Live vaccines for Theileria parva: deployment in eastern, Central and Southern Africa. Proceedings of an FAO/OAU-IBAR/ILRI workshop

The aim of this workshop was to consider methods of immunisation against East Coast Fever (ECF) and other forms of T. parva infection using the infection and treatment method or infection without treatment, and to identify needs for further research to improve vaccine quality and suitability; to consider present and future demands for T. parva vaccine and how these can be met; to review recent progress in developing alternative vaccines for the control of theileriosis caused by T. parva, to consider related research needs, and to identify training and information needs. The workshop participants discussed the deployment of live ECF vaccines and focused on the problems associated with their delivery and the solutions to these problems. These proceedings provide a record of all the country presentations, invited papers, group discussions and recommendations of the workshop. Topics of discussion include production of Theileria parva stabilates and preparation of a composite stabilate for immunisation, application of molecular tools in support of development, standards for live vaccines, infection and delivery method, vaccine delivery, socio-economics and impact assessment, alternative vaccines, and training requirements for vaccine delivery

Modeling the public health impact of malaria vaccines for developers and policymakers

Efforts to develop malaria vaccines show promise. Mathematical model-based estimates of the potential demand, public health impact, and cost and financing requirements can be used to inform investment and adoption decisions by vaccine developers and policymakers on the use of malaria vaccines as complements to existing interventions. However, the complexity of such models may make their outputs inaccessible to non-modeling specialists. This paper describes a Malaria Vaccine Model (MVM) developed to address the specific needs of developers and policymakers, who need to access sophisticated modeling results and to test various scenarios in a user-friendly interface. The model's functionality is demonstrated through a hypothetical vaccine.; The MVM has three modules: supply and demand forecast; public health impact; and implementation cost and financing requirements. These modules include pre-entered reference data and also allow for user-defined inputs. The model includes an integrated sensitivity analysis function. Model functionality was demonstrated by estimating the public health impact of a hypothetical pre-erythrocytic malaria vaccine with 85% efficacy against uncomplicated disease and a vaccine efficacy decay rate of four years, based on internationally-established targets. Demand for this hypothetical vaccine was estimated based on historical vaccine implementation rates for routine infant immunization in 40 African countries over a 10-year period. Assumed purchase price was $5 per dose and injection equipment and delivery costs were$0.40 per dose.; The model projects the number of doses needed, uncomplicated and severe cases averted, deaths and disability-adjusted life years (DALYs) averted, and cost to avert each. In the demonstration scenario, based on a projected demand of 532 million doses, the MVM estimated that 150 million uncomplicated cases of malaria and 1.1 million deaths would be averted over 10 years. This is equivalent to 943 uncomplicate cases and 7 deaths averted per 1,000 vaccinees. In discounted 2011 US dollars, this represents $11 per uncomplicated case averted and$1,482 per death averted. If vaccine efficacy were reduced to 75%, the estimated uncomplicated cases and deaths averted over 10 years would decrease by 14% and 19%, respectively.; The MVM can provide valuable information to assist decision-making by vaccine developers and policymakers, information which will be refined and strengthened as field studies progress allowing further validation of modeling assumptions

The status of vaccine availability and associated factors in Tshwane government clinics

Vaccines have greatly contributed to the control of vaccine preventable diseases. The adoption of the Decade of Vaccines (DoV) by the World Health Assembly in 2011 is an indication of how the global community values the benefits of vaccines. Efforts by many countries to introduce new vaccines are a significant move towards attaining this vision. However, new vaccines put strain on vaccine supply chains. The immunization programme in South Africa has similar challenges, with indications of vaccine stock outs in clinics since the introduction of three new vaccines in 2009. This study set out to establish the status of availability of vaccines in Tshwane government clinics and associated factors. Method: A cross-sectional study was conducted in a sample of randomly selected government clinics in Tshwane health district of Gauteng province. Data was collected using a structured measurement instrument during a visit to each of the participating clinics. Data was collated and analysed using excel based software. Results: A total of 31 clinics participated. In the preceding 12 months, clinics experienced vaccine stock outs, especially of the 3 new vaccines: pneumococcal conjugate vaccine (PCV), rotavirus (RV) vaccine and Pentaxim ®. These were also out of stock for a long duration; for over 2 weeks in a majority of clinics. The causes of vaccine stock outs were: poor management of stock, depot out of stock, unreliable deliveries, lack of pharmacy assistants, and limited fridge capacity. Further burdening the situation is the emergency ordering system that does not function effectively. Conclusion: Significant vaccine shortages occur in Tshwane government clinics. It is recommended that the vaccine supply chain should be restructured and overhauled with the use of advances in technology. Urgent measures should be taken to address the identified causes of stock outs including ensuring reliable deliveries of stock and emergency orders

A systematic review and meta-analysis of fractional dose compared to standard dose inactivated polio vaccination in children

The World Health Organisation (WHO) recommends the introduction of at least one single dose of inactivated polio vaccine (IPV) in routine immunisation schedules to mitigate the risk of a polio virus type 2 reintroduction or re-emergence. As a result, there has been an increased demand and concurrent supply shortages of IPV worldwide resulting in poor access to IPV. With the phasing out of the oral polio vaccine and the pursuit of global eradication of polio, ensuring an adequate supply of IPV is of paramount importance. One of the strategies to improve access is the use of the fractional dose because of its dose sparing and cost reduction properties. This mini-dissertation presents a research protocol (Section A), scoping review (Section B) and journal formatted manuscript (Section C) for a systematic review and meta-analysis of fractional dose compared to standard dose inactivated polio vaccination in children. Section A describes the rationale for the review, eligibility criteria, the search strategy and methods for data extraction and analysis. Section B is a scoping review that details the journey towards eradication of polio, the current state of IPV demand and supply and further explains the rationale for performing the systematic review. Section C is a manuscript that gives the results of the review after performing the methods outlined in Section A. The results showed that as the number of IPV doses increased the seroconversion rates for fractional dose and full dose IPV approximated each other such that at three doses the rates were similar. In conclusion, there is no difference in seroconversion between three doses of fractional dose IPV and three doses of full dose IPV. With the current IPV shortages, using fractional dose IPV instead of the full dose IPV can stretch supplies and possibly lower the cost of polio vaccination

Vaccine

Immunizing pregnant women is a promising strategy to reduce infectious disease-related morbidity and mortality in pregnant women and their infants. Important pre-requisites for the successful introduction of new vaccines for immunization in pregnancy include political commitment and adequate financial resources: trained, committed and sufficient numbers of healthcare workers to deliver the vaccines; close integration of immunization programs with antenatal care and Maternal and Child Health services; adequate access to antenatal care by pregnant women in the country (especially in low and middle-income countries (LMIC)); and a high proportion of births occurring in health facilities (to ensure maternal and neonatal follow-up can be done). The framework needed to advance a vaccine program from product licensure to successful country-level implementation includes establishing and organizing evidence for anticipated vaccine program impact, developing supportive policies, and translating policies into local action. International and national coordination efforts, proactive planning from conception to implementation of the programs (including country-level policy making, planning, and implementation, regulatory guidance, pharmacovigilance) and country-specific and cultural factors must be taken into account during the vaccines introduction.CC999999/Intramural CDC HHS/United States2019-10-01T00:00:00Z31072733PMC67712797184vault:3228

Boosting the Immunization Workforce: Lessons from the Merck Vaccine Network - Africa

This report shares lessons learned from The Merck Company Foundation's decade of experience building immunization capacity in Africa. The Merck Vaccine Network -- Africa, a philanthropic initiative to train immunization managers in Kenya, Mali, Uganda, and Zambia, suggests seven key lessons that can help other funders, governments, and NGOs designing or implementing similar vaccine delivery training programs improve the effectiveness and sustainability of their work.Merck's experience designing and supporting the initiative can offer valuable lessons for other actors in the immunization and broader global health fields who are engaged in or planning similar work. Specifically, we identify seven forward-looking lessons that can increase the effectiveness and sustainability of programs to build the capacity of the vaccine workforce in developing countries:Conduct a rigorous needs assessment to anchor efforts in local needs and priorities;Perform ongoing monitoring and evaluation (M&E) to enable programs to adapt, improve, and generate evidence of impact to attract new partners and funding;Create a sustainability plan at the outset to ensure that program impact is maintained beyond the conclusion of initial funding;Embed programs into local health systems to ensure that investments leverage existing infrastructure, relationships, and resources, and that impact can be sustained beyond the life of the program;Employ locally-adapted curricula and appropriate teaching techniques to maximize transfer and retention of relevant knowledge;Incorporate supportive supervision into programs to ensure that transferred knowledge is maintained and acted upon;Facilitate and support regular convening and communication, enabling continuous learning for improvement.In addition to describing the approach taken by MVN-A and the results achieved in the four focus countries, this paper provides additional detail on each lesson, supported by case studies from the MVNA experience

Cost-eff ectiveness of female human papillomavirus vaccination in 179 countries: a PRIME modelling study

Background Introduction of human papillomavirus (HPV) vaccination in settings with the highest burden of HPV is not universal, partly because of the absence of quantitative estimates of country-specifi c eff ects on health and economic costs. We aimed to develop and validate a simple generic model of such eff ects that could be used and understood in a range of settings with little external support. Methods We developed the Papillomavirus Rapid Interface for Modelling and Economics (PRIME) model to assess cost-eff ectiveness and health eff ects of vaccination of girls against HPV before sexual debut in terms of burden of cervical cancer and mortality. PRIME models incidence according to proposed vaccine effi cacy against HPV 16/18, vaccine coverage, cervical cancer incidence and mortality, and HPV type distribution. It assumes lifelong vaccine protection and no changes to other screening programmes or vaccine uptake. We validated PRIME against existing reports of HPV vaccination cost-eff ectiveness, projected outcomes for 179 countries (assuming full vaccination of 12-year-old girls), and outcomes for 71 phase 2 GAVI-eligible countries (using vaccine uptake data from the GAVI Alliance). We assessed diff erences between countries in terms of cost-eff ectiveness and health eff ects. Findings In validation, PRIME reproduced cost-eff ectiveness conclusions for 24 of 26 countries from 17 published studies, and for all 72 countries in a published study of GAVI-eligible countries. Vaccination of a cohort of 58 million 12-year-old girls in 179 countries prevented 690 000 cases of cervical cancer and 420 000 deaths during their lifetime (mostly in low-income or middle-income countries), at a net cost of US$4 billion. HPV vaccination was very cost eff ective (with every disability-adjusted life-year averted costing less than the gross domestic product per head) in 156 (87%) of 179 countries. Introduction of the vaccine in countries without national HPV vaccination at present would prevent substantially more cases of cervical cancer than in countries with such programmes, although the disparity has narrowed since 2012. If 71 phase 2 GAVI-eligible countries adopt vaccination according to forecasts, then in 2070 GAVI Alliance-funded vaccination could prevent 200 000 cases of cervical cancer and 100 000 deaths in some of the highest-burden countries. Interpretation Large between-country disparities exist for HPV vaccination, with countries with the most to gain yet to introduce national HPV vaccination. Support from the GAVI Alliance could help to reduce such disparities, but a substantial burden will remain even after presently projected vaccine introductions

A review of typhoid fever transmission dynamic models and economic evaluations of vaccination.

Despite a recommendation by the World Health Organization (WHO) that typhoid vaccines be considered for the control of endemic disease and outbreaks, programmatic use remains limited. Transmission models and economic evaluation may be informative in decision making about vaccine programme introductions and their role alongside other control measures. A literature search found few typhoid transmission models or economic evaluations relative to analyses of other infectious diseases of similar or lower health burden. Modelling suggests vaccines alone are unlikely to eliminate endemic disease in the short to medium term without measures to reduce transmission from asymptomatic carriage. The single identified data-fitted transmission model of typhoid vaccination suggests vaccines can reduce disease burden substantially when introduced programmatically but that indirect protection depends on the relative contribution of carriage to transmission in a given setting. This is an important source of epidemiological uncertainty, alongside the extent and nature of natural immunity. Economic evaluations suggest that typhoid vaccination can be cost-saving to health services if incidence is extremely high and cost-effective in other high-incidence situations, when compared to WHO norms. Targeting vaccination to the highest incidence age-groups is likely to improve cost-effectiveness substantially. Economic perspective and vaccine costs substantially affect estimates, with disease incidence, case-fatality rates, and vaccine efficacy over time also important determinants of cost-effectiveness and sources of uncertainty. Static economic models may under-estimate benefits of typhoid vaccination by omitting indirect protection. Typhoid fever transmission models currently require per-setting epidemiological parameterisation to inform their use in economic evaluation, which may limit their generalisability. We found no economic evaluation based on transmission dynamic modelling, and no economic evaluation of typhoid vaccination against interventions such as improvements in sanitation or hygiene