Vaccine
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Only viruses of the Influenzavirus A genus have been isolated from birds and termed avian influenza [AI] viruses, but viruses with all 16 haemagglutinin [H1-H16] and all 9 neuraminidase [N1-N9] influenza A subtypes in the majority of possible combinations have been isolated from avian species. Influenza A viruses infecting poultry can be divided into two groups. The very virulent viruses causing highly pathogenic avian influenza [HPAI], with flock mortality as high as 100%. ⋯ Since the 1990s AI infections due to two subtypes have been widespread in poultry across a large area of the World. LPAI H9N2 appears to have spread across the whole of Asia in that time and has become endemic in poultry in many of the affected countries. However, these outbreaks have tended to have been overshadowed by the H5N1 HPAI virus, initially isolated in China, that has now spread in poultry and/or wild birds throughout Asia and into Europe and Africa, resulting in the death or culling of hundreds of millions of poultry and posing a significant zoonosis threat.
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Randomized Controlled Trial
Immunogenicity of reduced antigen content tetanus-diphtheria-acellular pertussis vaccine in adolescents as a sixth consecutive dose of acellular pertussis-containing vaccine.
Three hundred and nineteen adolescents aged 10-12 years who had been previously vaccinated with five doses of acellular pertussis-containing vaccines received single doses of Tdap (reduced-antigen-content tetanus, diphtheria, acellular pertussis) and hepatitis A vaccines in a double-blind crossover trial. Long-term antibody persistence following vaccination with Tdap at pre-school age was similar to that following vaccination with DTaP (diphtheria-tetanus-acellular pertussis). After the sixth dose booster, Tdap induced a vigorous immune response, consistent with protection against diphtheria, tetanus and pertussis diseases.
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Clinical trials have shown prophylactic human papillomavirus (HPV) vaccines to be effective against infection and disease. We examined whether HPV vaccination has the potential to be cost-effective. ⋯ Vaccinating adolescent girls against HPV is likely to be cost-effective. The main benefit of vaccination will be in reducing CC mortality. However, unless screening is modified, the treatment costs saved through vaccination will be insignificant compared to the cost of HPV immunization.
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A ferret model of severe acute respiratory syndrome (SARS)-CoV infection was used to evaluate the efficacy of an adenovirus vaccine. Animals were subjected to heterologous prime-boost using vectors from human serotype 5 and chimpanzee derived adenoviruses (human AdHu5 and chimpanzee AdC7) expressing spike protein followed by intranasal challenge with SARS-CoV. ⋯ The same prime-boost strategy was effective in rhesus macaques in eliciting SARS-CoV specific immune responses. These data indicate that a heterologous adenovirus-based prime-boost vaccine strategy could safely stimulate strong immunity that may be needed for complete protection against SARS-CoV infection.
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Despite preventive efforts, influenza epidemics are responsible for substantial morbidity and mortality every year in the United States (US). Vaccination strategies to reduce disease burden have been implemented. However, no previous studies have systematically estimated the annual economic burden of influenza epidemics, an estimate necessary to guide policy makers effectively. ⋯ These results highlight the enormous annual burden of influenza in the US. While hospitalization costs are important contributors, lost productivity from missed work days and lost lives comprise the bulk of the economic burden of influenza.