Human vaccines
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Early rotavirus vaccine adopter countries in the Americas, Europe, and in Australia have documented substantial declines in rotavirus disease burden following the introduction of vaccination. However, the full public health impact of rotavirus vaccines has not been realized as they have not been introduced into routine immunization programs in countries of Africa and Asia with the highest rotavirus disease morbidity and mortality burden. In this article, we review the epidemiology of rotavirus disease, the development and current status of rotavirus vaccines including newly available vaccine impact data from early-introducer countries, and future priorities for implementation and monitoring of rotavirus vaccination programs in developing countries.
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Vaccination is considered the most effective strategy to control influenza and becomes particularly important when a new subtype or distantly related strain of virus enters the human population causing a world-wide epidemic or "pandemic". Depending upon the virulence of the emerging virus, a lack of pre-existing immunity can lead to overwhelming morbidity and deaths ranging in the millions. While the correlates of immunity to influenza are yet to be fully understood, our experience with vaccines over many decades enables pre-pandemic planning to develop strategies to minimise the impact of a human pandemic. This review explores developing pandemic and pre-pandemic vaccines in the context of highly virulent avian H5N1 virus and the influenza H1N1 pandemic of 2009.
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Prior to widespread vaccination, Haemophilus influenzae type b was a leading cause of severe childhood bacterial infection, including meningitis, worldwide. Over the last decade the world has taken great strides towards controlling Hib disease through routine use of conjugate vaccines in developed and developing countries. ⋯ Questions remain as to the most effective and efficient schedule of primary doses, the need for a booster dose, and the implications of using combination vaccines. Here, we present a synthesis of data supporting various Hib vaccine schedules, with a focus on the implications for developing countries.
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Prior to the introduction of killed whole cell pertussis vaccine [wP] in the 1940s, whooping cough was a major cause of infant death worldwide. Widespread vaccination of children with this vaccine caused a significant reduction in mortality. However in the 1990s and now more recently, there has been a resurgence of pertussis in several countries even in populations previously vaccinated with an acellular pertussis vaccine [aP]. In this review, we describe the epidemiology of whooping cough, the vast array of virulence factors produced by this pathogen potentially contributing to the resurgence of pertussis even in previously vaccinated populations of infants and children, history of whooping cough prophylaxis, possible mechanisms of immunity, lack of availability of a suitable non-toxic adjuvant capable of inducing both arms of the immune response, and the current status of development of improved vaccines with potential to induce longer-lasting protection, than is currently possible with the wP or aP vaccines, against whooping cough.
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Ebolavirus is a highly infectious pathogen with a case fatality rate as high as 90%. Currently there is a lack of licensed Ebolavirus vaccines as well as pre- and post-exposure treatments. Recent increases in the frequency of natural human Ebolavirus infections and its potential use as a bioterrorism agent makes vaccine development a priority for many nations. ⋯ These include replication-deficient adenovirus vectors, replication-competent VSV, HPIV-3 vectors and virus-like particle preparations. Recent advances in the generation of effective post-exposure immunization strategies highlight the possibility of developing a single dose vaccine that will confer full protection in humans following Ebolavirus exposure. Post-exposure protection is particularly important in outbreak and biodefense settings, as well as clinical and laboratory settings in the case of accidental exposure.