GLOBAL TB IMPACT MEASUREMENT

Transcription

1 GLOBAL TB IMPACT MEASUREMENT What is it? Why is it important? How can it be done? What will it cost? 1. What is global TB impact measurement and why is it important? Global TB Impact Measurement is the evaluation of whether the epidemiological burden of TB (measured as cases and deaths) is being reduced in line with global targets for TB control. It has assumed unprecedented importance because, starting around the year 2000, there has been a fundamental shift in the environment in which TB control is being funded, delivered and evaluated. Between 2000 and 2004, global targets for TB control were extended to include impact targets (reductions in cases and deaths), in addition to the "outcome targets" (to detect 70% of smear-positive TB cases and to cure 85% of detected cases in DOTS programmes) first set by the WHO's World Health Assembly (WHA) in These impact targets have been set within the UN's Millennium Development Goals (MDGs), by the Stop TB Partnership and as part of the Stop TB Strategy launched by WHO in MDG 6 target 6.C is to halt and reverse incidence by 2015 at global level. The Stop TB Partnership has adopted this target and in addition has set targets to halve global prevalence and death rates by 2015, compared to a baseline of The Stop TB Strategy explicitly added "impact measurement" to the regular monitoring of case-finding and treatment outcomes that had previously been emphasized in the DOTS strategy. The WHO's WHA recognised all of these targets in a resolution passed in 2007 (WHA 60.19; see Annex 1). During the same period, financial investments in TB control have substantially increased and a range of new initiatives and approaches have been introduced. Governments of TB endemic countries as well as their technical and financial partners are increasingly required to account for public funds within a "results-based" framework, which in turn has led to much greater demand for health information. The Global Fund is among the more prominent examples of this trend. 1 To respond to the necessity of producing evidence of impact and value-for-money, many countries are seeking technical assistance from WHO and other agencies. In combination, these factors mean that impact measurement should be a top priority for all countries, technical agencies and financial partners committed to the achievement of global targets for TB control. 1 For example, the Global Fund has funded a "five-year Impact Evaluation" in 20 countries 5 years into the grant cycle of these countries. More recently, internationally agreed Monitoring & Evaluation indicators are being used in grant agreements (see The Global Fund M & E Toolkit - Concept Note - 3 rd edition, 2008).

2 2. The WHO Global Task Force on TB Impact Measurement Based on WHA (see Annex 1), WHO is required by its member states to report on whether the 2015 global targets for TB control are achieved, to report on progress in the interim, and to help to strengthen health information systems. The Global Task Force on TB Impact Measurement (hereafter the Task Force) was established by WHO in June The Task Force's mandate is to produce a robust, rigorous and widely endorsed assessment of whether the 2015 targets set for TB control are achieved at global level and for each WHO region, to regularly report on progress towards these targets in the years leading up to 2015, and to strengthen national capacity in monitoring and evaluation of TB control. The Task Force includes experts in TB epidemiology, representatives from major technical and financial partners, and representatives from countries with a high burden of TB. Following two Task Force meetings (June 2006; December 2007), the Task Force has defined and reached consensus on three major and inter-related areas of work which will need to be implemented to achieve the Task Force's goal. These are: 1. Strengthening of routine surveillance systems including certification. Surveillance data will be essential for measuring incidence, prevalence and mortality in all countries, and in the European Region and the Region of the Americas particular emphasis will be given to the certification 2 of national surveillance systems. 2. Disease prevalence surveys. Surveys of the prevalence of disease have been identified by the Task Force as necessary in 21 priority countries, mainly in Asia and Africa. 3. Analytical methods. Periodic review of analytical methods that are used to translate data from surveillance systems and surveys into estimates of incidence, prevalence and mortality is essential, as is revision of these methods when appropriate (e.g. substantially better data become available, a clearly better analytical method is identified). Each of these three areas of work is based on a Task Force review of the methods available to measure the epidemiological burden of TB and the impact of control efforts, which was published in Lancet Infectious Diseases in January Strategic Pathways 3.1 Strengthening of routine surveillance systems including certification of TB surveillance systems The ultimate goal for all countries is to be able to use routine surveillance data (of TB cases and deaths) to measure incidence, prevalence and mortality. In the period up to 2015, this is most feasible in the European Region and in the Region of the Americas, as well as parts of the Eastern Mediterranean. The Task Force will give particular emphasis to the "certification" of surveillance systems in these regions, with certification meaning that notifications are assessed to equate to, or be a close proxy 2 See next subsection for definition. 3 Dye C et al. Measuring tuberculosis burden, trends, and the impact of control programmes. Lancet Infectious Disease 2008 Jan 15.

3 for, incidence. Routine surveillance data will also be used to assess incidence, prevalence and mortality rates in other countries, but it is unlikely that "certification" will be feasible. To achieve "certified" status in these countries, the quality and coverage of existing surveillance systems will need to be considerably improved. The certification process will be developed by the Task Force and other experts who will participate in this first area of work. The process will define standard procedures for assessing the quality of a surveillance system (including operational research studies where appropriate), and the extent to which it captures comprehensive and high-quality, reliable data; and the standard benchmarks or "tests" to be used to determine whether or not a country's surveillance system can be "certified". These standard procedures and benchmarks/tests will be developed using lessons learned from studies that have already been undertaken (e.g. in Italy), experience within strong TB surveillance systems (e.g. the Netherlands), and assessment missions and expert consultations, and will be peer-reviewed. Once standard methods have been developed, countries will be invited to apply for certified status and assessments to determine whether or not they meet the criteria will be undertaken (likely by Task Force members as well as experts from outside the Task Force). The standard procedures for assessing the quality of a surveillance system will also be relevant to countries not applying for certified status, as they can be used to produce new and more accurate assessments of what fraction of incident cases are being notified (which in turn will allow incidence to be better estimated from notification data). 3.2 Implementation of disease prevalence surveys While the Task Force has agreed that the ultimate aim for all countries is to be able to rely on data on TB cases and deaths collected through routine surveillance and vital registration systems to measure the implementation and impact of TB control, it has also recognized that in the interim special population surveys of the prevalence of disease will be needed in many countries. This is particularly the case for countries in the African, South East Asia and Western Pacific regions. These surveys are required to produce better estimates of the number of prevalent cases of TB in countries where routine surveillance data cannot be relied upon. New data from prevalence surveys may also help to refine estimates of incidence and death rates (see also area of work 3). The December 2007 meeting of the Task Force focused on where prevalence of disease surveys need to be undertaken to measure global and regional progress towards the 2015 targets, as well as the methods to be applied in implementing such surveys. Based on an agreed set of epidemiological and other criteria, 4 21 countries were identified as top priorities for the implementation of prevalence of disease surveys (these are listed in Table 1, page 7). A further 36 countries met the basic criteria for conducting a prevalence survey, but do not need to conduct surveys for the purposes of assessment of the burden of TB or the impact of control at global and regional level. 5 Since assessment of the impact of TB control requires that the measurement of TB cases is carried out on (at least) two separate occasions, some of 4 See background paper for Task Force meeting, and the meeting report. 5 For example, the African countries that met the criteria accounted for more than 90% of the region's cases; from a global and regional perspective it is not necessary to achieve such high regional coverage of expensive and logistically challenging surveys.

4 the 21 priority countries that do not any survey data later than 1990 will need to conduct two prevalence of disease surveys before The WHO guidelines for disease prevalence surveys were universally endorsed by the Task Force. The 21 priority countries will be given particular attention and support by the Task Force. For example, the Task Force's technical partners will provide training for survey principal and co-investigators, and will ensure that each country is matched to one or more technical partners to ensure that the necessary level of technical assistance is provided (Table 2b shows existing technical support available to countries; recent experience from Asia shows that frequent visits are necessary to provide an appropriate level of technical assistance). The first two of a series of training workshops are being organized by WHO in Geneva in March and June 2008, with co-sponsorship from the World Bank and with the participation and technical support of CDC and KNCV. These 2 workshops will provide training to country teams of 2 3 people from 9 African countries and Pakistan. In general, countries are being advised to seek financial support from the Global Fund to cover the in-country costs of surveys. Depending on the estimates of TB prevalence which are the basis of sample size calculations, the costs of each survey are expected to vary from US$ 1-2 million each, excluding technical assistance. During training workshops, countries will be helped to develop grant applications and/or to reprogramme existing grants. Funding for technical assistance is likely to be required from separate funding mechanisms. 3.3 Review/updating of methods used to produce country-specific estimates of incidence, prevalence and mortality WHO has produced estimates of key indicators of the epidemiological burden of TB for every country in the world - incidence, prevalence and mortality, and their trends through time - since These have been published in peer-reviewed journals and in the series of annual WHO reports on global tuberculosis control. The existing estimates are based on data and methods that have known limitations. Periodic review of the estimates and the methods used to obtain the estimates is needed to overcome these limitations, to produce the best possible appraisal of the state of the global epidemic, and to maintain a consensus around published and widely-used figures. Ten years on from the original development of methods to produce estimates of the epidemiological burden of TB, and in the context of the new Global Burden of Disease (GBD) project (due to publish estimates for 1990 and 2005 in a book scheduled for launch in 2010) as well as the wider work on measuring the global burden of TB and the impact of TB control efforts with which the Task Force is concerned, it is important to periodically review, and update or improve where possible, the existing data and methods. These methods will include how to make use of new data from prevalence surveys (Area 2) as well as new assessments of routine surveillance systems (Area 1). A full proposal describing this area of work, produced jointly by KNCV and WHO, is already available. 4. Organization of Task Force work The Task Force is hosted, convened, and managed by WHO HQ, Geneva. Three groups have been established to cover each of the three areas of work defined above,

5 based on Task Force members areas of interest and expertise. In some cases, Task Force members have nominated other experts from their respective agencies to participate in one or more of the three areas of work. Other experts will also be invited to participate in Task Force work on an ad-hoc basis, as appropriate. Each of the three groups has been assigned a leader/coordinator, who is ultimately responsible for ensuring that the each group fulfills the mandate that the Task Force has assigned to it (there are two co-leaders in the case of Area 3). A second person will be identified by WHO to serve as the secretariat of each group. Each group will be requested to regularly report back to the full Task Force (at least once but often twice per year). International and national technical partners will be mapped to support in-country work related to prevalence surveys, assessment of surveillance systems, and analytical methods. Dr Jaap Broekmans, former Executive Director of KNCV Tuberculosis Foundation in the Netherlands, and former Chair of the WHO Strategic and Technical Advisory Group on TB (STAG-TB), is the Chair of the Task Force. For the Task Force to successfully implement its mandate, it is essential that all partner institutions are fully committed. These include the Global Fund, the World Bank, bilateral donors, national and international technical agencies, and of course the countries themselves. There is already strong evidence of country commitment to implementing disease prevalence surveys, and both the World Bank and the Global Fund provided a strong endorsement of the Task Force's work at December 2007 Task Force meeting. 5. Task Force Membership TB Endemic countries: Representatives from countries with a high burden of TB. Task Force meetings to date have included representatives from India, Indonesia, Malawi, Nigeria, the Philippines, South Africa, and Tanzania. Technical agencies with expertise in TB epidemiology: CDC (Centers for Disease Control, Atlanta, USA); ECDC (European Centre for Disease Control, Stockholm); KNCV Tuberculosis Foundation (The Hague, the Netherlands); RIT (Research Institute for Tuberculosis, Kanagawa, Japan); the Union (International Union against TB and Lung Disease, Paris, France); WHO (HQ and Regional Offices); Financial agencies: The Global Fund (Geneva, Switzerland); USAID (United States Agency for International Development, Washington, USA); the World Bank (Washington, USA). 6. Budget Funds are necessary to cover the costs of coordination activities, technical assistance and a contingency budget for the implementation bottlenecks of the prevalence surveys. The budget is presented in Table 1; it is estimated that between US$ 11 and 12 million will be needed. The costs of the implementation of the prevalence surveys per se have not been included in this total.

6 Table 1. Budget Units Unit cost Total cost 1) Technical coordination and support by WHO meeting (full task force) , ,000 meeting (3 sub-groups) , ,000 secretariat for 3 groups 330, , ,000 1,000,000 technical staff, incl expert consultants 1,000,0001,000,0001,000,000 3,000,000 2) Strengthening surveillance country visits ,500 75,000 3) Prevalence surveys joint workshops , ,000 country visits ,000 5,250,000 Strategic implementation support , ,000 4) Analytical methods country visits , ,000 Total 3,915,0003,855,0003,805,000 11,585, Dissemination of Results Several high-profile, high-quality, and in-demand products will be produced and published, either as official WHO publications and/or in peer-reviewed journals. These include: 1. A final set of estimates of incidence, prevalence and deaths in 2015 and assessment of whether or not the 2015 targets were met globally and for the six WHO regions, supported by documentation of accompanying data/methods 2. In-depth evaluations of the impact of TB control efforts in selected countries 3. Publication of annual updates on progress towards the 2015 targets in the annual series of WHO reports on Global Tuberculosis Control (2009 report onwards) 4. Methodological papers related to analytical methods and certification of surveillance systems 5. WHO Policy paper on Impact Measurement (2008) 6. Estimates of global mortality due to TB for the Global Burden of Disease project (to be published in 2010).

7 Annex 1. Extracts from World Health Assembly Resolution WHA60.19, passed in 2007 The WHA urges all Member States: " (b) accelerating improvement of health-information systems, both in general and for tuberculosis in particular, in order to serve the assessment of national programme performance;" 1. The WHA requests the Director-General: " (5) to strengthen mechanisms to review and monitor estimates of impact of control activities on the tuberculosis burden, including incidence, prevalence and mortality with specific attention to vulnerable groups highly at risk, such as poor people, migrants and ethnic minorities; (8) to report to the Sixty-third World Health Assembly through the Executive Board on : (b) progress made in achieving the international targets for tuberculosis control by 2015, using the "proportion of tuberculosis cases detected and cured under DOTS" (Millennium Development Goal indicator 24) as a measure of the performance of national programmes, and tuberculosis incidence and "prevalence and death rates associated with tuberculosis" (Millennium Development Goal indicator 23) as a measure of the impact of control on the tuberculosis epidemic."

8 Annex 2 Priority list of countries for carrying out TB disease prevalence surveys, as agreed by the December 2007 Task Force on TB Impact Measurement. Region Country High burden Estimated TB Prevalence SS+* AFR high HIV prevalence Kenya yes AFR high HIV prevalence Malawi no AFR high HIV prevalence Mozambique yes AFR high HIV prevalence Nigeria yes AFR high HIV prevalence South Africa yes AFR high HIV prevalence Uganda yes AFR high HIV prevalence UR Tanzania yes AFR high HIV prevalence Zambia no AFR low HIV prevalence Ghana no AFR low HIV prevalence Mali no AFR low HIV prevalence Rwanda no AFR low HIV prevalence Sierra Leone no EMR Pakistan yes SEA Bangladesh yes SEA Indonesia yes SEA Myanmar yes 75.6 SEA Thailand yes 84.4 WPR Cambodia yes WPR China yes 89.4 WPR Philippines yes WPR Viet Nam yes 89.5 * per 100,000 individuals

9 Annex 3 Ongoing national prevalence surveys and supporting technical agencies Bangladesh KNCV, Damien Foundation Cambodia RIT/JATA, JICA (donor) and WHO China Damien Foundation, WHO, IUATLD, Chinese Government Myanmar PSI (Population Service Institute), JICA (donor), WHO and RIT/JATA Philippines TDF (Tropical Disease Foundation), KIT (Korean Institute for TB), US- CDC, RIT/JATA (not officially) Thailand Vietnam No formal technical support KNCV Tuberculosis Foundation, RIT/JATA, WHO Upcoming national prevalence surveys that have already identified supporting technical agencies Kenya Malawi Mali Nigeria Rwanda Tanzania Uganda Zambia Pakistan KNCV Tuberculosis Foundation KEMRI (Kenya Medical Research Institute) Liverpool School of Tropical Medicine National College of Medicine REACH (Research on Equity and Community Health - Malawi) KNCV Tuberculosis Foundation US-CDC Damien Foundation INS (Institut National des statistiques) Université Nationale du Rwanda - École de Sante Publique NIMR (National Institute for Medical Research) MUCHS (Muhimbily University College of Health Sciences) KNCV Tuberculosis Foundation Institute of Tropical Medicine, Antwerp, Belgium Kampala University ZAMBART (Zambia AIDS Related TB Research Team) WHO, the Union (to be confirmed)