A 2-dose regimen of a recombinant hepatitis B vaccine with the immune stimulant AS04 compared with the standard 3-dose regimen of Engerix-B in healthy young adults.
An open-label randomized study was undertaken to compare a 2-dose regimen (Months 0 and 6) of hepatitis B surface antigen (HBsAg) vaccine formulated with a novel adjuvant (HBsAg/AS04) with a standard 3-dose regimen (Months 0, 1 and 6) of licensed recombinant HBsAg vaccine in terms of immunogenicity and reactogenicity when administered to healthy subjects aged between 15 and 40 y. At 1 and 6 months after the full vaccination course there was a 100% seroprotection rate (anti-HBs > or = 10 mIU/ml) with the HBsAg/AS04 vaccine, compared with a 99% response rate with the licensed vaccine. The corresponding geometric mean titres were significantly higher for the novel vaccine compared to the standard vaccine: 15,468 and 2,745 mIU/ml at Months 7 and 12 vs. 6,274 and 1,883 mIU/ml, respectively. There was a higher prevalence of local symptoms with the adjuvant vaccine (90% of doses) than with the standard vaccine (48% of doses). However, these symptoms (pain, swelling and redness) were predominantly of mild-to-moderate intensity and resolved rapidly without treatment. A 2-dose regimen of the new HBsAg/AS04 adjuvant vaccine therefore compared favourably to the standard regimen in healthy young adults. It is anticipated that the simplified vaccination schedule may improve compliance and reduce costs.
The validity of immunizations, made in due time in children aged up to 7 years in accordance with the approved immunization schedule, is analyzed in this work. The content of antibodies to diphtheria, tetanus and poliomyelitis antigens in children immunized in accordance with the old and new schedules has been studied. This study has revealed that the injection of adsorbed DPT vaccine to children aged 3-4 months induces fully valid immune response to all antigens under study. The level of measles and parotitis antibodies after the injections of measles and parotitis vaccines, introduced separately and simultaneously, has been measured. The simultaneous administration of these preparations did not decrease the levels of immunity to parotitis and measles.
In Canada, the pH1N1 influenza vaccine is recommended for children, particularly those less than 5 years of age or with chronic underlying disease. The pH1N1 vaccine, which contains residual allergenic egg white proteins, may pose a risk for vaccination of egg-allergic children.
To describe the outcome of pH1N1 influenza vaccine administration to egg-allergic children at risk for severe H1N1 disease.
Prospective observational cohort study. Children identified as at high risk for egg allergy and H1N1 influenza were vaccinated using a two-dose split protocol in a controlled medical setting. Children were given an initial test dose; if no reaction was noted, the remainder of the dose was administered and the children were followed for allergic reactions. Those who tolerated the split dose and required a second dose of vaccine were offered vaccination four weeks later as one injection.
Sixty-two egg-allergic children considered at high risk for H1N1 disease received the adjuvanted pH1N1 vaccine. Egg allergy was diagnosed both clinically by an allergist and using skin and/or serum IgE testing. Within one hour of immunization, 2 children developed hives, 1 had a vasovagal response and 1 had a hypo-responsive episode. Fourteen children received the second H1N1 dose and 1 developed erythema and itching. There were no anaphylactic reactions.
Administration of the adjuvanted pH1N1 vaccine in egg-allergic children at risk for severe H1N1 influenza was safe when performed in a two-dose split protocol in a controlled medical setting.
Published data related with comparison studies of safety, efficiency and some other properties of cold-adapted live influenza vaccine (LIV) and of inactivated influenza vaccine (IIV) are analyzed. LIV and IIV do not differ by systemic reactions after administration; however, it is not ruled out that there can be unfavorable reactions in vaccination of persons with allergy to the chicken-embryo proteins as well as in cases of persistence/reversion of cold-adapted strain observed in vaccination of persons with primary impairments of the immune system. There are no convincing data, up to now, on that LIV is superior to IIV in coping with influenza pandemics. The efficiency of LIV and IIV for children aged 3 years and more and for healthy adults is virtually identical. Additional controllable field comparative studies of LIV and IIV efficiency in immunization of elderly persons are needed. Limited data on LIV efficiency for children aged 2 months and more were obtained. The need in a 2-stage vaccination of all age group with the aim of ensuring responses to all 3 LIV components is, certainly, a LIV disadvantage. In case of IIV, the 2-stage vaccination is needed only for persons who were not ill with influenza. The intranasal LIV administration has, from the practical and psychological standpoints, an advantage before the IIV administration by syringe. The ability of LIV to protect from the drift influenza-virus variations could be its advantage before IIV; still, more research is needed to verify it. Transplantable cell lines meeting the WHO requirements could be an optimal substrate for the production of LIV and IIV. Children are the optimal age group for influenza prevention by cold-adapted LIV, whereas, IIV fits better for vaccination of adults and elderly persons.
In the Gothenburg study, 3,450 infants were randomly assigned to receive three subcutaneous injections of acellular pertussis vaccine consisting of peroxide-inactivated pertussis toxin with diphtheria and tetanus toxoids (DTP-toxoids) or DT-toxoids alone under blind conditions at three, five and 12 months of age. Safety of the vaccinations was assessed by direct contact with the families in the week following each injection. No serious vaccine-associated adverse reactions were observed, in either group. The frequency of fever and local reactions increased by dose. Redness and swelling were slightly but significantly more frequent in recipients of DTP-toxoids compared to the DT group.
