Vaccine
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Epidemic meningitis in Africa remains an important and unresolved public health problem. Bacteriologic and epidemiologic data collected over the past 30 years have consistently established the importance of Group A Neisseria meningitidis as the dominant etiologic agent. The meningococcal Group A capsule is the major virulence factor; it is a polysaccharide comprised of a repeating unit of partly O-acetylated alpha-1,6-linked N-acetylmannosamine phosphate. ⋯ A meningococcal A conjugate vaccine (MenAfriVac) has been developed and tested in Phase II clinical trials in Africa. The vaccine has been shown to be safe and to generate a sustained immunologic response with functional antibody 20 times higher than that seen with polysaccharide vaccine. Widespread use of such a vaccine is likely to generate herd immunity and to put an end to Group A meningococcal epidemics.
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Neisseria meningitidis is an important cause of bacterial meningitis and septicaemia with most disease caused by meningococci bearing serogroups A, B, C, Y and W-135 polysaccharides. Monovalent serogroup C conjugate vaccines have become established in the immunisation programmes in many countries and the first quadrivalent meningococcal vaccine, containing the polysaccharides from 4 of the serogroups A, C, Y and W-135 meningococci conjugated to a protein carrier was licensed in the US in 2005. This vaccine and others in development offer the potential to broaden population protection against meningococcal disease.
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The rapid evolution, genetic diversity, broad host range, and increasing human infection with avian influenza A (H5N1) viruses highlight the need for an efficacious cross-clade vaccine. Using the ferret model, we compared induction of cross-reactive immunity and protective efficacy of three single-clade H5N1 vaccines and a novel multiple-clade H5N1 vaccine, with and without MF59 adjuvant. Reverse genetics (rg) was used to generate vaccine viruses containing the hemagglutinin (HA) and neuraminidase genes of wild-type H5N1 viruses. ⋯ The multiple-clade vaccine was broadly immunogenic against clade 1 and 2 viruses. The rg-A/Vietnam/1203/04 vaccine (the currently stockpiled H5N1 vaccine) most effectively reduced upper respiratory tract virus shedding after challenge with clade 1 and 2 viruses. Importantly, all vaccines protected against lethal challenge with A/Vietnam/1203/04 virus and provided cross-clade protection.
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The objective of this study is to estimate the cost-effectiveness of mass vaccination of US infants with the recently available rotavirus vaccine, RotaTeq. We developed a dynamic transmission model of rotavirus to incorporate herd immunity into cost-effectiveness analysis. ⋯ We conclude that a universal rotavirus vaccine program in the US would cost $77.30 per case averted from the health care and give a net saving of $80.75 per case averted from the societal perspectives, respectively. The cost per QALY gained was found to be $104,610 when we considered child with one caregiver, making the rotavirus vaccination program a cost-effective intervention.
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We have evaluated health and economic benefits of a universal infant vaccination with two rotavirus vaccines registered in Italy, on the bases of the burden of rotavirus gastroenteritis (RVGE) in a birth cohort of 520,000 Italian infants followed until 5 years of age. Estimates from published and unpublished sources of disease burden, costs, vaccine coverage, efficacy trials of both vaccines, and price were used to estimate cost-effectiveness from the perspectives of the Italian National Health Service (NHS) and society. ⋯ On the contrary, the program would provide a net savings of 24,324,198 euro from the societal perspective. From the Italian NHS perspective, the break-even price per vaccination course should be reduced at least to 46.25 euro to achieve a zero cost-effectiveness ratio.