Mortality due to tuberculosis (per 100 000 population)
Rationale for use
Prevalence and mortality are direct indicators of the burden of tuberculosis (TB), indicating the number of people suffering from the disease at a given point in time, and the number dying each year. Furthermore, prevalence and mortality respond quickly to improvements in control, as timely and effective treatment reduce the average duration of disease (thus decreasing prevalence) and the likelihood of dying from the disease (thus reducing disease-specific mortality).
Millennium Development Goal 6 is "to combat HIV/AIDS, malaria and other diseases" [including TB]. This goal is linked to Target 8—"to have halted by 2015 and begun to reverse the incidence of malaria and other major diseases"—and indicator 24—"prevalence and mortality rates associated with TB". The Stop TB Partnership has endorsed the related targets of reducing per-capita prevalence and mortality of TB by 50% relative to 1990, by the year 2015. There are few good data with which to establish prevalence of and mortality attributable to TB, particularly for the baseline year of 1990. However, current best estimates suggest that implementation of the Global Plan to Stop TB 2006–2015 will halve 1990 prevalence and mortality rates globally, and in most regions by 2015, although not in Africa or eastern Europe.
Definition
The estimated number of deaths attributable to TB in a given time period. Expressed in this database as deaths per 100 000 population per year. Includes deaths from all forms of TB, and deaths from TB in people with HIV.
Associated terms
All forms: pulmonary (smear-positive and smear-negative) and extrapulmonary TB.
Data sources
Vital registration data where available (few countries with high burdens of TB have complete vital registration systems with good coverage). Elsewhere, mortality is estimated from incidence.
Methods of estimation
Estimates of TB incidence, prevalence and mortality are based on a consultative and analytical process in WHO and are published annually (see WHO, 2006c)
The methods used to estimate rates of mortality from TB are described in detail elsewhere (Dye C et al., 1999; Corbett EL et al., 2003; WHO, 2006c).
Country-specific estimates of TB mortality are, in most instances, derived from estimates of incidence (see Incidence of tuberculosis) combined with assumptions about the case fatality rate. The case fatality rate is assumed to vary according to whether the disease is smear-positive or not; whether the individual receives treatment in a directly-observed treatment, short-course (DOTS) programme or non-DOTS programmes, or is not treated at all; and whether the individual is infected with HIV.
Disaggregation
Estimates are routinely disaggregated into smear-positive and other forms of disease, and by HIV status (in adults aged 15–49 years).
References
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http://archinte.ama-assn.org/cgi/content/abstract/163/9/1009
Corbett EL et al. The growing burden of tuberculosis: global trends and interactions with the HIV epidemic. Archives of Internal Medicine, 2003, 163:1009–1021. -
http://jama.ama-assn.org/cgi/content/abstract/282/7/677
Dye C et al. Global burden of tuberculosis: estimated incidence, prevalence and mortality by country. Journal of the American Medical Association, 1999, 282:677–686. -
http://www.stoptb.org/globalplan/
WHO. The Global Plan to Stop TB, 2006–2015. Geneva, World Health Organization, 2006a (WHO/HTM/STB/2006.35). -
http://www.who.int/tb/publications/2006/stop_tb_strategy.pdf
WHO. The Stop TB Strategy: building on and enhancing DOTS to meet the TB-related Millennium Development Goals. Geneva, World Health Organization, 2006b (WHO/HTM/STB/2006.37). -
http://www.who.int/tb/publications/global_report/en/
WHO. Global tuberculosis control: surveillance, planning, financing. WHO report 2006. Geneva, World Health Organization, 2006c (WHO/HTM/TB/2006.362).
Database
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http://www.who.int/tb/country/global_tb_database
Global TB database, WHO -
http://unstats.un.org/unsd/mi/mi_goals.asp
United Nations Millennium Development Goals Indicator database
Comments
Mortality attributable to TB can be measured directly only where there is a good vital registration system, with accurate coding of cause-of-death. The number of patients dying while receiving treatment for TB (as reported in routine follow-up of cohorts of TB patients) is not an true indication of mortality attributable to TB, as it includes deaths from causes other than TB, and excludes deaths from TB among people not on treatment.
Mortality surveys and demographic surveillance systems using verbal autopsy to determine cause of death are a potential source of improved estimates of mortality attributable to TB.