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1.
Adoption of new vaccines in developing countries is critical to reducing child mortality and meeting Millennium Development Goal 4. However, such introduction has historically suffered from significant delays that can be attributed to various factors including (i) lack of recognition of the value of a vaccine, (ii) factors related to weak health systems, and (iii) policy considerations. Recently, the Global Alliance for Vaccines and Immunization (GAVI) supported efforts to accelerate the introduction of Haemophilus influenzae type b (Hib) vaccines in developing countries, which resulted in a significant surge in vaccine adoption by these countries. The experience with Hib vaccines, as well as similar efforts by GAVI to support the introduction of new pneumococcal and rotavirus vaccines, provides a strategy for new vaccine adoption that is reviewed in this paper, providing a useful model to help accelerate the uptake of other life-saving vaccines. This strategy addresses barriers for vaccine adoption by focusing on three major areas: (i) communications to increase awareness about the various factors needed for evidence-based decisions that meet a country's health goals; (ii) research activities to answer key questions that support vaccine introduction and long-term programme sustainability; and (iii) coordination with the various stakeholders at global, regional and country levels to ensure successful programme implementation.  相似文献   

2.
Global immunization programmes have achieved some remarkable successes. In 1977, Frank Fenner's Commission declared smallpox to have been eradicated by an 11-year-long intensive campaign. The Expanded Programme on Immunization encompassed six important childhood vaccines and reached over three-quarters of the world's children. Polio eradication has gone remarkably well, with only 10 out of 200 countries reporting residual cases. But amidst all the good news, there is also bad news. Coverage is variable; infrastructure is crumbling; and newer vaccines are not being incorporated in many country programmes. The Bill and Melinda Gates Foundation has introduced a new dynamic here. From their initial gift of $100 million in December 1998, their commitment to date is US$1.5 billion - and rising. At the centre is a Global Children's Vaccine Fund which permitted the launch, in January 2000, of the Global Alliance for Vaccines and Immunization. This is targeted to the 74 poorest countries of the world and is designed to improve vaccination infrastructure, to purchase newer vaccines and to support research and development. Even before we know how successful this programme will be, it has had its imitators. The Global Fund to Fight AIDS, TB and Malaria borrowed many concepts from GAVI. The Global Alliance for Improved Nutrition announced in May 2002 does so as well, and is heavily supported by Gates. Highly effective parasite control programmes antedate all this but will be much strengthened. However, we still face a sizeable budgetary gap both for research and for bringing the best advances to all people who need them.  相似文献   

3.
Levin A  Fang A  Hansen PM  Pyle D  Dia O  Schwalbe N 《PloS one》2010,5(9):e12986
This paper presents the findings of a study to assess the effectiveness and sustainability of a GAVI (Global Alliance of Vaccines and Immunization) sponsored, time-limited Injection Safety (INS) support. The support came in two forms: 1) in-kind, in the form of AD syringes and safety boxes, and 2) in cash, for those countries that already had a secure, multi-year source of AD syringes and safety boxes, but proposed to use INS support to strengthen their injection safety activities. In total, GAVI gave INS support for a three-year period to 58 countries: 46 with commodities and 12 with cash support. To identify variables that might be associated with financial sustainability, frequencies and cross-tabulations were run against various programmatic and socio-economic variables in the 58 countries. All but two of the 46 commodity-recipient countries were able to replace and sustain the use of AD syringes and safety boxes after the end of their GAVI INS support despite the fact that standard disposable syringes are less costly than ADs (10-15 percent differential). In addition, all 12 cash-recipient countries continued to use AD syringes and safety boxes in their immunization programs in the years following GAVI INS assistance. At the same time, countries were often not prepared for the increased waste management requirements associated with the use of the syringes, suggesting the importance of anticipating challenges with the introduction of new technologies. The sustained use of AD syringes in countries receiving injection safety support from GAVI, in a majority of cases through government financing, following the completion of three years of time-limited support, represents an early indication of how GHPs can contribute to improved health outcomes in immunization safety in the world's poorest countries in a sustainable way.  相似文献   

4.
Increased international support for both research into new vaccines and their deployment in developing countries has been evident over the past decade. In particular, the GAVI Alliance has had a major impact in increasing uptake of the six common infant vaccines as well as those against hepatitis B and yellow fever. It further aims to introduce pneumococcal and rotavirus vaccines in the near future and several others, including those against human papillomavirus, meningococcal disease, rubella and typhoid not long after that. In addition, there is advanced research into vaccines against malaria, HIV/AIDS and tuberculosis. By 2030, we may have about 20 vaccines that need to be used in the developing world. Finding the requisite funds to achieve this will pose a major problem. A second and urgent question is how to complete the job of global polio eradication. The new strategic plan calls for completion by 2013, but both pre-eradication and post-eradication challenges remain. Vaccines will eventually become available beyond the field of infectious diseases. Much interesting work is being done in both autoimmunity and cancer. Cutting across disease groupings, there are issues in methods of delivery and new adjuvant formulations.  相似文献   

5.

Background

Adoption of new and underutilized vaccines by national immunization programs is an essential step towards reducing child mortality. Policy decisions to adopt new vaccines in high mortality countries often lag behind decisions in high-income countries. Using the case of Haemophilus influenzae type b (Hib) vaccine, this paper endeavors to explain these delays through the analysis of country-level economic, epidemiological, programmatic and policy-related factors, as well as the role of the Global Alliance for Vaccines and Immunisation (GAVI Alliance).

Methods and Findings

Data for 147 countries from 1990 to 2007 were analyzed in accelerated failure time models to identify factors that are associated with the time to decision to adopt Hib vaccine. In multivariable models that control for Gross National Income, region, and burden of Hib disease, the receipt of GAVI support speeded the time to decision by a factor of 0.37 (95% CI 0.18–0.76), or 63%. The presence of two or more neighboring country adopters accelerated decisions to adopt by a factor of 0.50 (95% CI 0.33–0.75). For each 1% increase in vaccine price, decisions to adopt are delayed by a factor of 1.02 (95% CI 1.00–1.04). Global recommendations and local studies were not associated with time to decision.

Conclusions

This study substantiates previous findings related to vaccine price and presents new evidence to suggest that GAVI eligibility is associated with accelerated decisions to adopt Hib vaccine. The influence of neighboring country decisions was also highly significant, suggesting that approaches to support the adoption of new vaccines should consider supply- and demand-side factors. Please see later in the article for the Editors'' Summary  相似文献   

6.
Thanks to the Global Alliance for Vaccines and Immunization (GAVI), the Vaccine Fund and the Bill & Melinda Gates Foundation, the global health community has made enormous progress in providing already existing vaccines to developing countries. However, there still exists a gap to develop vaccines for which there is no market in the Western world, owing to low economic incentives for the private sector to justify the investments necessary for vaccine development. In many cases, industry has the technologies, but lacks the impetus to direct resources to develop these vaccine products. The present emergency with the Ebola vaccine provides us an excellent example where a vaccine was feasible several years ago, but the global health community waited for a humanitarian disaster to direct efforts and resources to develop this vaccine. In the beginning of 2015, the first large-scale trials of two experimental vaccines against Ebola virus disease have begun in West Africa. During the past few years, several institutions have dedicated efforts to the development of vaccines against diseases present only in low-income countries. These include the International Vaccine Institute, the Novartis Vaccines Institute for Global Health, the Hilleman Institute, the Sabin Vaccine Institute and the Infectious Disease Research Institute. Nevertheless, solving this problem requires a more significant global effort than that currently invested. These efforts include a clear policy, global coordination of funds dedicated to the development of neglected disease and an agreement on regulatory strategies and incentives for the private sector.  相似文献   

7.
Although vaccines have widely been regarded as the most cost-effective way to improve public health, for some organisms new technological advances in vaccine design and delivery, incurring additional developmental costs, will be essential. These organisms are typically those for which natural immunity is either slow to develop or does not develop at all. Clearly, such organisms have evolved strategies to evade immune responses and innovative approaches will be required to induce a type of immune response which is both different to that which develops naturally and is effective. This article describes some approaches to develop vaccines for two such organisms (malaria parasites and Streptococcus pyogenes (group A Streptococcus)) that are associated with widespread mortality and morbidity, mostly in the poorest countries of the world. At this stage, the challenges are primarily scientific, but if these hurdles are surmounted then the challenges will become financial ones--developing much needed vaccines for people least able to afford them.  相似文献   

8.
Several techniques are used to estimate whether investing in vaccines and immunization is worthwhile, including cost analysis, cost-benefit analysis, cost-effectiveness analysis, and cost-utility analysis. At least 162 published economic evaluations of vaccines have been carried out from 1969 to 1998. They consistently show that immunization is an excellent investment--highly cost-effective and usually cost-saving--for vaccines that are currently recommended for universal use. Although prices of newer vaccines are higher than prices of traditional vaccines, they are still highly cost-effective. The World Health Organization, UNICEF, and vaccine manufacturers have developed approaches to make newer vaccines available to developing countries at reduced prices. Sustainability of immunization programs (the ability of a country to continue its immunization program in the absence of external support) is an increasingly important goal. However, external assistance will be essential in the short term to ensure that all the world's people benefit fully from the new vaccines.  相似文献   

9.

Background

A major effort to introduce new vaccines into poor nations of the world was initiated in recent years with the help of the GAVI alliance. The first vaccines introduced have been the Haemophilus influenzae type B (Hib) and the hepatitis B (Hep B) vaccines. The introduction of these vaccines during the first phase of GAVI''s operations demonstrated considerable variability. We set out to study the factors affecting the introduction of these vaccines. The African Region (AFRO), where new vaccines were introduced to a substantial number of countries during the first phase of GAVI''s funding, was selected for this study.

Methodology/Principal Findings

GAVI-eligible AFRO countries with a population of 0.5 million or more were included in the study. Countries were analyzed and compared for new vaccine introduction, healthcare indicators, financial indicators related to healthcare and country-level Governance Indicators, using One Way ANOVA, correlation analysis and Qualitative Comparative Analysis (QCA). Introduction of new vaccines into AFRO nations was associated primarily with high country-level Governance Indicator scores. The use of individual Governance Indicator scores, as well as a combined Governance Indicator score we developed, demonstrated similar results.

Conclusions/Significance

Our study results indicate that good country-level governance is an imperative pre-requisite for the successful early introduction of new vaccines into poor African nations. Enhanced support measures may be required to effectively introduce new vaccines to countries with low governance scores. The combined governance score we developed may thus constitute a useful tool for helping philanthropic organizations make decisions regarding the type of support needed by different countries to achieve success.  相似文献   

10.
Vaccines are one of the most successful public health achievements of the last century. Systematic immunisation programs have reduced the burden of infectious diseases on a global scale. However, there are limitations to the current technology, which often requires costly infrastructure and long lead times for production. Furthermore, the requirement to keep vaccines within the cold-chain throughout manufacture, transport and storage is often impractical and prohibitively expensive in developing countries—the very regions where vaccines are most needed. In contrast, plant-made vaccines (PMVs) can be produced at a lower cost using basic greenhouse agricultural methods, and do not need to be kept within such narrow temperature ranges. This increases the feasibility of developing countries producing vaccines locally at a small-scale to target the specific needs of the region. Additionally, the ability of plant-production technologies to rapidly produce large quantities of strain-specific vaccine demonstrates their potential use in combating pandemics. PMVs are a proven technology that has the potential to play an important role in increasing global health, both in the context of the 2015 Millennium Development Goals and beyond.  相似文献   

11.
Since the first licensure of the Sabin oral polio vaccine more than 50 years ago, only eight enteric vaccines have been licensed for four disease indications, and all are given orally. While mucosal vaccines offer programmatically attractive tools for facilitating vaccine deployment, their development remains hampered by several factors:
  • — limited knowledge regarding the properties of the gut immune system during early life;
  • — lack of mucosal adjuvants, limiting mucosal vaccine development to live-attenuated or killed whole virus and bacterial vaccines;
  • — lack of correlates/surrogates of mucosal immune protection; and
  • — limited knowledge of the factors contributing to oral vaccine underperformance in children from developing countries.
There are now reasons to believe that the development of safe and effective mucosal adjuvants and of programmatically sound intervention strategies could enhance the efficacy of current and next-generation enteric vaccines, especially in lesser developed countries which are often co-endemic for enteric infections and malnutrition. These vaccines must be safe and affordable for the world''s poorest, confer long-term protection and herd immunity, and must be able to contain epidemics.  相似文献   

12.
Recently retired as head of the Global Alliance for Vaccines and Immunization (GAVI) secretariat and as a health advisor to leading global entities, Tore Godal is now a Special Advisor to the Norwegian Prime Minister. He is nevertheless continuing to fight for better global health, cogently articulating the needs of the world's poor and disadvantaged. He is a leading leprosy expert, ex-director of the world's premier agency for research and training in tropical diseases, instigator and prime mover of some global innovative public-private health sector partnerships, adept fund mobilizer, and advocate of the 'let's get it done' school of leadership. Few individuals are, therefore, more experienced or better suited for such a crucial and much-needed role.  相似文献   

13.
Vaccines are clearly the most effective means of preventing infectious diseases and have been particularly successful in controlling viral infection. For example, global small-pox eradication has been the greatest achievement in this regard. However, many existing vaccines are not efficient and there are many diseases against which vaccines are not available at all.  相似文献   

14.
Vaccines have been one of the major revolutions in the history of mankind and, during the twentieth century, they eliminated most of the childhood diseases that used to cause millions of deaths. In the twenty-first century, vaccines will also play a major part in safeguarding people's health. Supported by the innovations derived from new technologies, vaccines will address the new needs of a twenty-first century society characterized by increased life expectancy, emerging infections and poverty in low-income countries.  相似文献   

15.
The successful use of Bacillus anthracis as a lethal biological weapon has prompted renewed research interest in the development of more effective vaccines against anthrax. The disease consists of three critical components: spore, bacillus, and toxin, elimination of any of which confers at least partial protection against anthrax. Current remedies rely on postexposure antibiotics to eliminate bacilli and pre- and postexposure vaccination to target primarily toxins. Vaccines effective against toxin have been licensed for human use, but need improvement. Vaccines against bacilli have recently been developed by us and others. Whether effective vaccines will be developed against spores is still an open question. An ideal vaccine would confer simultaneous protection against spores, bacilli, and toxins. One step towards this goal is our dually active vaccine, designed to destroy both bacilli and toxin. Existing and potential strategies towards potent and effective anthrax vaccines are discussed in this review.  相似文献   

16.
Lund A  Deboer DJ 《Mycopathologia》2008,166(5-6):407-424
Dermatophytosis is a relatively common disease in many countries occurring endemically both in companion and food animals. Fungi belonging to the genera Trichophyton and Microsporum are most often isolated from clinical cases. Measures to control and prevent dermatophytosis include sanitation, hygienic measures and treatment. In some countries, successful control and eradication have been achieved by mass vaccination of cattle and fur-bearing animals. Vaccines containing live attenuated cells of the fungus stimulate a cell-mediated immune response conferring long-lasting protection against subsequent challenge by the homologous fungus. A delayed type hypersensitivity (DTH) skin test using appropriate dermatophyte antigens is suitable to assess the response. Inactivated dermatophyte vaccines are available for use in cattle, horse, dog, and cat in some countries. However, the scientific literature is scarce making it difficult to conclude on efficacy and appropriate use. Current vaccines are all first generation vaccines. Attempts have been made to prepare subunit vaccines based on new knowledge about virulence factors like the keratinases, so far with limited success. Candidate antigens must be able to stimulate a strong T helper 1 cell response and future research should focus on identification of major T-cell epitopes that specifically elicit a DTH reaction. Dermatophytosis is a zoonotic disease. In Norway and a few other countries, systematic vaccination against cattle ringworm has almost eliminated the disease, and ringworm in man caused by T. verrucosum is almost nonexistent. A similar benefit could be expected if a safe and efficacious vaccine was available for Microsporum canis infection in cats and dogs.  相似文献   

17.
The development of new methods of administering coccidiosis vaccines has facilitated their use in the hatchery and thereby improved prospects for the economic vaccination of broilers. The acquisition of protective immunity to Eimeria species is boosted by further exposure to infection after vaccination. Factors that affect the reproductive efficiency of non-attenuated and attenuated vaccines are considered and the key role that oocyst production plays in establishing and maintaining uniform immunity in a flock of chickens is discussed. In addition to immunisation, a possible advantage to the application of certain vaccines is that their use could repopulate poultry houses with drug-sensitive organisms. Theoretical rotation programmes in which the use of drugs is alternated with that of vaccines are described. Variability of the cross-protective immune response between strains of the same species should be considered during vaccine development and subsequent use. The significance of less common species of Eimeria, not included in all vaccines, also needs to be assessed. An important consideration is the occurrence of pathogens other than Eimeria (such as the bacterium Clostridium) in flocks given coccidiosis vaccines and the methods by which they might be controlled. More research is required into the relationship between bacterial and viral infections of poultry and coccidiosis vaccination. Vaccines need to be developed that are simple to apply and cost effective for use in areas of the world where small-scale poultry production is commonplace. In the near future it is likely that more live vaccines based upon oocysts derived from attenuated strains of Eimeria will be developed but in the longer term vaccines will be based on the selective presentation to the host of specific molecules that can induce protective immunity. This achievement will require significant investment from the private and public sectors, and, if successful, will facilitate the sustainable control of coccidiosis in poultry production.  相似文献   

18.
BackgroundThe rise in dengue fever cases and the absence of dengue vaccines will likely cause governments to consider various types of effective means for controlling the disease. Given strong public interests in potential dengue vaccines, it is essential to understand the private economic benefits of dengue vaccines for accelerated introduction of vaccines into the public sector program and private markets of high-risk countries.Conclusions/SignificanceKnowing that dengue vaccines are not yet available, our study provides critical information to both public and private sectors. The study results can be used to ensure broad coverage with an affordable price and incorporated into cost benefit analyses, which can inform prioritization of alternative health interventions at the national level.  相似文献   

19.
Salmonella Typhi, first isolated in 1884, results in infection of the intestines and can end in death and disability. Due to serious adverse events post vaccination, whole cell killed vaccines have been replaced with new generation vaccines. The efficacy of Vi polysaccharide (ViPS) vaccine, a new generation, single-dose intramuscular typhoid vaccine was assessed in Nepal in 1987. However, despite the availability of ViPS vaccine for more than 25 years, Nepal has one of the highest incidence of typhoid fever. Therefore we collected information from hospitals in the Kathmandu Valley from over the past five years. There were 9901 enteric fever cases between January 2008 and July 2012. 1,881 of these were confirmed typhoid cases from five hospitals in the Kathmandu district. Approximately 70% of the cases involved children under 15 years old. 1281 cases were confirmed as S. Paratyphi. Vaccines should be prioritized for control of typhoid in conjunction with improved water and sanitation conditions in Nepal and in endemic countries of Asia and Africa.  相似文献   

20.
In most cases, a successful vaccine must induce an immune response that is better than the response invoked by natural infection. Vaccines are still unavailable for several bacterial infections and vaccines to prevent such infections will be best developed on the basis of our increasing insights into the immune response. Knowledge of the signals that determine the best possible acquired immune response against a given pathogen - comprising a profound T- and B-cell memory response as well as long-lived plasma cells - will provide the scientific framework for the rational design of novel antibacterial vaccines.  相似文献   

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