A phase II, open-label, multicentre study to evaluate the immunogenicity and safety of an adjuvanted prepandemic (H5N1) influenza vaccine in healthy Japanese adults

<p>Abstract</p> <p>Background</p> <p>Promising clinical data and significant antigen-sparing have been demonstrated for a pandemic H5N1 influenza split-virion vaccine adjuvanted with AS03_A, an α-tocopherol-containing oil-in-water emulsion-based Adjuvant System. Although studies using this formulation have been reported, there have been no data for Japanese populations. This study therefore aimed to assess the immunogenicity and tolerability of a prepandemic (H5N1) influenza vaccine adjuvanted with AS03_Ain Japanese adults.</p> <p>Methods</p> <p>This open-label, single-group study was conducted at two centres in Japan in healthy Japanese males and females aged 20-64 years (n = 100). Subjects received two doses of vaccine, containing 3.75 μg haemagglutinin of the A/Indonesia/5/2005-like IBCDC-RG2 Clade 2.1 (H5N1) strain adjuvanted with AS03_A, 21 days apart. The primary endpoint evaluated the humoral immune response in terms of H5N1 haemagglutination inhibition (HI) antibody titres against the vaccine strain (Clade 2.1) 21 days after the second dose. Ninety five percent confidence intervals for geometric mean titres, seroprotection, seroconversion and seropositivity rates were calculated. Secondary and exploratory endpoints included the assessment of the humoral response in terms of neutralising antibody titres, the response against additional H5N1 strains (Clade 1 and Clade 2.2), as well as the evaluation of safety and reactogenicity.</p> <p>Results</p> <p>Robust immune responses were elicited after two doses of the prepandemic influenza vaccine adjuvanted with AS03_A. Overall, vaccine HI seroconversion rates and seroprotection rates were 91% 21 days after the second vaccination. This fulfilled all regulatory acceptance criteria for the vaccine-homologous HI antibody level. A substantial cross-reactive humoral immune response was also observed against the virus strains A/turkey/Turkey/1/2005 (Clade 2.2) and A/Vietnam/1194/2004 (Clade 1) after the second vaccine administration. A marked post-vaccination response in terms of neutralising antibody titres was demonstrated and persistence of the immune response was observed 6 months after the first dose. The vaccine was generally well tolerated and there were no serious adverse events reported.</p> <p>Conclusions</p> <p>The H5N1 candidate vaccine adjuvanted with AS03_Aelicited a strong and persistent immune response against the vaccine strain A/Indonesia/5/2005 in Japanese adults. Vaccination with this formulation demonstrated a clinically acceptable reactogenicity profile and did not raise any safety concerns in this population.</p> <p>Trial registration</p> <p>Clinicaltrials.gov NCT00742885</p

Parents' perceived vulnerability and perceived control in preventing Meningococcal C infection: a large-scale interview study about vaccination

<p>Abstract</p> <p>Background</p> <p>Parents' reported ambivalence toward large-scale vaccination programs for childhood diseases may be related to their perception of the risks of side-effects or safety of vaccination and the risk of contracting the disease. The aim of this study is to evaluate parents' perceptions of their child's risk contracting a Meningococcal C infection and parents' perceived control in preventing infection in relation to their evaluation of the safety, effectiveness and usefulness of vaccination.</p> <p>Methods</p> <p>In a large-scale interview study, a random sample of parents was interviewed after their children had received vaccination against Meningococcal C in a catch-up campaign. Questions were asked about the perceived relative vulnerability of their child contracting an infection, perceived control in preventing an infection, and parents' evaluation of the safety, usefulness and effectiveness of vaccination.</p> <p>Results</p> <p>61% of 2910 (N = 1763) parents who were approached participated. A higher perceived relative vulnerability of their own child contracting the disease was related to a more positive evaluation of the vaccination campaign, while a lower perceived vulnerability did not result in a more negative evaluation. A higher perceived control in being able to prevent an infection was, however, related to a more critical attitude toward the safety, usefulness and effectiveness of vaccination.</p> <p>Conclusion</p> <p>Perceived relative vulnerability contracting an infection and parents' perceived control in preventing an infection seem to influence parents' evaluation of the vaccination programme. Future studies should determine if, and under which circumstances, these perceptions also affect parents' vaccination behaviour and would be relevant to be taken into account when educating parents about vaccination.</p

Geinactiveerd trivalent poliomyelitisvaccin. Samenvatting van klinische documentatie. Deel IV

Abstract niet beschikbaarInactivated poliomyelitis vaccine, produced by the RIVM, has been evaluated for its immunogenic potential in humans in several countries in different vaccine compositions and in various vaccination regimes. A vaccine containing 40-8-32 DU/dose of poliovirus types, 1, 2 and 3 respectively, is considered suitable for use in humans. The vaccine is 90-100% effective after one dose given to 6-months-old infants and after 2 doses given to 2-months-old infants, when circulating antibodies are used as criterion. Although it is generally accepted that durable immunity is not only related to sero-immunity but also with immunologic memory, a third vaccination is advocated to induce longterm immunity. A vaccine of essentially the same antigenic composition and given in a two-dose regimen, has proven to be effective during an outbreak of paralytic poliomyelitis, caused by polio virus type 1. Observations of adverse events (AE) in vaccination trials, in which IPV produced by the RIVM was given in the control group and the absence of reported AE at RIVM's Medical Center Immunizations, indicate that AE of the present IPV are limited to local reactions and (undefined) irritability in a minority of recipients.RIV

Surveillance of diphteria, an increasingly rare disease

Abstract niet beschikbaarIn the past decades a worldwide strong fall in the incidence of diphteria has been observed. This decrement is generally attributed to the introduction of large scale immunization against diphteria. In countries with high immunization coverage in childhood small recent epidemics have mainly affected adults. One of the targets of the European region of the World Health Organization is the elimination of diphteria by the year 2000. The rarity of diphteria asks for highly effective surveillance. For this reason the present surveillance system should be optimized in order to reach and maintain the elimination goal. Diagnosis of diphteria requires in the first place awareness of its possible occurrence. Subsequently adequate swab and lab procedures are necessary for a successful isolation and identification of Corynebacterium diphteria. Standardized criteria for the clinical diagnosis are presented. Standardized procedures for taking adequate swabs for the culture and identification of the microorganism are given. The function of each concerned health worker and authority is discussed. In order to perform an effective surveillance of diphteria closed network on local, regional and national level with a central coordination is necessary. This can be achieved in the best way by a National Coordination Center. In this center all clinical, research and lab expertise on diphteria should be concentrated. Also all information on diphteria must be concentrated and has to be analysed. The functions of this center include the continuous monitoring of diphteria in the population by regular studies, blowing alarm in case of diphteria cases or epidemics and the performance of an effective assistance and/or efficacious handling in case of calamities. Furthermore, the center will perform the quality control of the surveillance system.RIV

Serologische evaluatie van een vereenvoudigd immunisatie schema in Burkina Faso. Rapport van een samenwerkingsproject uitgevoerd in april 1989

Abstract niet beschikbaarA cross-sectional serological survey involving 355 children was performed to study the immunogenicity of DPT-IPV vaccine and measles vaccine under tropical conditions. The vaccines were used in the EPI programme in three provinces in Burkina Faso, West-Africa. A two dose regimen is followed for DPT-IPV. A very high percentage of the group of 179 twice vaccinated children was antibody positive. In the 176 non-vaccinated children a substantial proportion had antibodies to polioviruses, most of them only to one type. This appears to be a sensitive parameter for the circulation of wild polio viruses in the environment.RIV

Multi-center studie naar simultane toediening van DKTP en Hib PRP-T vaccins. Deel 1. Immunogeniteit

Resultaten worden beschreven van een multi-center klinische studie naar antistofvorming na twee vaccinatieschemas met simultane en gecombineerde toediening van DKTP en Hib PRP-T vaccins. 543 zuigelingen werden gerecruteerd uit 42 consultatiebureaus voor zuigelingen in Apeldoorn, Capelle en Rotterdam. De antistofrespons tegen alle vaccin-antigenen was in beide studiegroepen voldoende voor bescherming hiertegen. Een matige, maar statistisch significante interferentie werd gevonden bij de tetanus antistoffen. Deze waren lager in de groep kinderen die gecombineerde injecties kreeg dan in de groep die de injecties apart kreeg. Deze negatieve beinvloeding moet worden geinterpreteerd in het licht van de voordelen van gecombineerde toediening van deze belangrijke vaccins, waardoor het aantal injecties kan worden verminderd.Results are presented of a multi-center clinical study into the antibody formation following two vaccination regimens with simultaneous and combined administration of DPT-IPV and Hib PRP-T vaccines. 543 infants were recruited from 42 baby clinics in Apeldoorn, Capelle and Rotterdam. The antibody responses to all vaccine antigens were considered to be sufficient for protection on both study groups. A moderate but statistically significant interference was found with regard to tetanus antibodies, being lower in children who received combined injections than in children who received the separate injections. This negative interference should be interpreted in the light of the advantages of the combined administration of these important vaccines and thus of reducing the number of injections.IG