Evidence-based decision-making for vaccine introductions: Overview of the ProVac International Working Group's experience

INTRODUCTION

Pan American Health Organization's (PAHO) ProVac Initiative aims to strengthen countries' technical capacity to make evidence-based immunization policy. With financial support from the Bill and Melinda Gates Foundation, PAHO established the ProVac International Working Group (IWG), a platform created for two years to transfer the ProVac Initiative's tools and methods to support decisions in non-PAHO regions.

METHODS

In 2011, WHO Regional Offices and partner agencies established the IWG to transfer the ProVac framework for new vaccine decision support, including tools and trainings to other regions of the world. During the two year period, PAHO served as the coordinating secretariat and partner agencies played implementing or advisory roles.

RESULTS

Fifty nine national professionals from 17 countries received training on the use of economic evaluations to aid vaccine policy making through regional workshops. The IWG provided direct technical support to nine countries to develop cost-effectiveness analyses to inform decisions. All nine countries introduced the new vaccine evaluated or their NITAGs have made a recommendation to the Ministry of Health to introduce the new vaccine.

DISCUSSION

Developing countries around the world are increasingly interested in weighing the potential health impact due to new vaccine introduction against the investments required. During the two years, the ProVac approach proved valuable and timely to aid the national decision making processes, even despite the different challenges and idiosyncrasies encountered in each region. The results of this work suggest that: (1) there is great need and demand for technical support and for capacity building around economic evaluations; and (2) the ProVac method of supporting country-owned analyses is as effective in other regions as it has been in the PAHO region.

CONCLUSION

Decision support for new vaccine introduction in low- and middle-income countries is critical to guiding the efficient use of resources and prioritizing high impact vaccination programs.

An analysis of government immunization program expenditures in lower and lower middle income countries 2006-12

Financing is becoming increasingly important as the cost of immunizing the world's children continues to rise. By 2015, that cost will likely exceed US$60 per infant as new vaccines are introduced into national immunization programs. In 2006, 51 lower and lower middle income countries reported spending a mean US$12 per surviving infant on routine immunization. By 2012, the figure had risen to $20, a 67% increase. This study tests the hypothesis that lower and lower middle income countries will spend more on their routine immunization programs as their economies grow. A panel data regression approach is used. Expenditures reported by governments annually (2006-12) through the World Health Organization/UNICEF Joint Reporting Form are regressed on lagged annual per capita gross national income (GNI), controlling for prevailing mortality levels, immunization program performance, corruption control efforts, geographical region and correct reporting. Results show the expenditures increased with GNI. Expressed as an elasticity, the countries spent approximately $6.32 on immunization for every $100 in GNI increase from 2006 to 2012. Projecting forward and assuming continued annual GNI growth rates of 10.65%, countries could be spending $60 per infant by 2020 if national investment functions increase 4-fold. Given the political will, this result implies countries could fully finance their routine immunization programs without cutting funding for other programs.

Development of a cholera vaccination policy on the Island of Hispaniola, 2010-2013

Deployment of oral cholera vaccine (OCV) on the Island of Hispaniola has been considered since the emergence of the disease in October of 2010. At that time, emergency response focused on the time-tested measures of treatment to prevent deaths and sanitation to diminish transmission. Use of the limited amount of vaccine available in the global market was recommended for demonstration activities, which were carried out in 2012. As transmission continues, vaccination was recommended in Haiti as one component of a comprehensive initiative supported by an international coalition to eliminate cholera on the Island of Hispaniola. Leveraging its delivery to strengthen other cholera prevention measures and immunization services, a phased OCV introduction is pursued in accordance with global vaccine supply. Not mutually exclusive or sequential deployment options include routine immunization for children over the age of 1 year and campaigns in vulnerable metropolitan areas or rural areas with limited access to health services.

Progress with rotavirus vaccines: summary of the Tenth International Rotavirus Symposium

Over 350 scientific, public and private sector experts from 47 countries convened at the Tenth International Rotavirus Symposium in Bangkok, Thailand on 19-21 September 2012 to discuss progress in the prevention and control of rotavirus, the leading cause of diarrhea hospitalizations and deaths among young children worldwide. Participants discussed data on the burden and epidemiology of rotavirus disease, results of trials of rotavirus vaccines, postmarketing data on vaccine impact and safety from countries that have implemented rotavirus vaccination programs, new insights in rotavirus pathogenesis, immunity and strain diversity, and key issues related to vaccine policy and introduction.

Angiotensin II-induced JNK activation is mediated by NAD(P)H oxidase in isolated rat pancreatic islets

Angiotensin II (AII), the active component of the renin angiotensin system (RAS), plays a vital role in the regulation of physiological processes of the cardiovascular system, but also has autocrine and paracrine actions in various tissues and organs. Many studies have shown the existence of RAS in the pancreas of humans and rodents. The aim of this study was to evaluate potential signaling pathways mediated by AII in isolated pancreatic islets of rats. Phosphorylation of MAPKs (ERK1/2, JNK and p38MAPK), and the interaction between proteins JAK/STAT were evaluated. AII increased JAK2/STAT1 (42%) and JAK2/STAT3 (100%) interaction without altering the total content of JAK2. Analyzing the activation of MAPKs (ERK1/2, JNK and p38MAPK) in isolated pancreatic islets from rats we observed that AII rapidly (3 min) promoted a significant increase in the phosphorylation degree of these proteins after incubation with the hormone. Curiously JNK protein phosphorylation was inhibited by DPI, suggesting the involvement of NAD(P)H oxidase in the activation of protein.

Creating sustainable financing and support for immunization programs in fifteen developing countries

Immunization programs are important tools for reducing child mortality, and they need to be in place for each new generation. However, most national immunization programs in developing countries are financially and organizationally weak, in part because they depend heavily on funding from foreign sources. Through its Sustainable Immunization Financing Program, launched in 2007, the Sabin Vaccine Institute is working with fifteen African and Asian countries to establish stable internal funding for their immunization programs. The Sabin program advocates strengthening immunization programs through budget reforms, decentralization, and legislation. Six of the fifteen countries have increased their national immunization budgets, and nine are preparing legislation to finance immunization sustainably. Lessons from this work with immunization programs may be applicable in other countries as well as to other health programs.

The future of immunisation policy, implementation, and financing

Vaccines have already saved many lives and they have the potential to save many more as increasingly elaborate technologies deliver new and effective vaccines against both infectious diseases--for which there are currently no effective licensed vaccines--such as malaria, tuberculosis, and HIV and non-infectious diseases such as hypertension and diabetes. However, these new vaccines are likely to be more complex and expensive than those that have been used so effectively in the past, and they could have a multifaceted effect on the disease that they are designed to prevent, as has already been seen with pneumococcal conjugate vaccines. Deciding which new vaccines a country should invest in requires not only sound advice from international organisations such as WHO but also a well informed national immunisation advisory committee with access to appropriate data for local disease burden. Introduction of vaccines might need modification of immunisation schedules and delivery procedures. Novel methods are needed to finance the increasing number of new vaccines that have the potential to save lives in countries that are too poor to afford them. Here, we discuss some options.

New vaccines for developing countries: will it be feast or famine?

The Revolving Fund of the Pan American Health Organization (PAHO) has an almost 30 year track record of providing access to essential vaccines for the entire population of Latin America and the Caribbean region. The activities of the PAHO Revolving Fund, coupled with the provision of high-quality technical assistance, were crucial to the successful control, elimination, or eradication of most of the region's great childhood killers, including measles and polio. Today, however, the Revolving Fund faces new challenges in the form of procuring a new generation of vaccines for human papillomavirus infection, rotavirus, and pneumococcal disease, which are priced orders of magnitude higher than the traditional childhood vaccines. The high cost of these essential new vaccines may require the PAHO Revolving Fund to establish innovative financial mechanisms for procuring these products at prices affordable for national immunization programs in Latin America and the Caribbean. The alternative, namely to bypass the Revolving Fund, could severely threaten the health of the region, especially Latin America's poorest people.

Recommendations for cervical cancer prevention in Latin America and the Caribbean

Cervical cancer control in the Latin America and Caribbean (LAC) region has been, and remains, a priority and a major public health challenge. It also provides the opportunity for the advancement of research into novel cervical cancer preventative tools including the use of prophylactic human papillomavirus (HPV) vaccines, HPV-based screening options and low technology visual inspection methods. The challenges for prevention are compounded because cervical cancer cases continue to cluster in the low socio-economic and rural populations, thus requiring strong political and social commitments to ensure effective implementation in the region. Although cytology-based screening activities exist in the majority of LAC countries, these have been largely based on opportunistic screening services. Evaluation of the impact of screening is often focused on assessing coverage of the population with Pap smears. However, regardless of the chosen technology a screening program requires a complex set of activities that must also be of high quality such us ensuring access of the underserved populations to the program, maintaining routine quality controls of the screening procedures and organizing the proper follow-up of women with abnormal screening results. The cost of the HPV vaccine and of the delivery infrastructure required is currently a significant obstacle for widespread introduction that will require collaborative resolve between public health organizations, governments and vaccine manufacturers. It is important to ensure that HPV vaccines are made available to the wider public, not only to those who can afford it. This monograph and the associated regional reports have carefully identified and discussed the many challenges and opportunities to be considered for policy decisions, in particular the complex interplay between vaccination strategies and subsequent screening requirements. An advanced cost-benefit analysis, using models calibrated to specific countries in the region, presents the range of options and relative costs thus providing evidence-based scientific guidance to governments and providers in the context of a significant and systematic international review effort.

Progress in vaccination against Haemophilus influenzae type b in the Americas

The authors review the progress to date in Hib vaccine introduction, the lessons learned, and the remaining challenges.

The Measles Laboratory Network in the region of the Americas

The success of measles eradication depends upon a laboratory network to rapidly analyze samples obtained as part of surveillance and case investigation. The Pan American Measles Laboratory Network was established in 1995. Major activities of the 22 participating laboratories include the rapid testing of serum samples to diagnose measles, analysis and recommendation of techniques to be used in serologic testing, training in virus isolation, and procurement and distribution of laboratory materials. In addition, a comprehensive quality-control program and an electronic communication network have been developed. Testing for rubella has also been incorporated. The Network has been crucial to the great progress made toward eradicating measles from the Western Hemisphere. The priority given to the laboratories in the Network must continue in order to ensure that the eradication goal is reached and that validation of the interruption of endemic transmission of measles is documented.

[The use of chest X-rays for surveillance of bacterial pneumonias in children in Latin America]

The Division of Vaccines and Immunization of the Pan American Health Organization (PAHO) is promoting epidemiological surveillance of bacterial pneumonias in children in Latin America in order to generate scientific evidence to support future decisions concerning using vaccines to control such pneumonias in the countries of the Region of the Americas. The diagnosis of these diseases rarely includes bacteriological documentation of the causative agent. Therefore, studies of this type that are carried out around the world accept radiological images of alveolar consolidation as a confirmatory criterion for a presumptively bacterial pneumonia. This piece examines the theoretical rationale and requirements for using thorax radiology as an instrument for epidemiological surveillance of bacterial pneumonias. The piece also summarizes the activities carried out during 2 years of joint efforts between the Center for Vaccine Development (Centro para Vacunas en Desarrollo) of Chile and PAHO's Division of Vaccines and Immunization. During those 2 years, the two groups encouraged the epidemiological study of bacterial pneumonias in Latin American children, using internationally accepted criteria and definitions as well as tools and practical solutions adapted to the reality of the Region of the America. The activities carried out so far show both the need for and the feasibility of standardizing the interpretation of chest radiographs so that they can be used in epidemiological studies.

Cost-effectiveness of measles elimination in Latin America and the Caribbean: a prospective analysis

BACKGROUND

In 1994, the Americas set a goal of interrupting indigenous measles transmission from the Western Hemisphere by 2000. To accomplish this goal, the Pan American Health Organization (PAHO) developed an enhanced measles vaccination strategy.

METHODS

Cost data was collected at PAHO for Latin American and Caribbean (LAC) countries covering 96% of the region's population on components of the routine programs, and the 'follow-up' activities from member countries. In order to interpret our findings we have compared the present scenario regarding measles with one that would have ensued if past trends continued.

RESULTS

For the entire LAC population, estimated cost of elimination program will be US$ 571 million in present value terms.

INTERPRETATION

The vaccination strategy toward achieving elimination of measles costs USD 244 million, incremental from the cost of vaccination before the elimination program. Within 2000-2020, the current program will have prevented the occurrence of 3.2 million cases of measles and 16,000 deaths. Thus, vaccination strategy prevents a single case of measles at the cost of USD 71.75 and prevents a death due to measles at the cost of USD 15,000. The case fatality rate depends on a well functioning treatment program for measles cases. The vaccination strategy saves a total of USD 208 million in treatments costs due to reduced incidence of measles.

Outbreak of poliomyelitis in Hispaniola associated with circulating type 1 vaccine-derived poliovirus

An outbreak of paralytic poliomyelitis occurred in the Dominican Republic (13 confirmed cases) and Haiti (8 confirmed cases, including 2 fatal cases) during 2000-2001. All but one of the patients were either unvaccinated or incompletely vaccinated children, and cases occurred in communities with very low (7 to 40%) rates of coverage with oral poliovirus vaccine (OPV). The outbreak was associated with the circulation of a derivative of the type 1 OPV strain, probably originating from a single OPV dose given in 1998-1999. The vaccine-derived poliovirus associated with the outbreak had biological properties indistinguishable from those of wild poliovirus.