Print version ISSN 0042-9686
Bull World Health Organ vol.85 n.5 Genebra May. 2007
Léopold Blanc1; Lindsay Martinez
Stop TB Department, World Health Organization, 20 avenue Appia, 1211 Geneva 27, Switzerland
Tuberculosis (TB) is one of the major causes of illness and death in many countries and a significant public health problem worldwide. Its importance as a barrier to socioeconomic development is recognized in the Millennium Development Goals, and combating TB is seen as an integral part of poverty reduction programmes. International targets for TB control set for 2005 enhanced global commitment to achieve substantial advances in reducing the burden of morbidity and mortality due to TB. These targets, approved by the World Health Assembly in 1991, called for a 70% case detection rate, with successful treatment of 85% of the detected cases. Based on the epidemiology of TB at the time, they were considered realistic and achievable.
A concerted international effort and considerable resources have been invested to achieve these targets, meriting careful evaluation so that maximal benefit from the experience will accrue for TB control and for other public health programmes. This issue of the Bulletin marks a milestone in global efforts to control TB and provides a forum for review and debate on how the targets were pursued, how progress was assessed and conclusions were reached, and what lessons can be learnt from the process. These questions are examined from global, regional and national perspectives.
Were the targets reached? Dye et al. (364369) answer "yes and no". Based on the global average, they were missed but only narrowly, with a case detection rate of 60% and cure rate of 84%; and one or both targets were achieved by 119 countries. These results represent enormous overall progress, although with marked regional and national disparities.
But were the data reliable? Van der Werf & Borgdorf (370376) point out that inadequate information on the TB burden in many countries means uncertainty about TB incidence and therefore about case detection rates, limitations which Dye et al. acknowledge. With only 27 of 211 countries considered to have good information systems, including none of the 22 high-burden countries, strengthening in this area is urgently needed, particularly in Africa.
How were the successes achieved? The WHO Western Pacific Region met both targets, the only region to do so, as described by van Maaren et al. (360-363). Key factors were strong WHO leadership, government commitment, effective partnerships and a committed front-line work force, giving priority to the Regions seven high-burden countries.
National plans and development of partnerships are the two pillars of the Global DOTS Expansion Plan for high-burden countries, as explained by Enarson & Billo (395398), who introduce a discussion highlighting several constructive country initiatives. The Global Drug Facility, described by Matiru et al. (348353), has greatly improved access to quality-assured, preferentially priced anti-TB drugs and provides a model for other programmes.
What does TB control cost? Until a global system for financial monitoring was established in 2002, information on this crucial issue was fragmentary and imprecise. Floyd et al. (334340) show that an effective system can be set up to provide information on funding needs and gaps, utilization of mobilized funds and impact on the TB burden.
What were the special challenges? The epidemiology of TB has changed profoundly since the targets were set, greatly complicating the task and stretching scarce resources. The discussions introduced by Laserson (377-381) and Blöndal (387390), respectively, consider the aggravation of the TB epidemic by HIV infection and the increasing threat of multidrug-resistant TB (MDR-TB), exemplified in several country commentaries. Rays of hope come from Malawi, where Chimzizi & Harries (385386) report that the management of TB and HIV has improved dramatically; and from Latvia, where Leimane (393394) reports that intensive efforts have reduced the incidence of MDR-TB in recent years. Complex emergencies in many countries have disrupted disease control activities and required innovative strategies for TB control, as will be discussed by Coninx in a subsequent issue of the Bulletin.
Among the longstanding difficulties facing TB control efforts, inadequacy of laboratory services stands out, particularly in Africa where most countries lack capacity to confirm diagnosis, monitor treatment and determine drug sensitivity. Ridderhof et al. (354359) provide ample evidence that TB targets will not be met without urgent measures to remedy the present deficiencies. Successful TB control is also heavily dependent on effective treatment of patients, requiring adherence throughout the full course of medication. Different approaches to promoting adherence are discussed by Frieden & Sbarbaro (407409) and by Garner et al. (404406).
What does the future hold? Maher et al. (341346) discuss the Global Plan to Stop TB, 20062015, and its relevance for other health issues; and Brosch & Vincent (410412) outline the potential opportunities offered by science. While looking ahead, the public health classic by Mahler (413417) reminds us that we build upon concepts that owe much to his vision of four decades ago.