and 14 weeks of age (primary series) simultaneously with diphtheria-tetanus-whole cell pertussis/polyribosylribitol phosphate conjugated to tetanus toxoid, hepatitis B virus and oral poliovirus vaccines and at 9 months of age (booster dose) simultaneously with measles vaccine. The alum-adjuvanted study vaccine contained pneumococcal polysaccharide of serotypes 1, 4, 5, 7F, 9V, 19F and 23F conjugated to tetanus protein and pneumococcal polysaccharide of serotypes 3, 6B, 14 and 18C conjugated to diphtheria toxoid. Serum samples for enzyme immunoassay analyses were collected at 6, 10 and 14 weeks and 9 and 10 months of age. RESULTS: Very high geometric mean antibody concentrations (GMCs) against most pneumococcal serotypes were observed after the first three doses of vaccine (range, serotype 23F, 3.89 microg/ml to serotype 4, 23.41 microg/ml) with the exception of serotype 6B and 14, with GMCs of 1.12 and 2.18 microg/ml, respectively. The fourth dose increased the GMCs against most serotypes (range, serotype 14, 1.65 to serotype 19F, 33.43 microg/ml). The maternally derived antibodies did not decrease the response to the vaccine. CONCLUSIONS: This first pneumococcal conjugate vaccine study in Asia confirms that the 11-valent diphtheria- and tetanus-conjugated pneumococcal vaccine is highly immunogenic in Filipino infants. The GMCs against most pneumococcal serotypes were substantially higher than described with the same or other pneumococcal conjugate vaccines in other populations.

Antibody Formation↗