|Tuberculosis in the Americas: Regional Report 2009|
The regional report on tuberculosis (TB) control, published by the Pan American Health Organization, provides an updated assessment of the TB epidemic and the progress made to date in terms of its control in the region and the countries, within the framework of the goals set for 2015. The results are mainly based on data reported to WHO in 2008 through TB data collection forms, as well as on the data collected yearly from 1996 to 2007.
Introduction: The goals for global tuberculosis control have been set within the Framework of the Millennium Development Goals (MDGs). Target 8, included in MDG 6, consists of having halted and begun to reduce incidence by 2015. The Stop TB Partnership has set another two targets related to impact, which are to reduce the prevalence and mortality rates by half, with respect to the 1990 levels, by 2015. The goals related to results set by the World Health Assembly in 1991 are to detect at least 70% of all new smear-positive cases in DOTS programs and to satisfactorily treat at least 85% of them. The five targets were adopted by the Stop TB Partnership and were recognized in a World Health Assembly Resolution (WHA60.19) in 2007.
Stop TB Strategy: The Stop TB Strategy, launched by WHO in 2006, is designed to reach the impact targets by 2015, as well as those related to case detection and therapeutic success. The Global Plan, launched in January 2006, details the scale with which to implement the six main components of the Stop TB Strategy:
All six components are aimed at reaching the MDG targets, as well as obtaining the necessary funding, for each successive year from 2006 to 2015.
The Pan American Health Organization has formulated the Regional Plan for Tuberculosis, 2006–2015, based on the Stop TB Strategy and adapting it to the peculiarities of the region of the Americas, among which are the following emerge as major issues:
Summary of the Regional Plan for TB Control, 2006–2015
Source: PAHO/WHO, Regional Plan for Tuberculosis, 2006–2015.
Scenarios for the Implementation of the Regional Plan
Due to the great heterogeneity of the epidemiological situation of TB in the different countries of the Americas, the Regional Plan for Tuberculosis, 2006–2015 has been stratified—in order to better analyze and intervene in the countries of the region, and in accordance with operational and epidemiological criteria—into four scenarios (two of which are subdivided). These criteria are WHO estimated TB incidence and DOTS coverage as reported by the countries in 2003. Thus, the interventions are relatively similar for all the countries making up the scenario.
The parameters taken into account for defining the scenarios were:
· Scenario 1: Countries with an estimated TB incidence of less than 25 cases per 100,000 inhabitants and DOTS coverage greater than 90%. For greater precision, it has been subdivided into:
- Scenario 1A: Countries with an estimated TB incidence of less than 12.5 cases per 100,000 inhabitants and DOTS coverage greater than 90%.
- Scenario 1B: Countries with an estimated TB incidence greater than or equal to 12.5 and less than 25 per 100,000 and DOTS coverage greater than 90%.
· Scenario 2: Countries with an estimated TB incidence between 25 and 50 cases per 100,000 inhabitants and DOTS coverage greater than 90%.
· Scenario 3: Countries with an estimated TB incidence greater than 50 cases per 100,000 inhabitants and DOTS coverage greater than 90%.
· Scenario 4: Countries with an estimated TB incidence greater than 50 cases per 100,000 inhabitants and DOTS coverage less than 75%. Subdivided into:
- Scenario 4A: Countries with an estimated TB incidence greater than 50 and less than 80 cases per 100,000 inhabitants and DOTS coverage less than 75%.
- Scenario 4B: Countries with an estimated TB incidence of 80 cases or more per 100,000 inhabitants and DOTS coverage less than 75%.
1. The Americas’ contribution to the global TB burden is only 3.2% of all forms of TB. However, and according to estimates, the Americas ranks second among the world’s regions in having the greatest proportion of new cases of TB/HIV co-infection and deaths as a result of TB/HIV.
2. Tuberculosis continues to represent an important cause of illness, death, and great economic cost in the Americas. In 2007, there were an estimated 295,000 new cases of all forms of TB and 41,000 deaths, including the nearly 8,000 deaths among HIV-positive TB patients.
3. In 2007, the countries of the region reported 218,000 new cases of all forms of TB and 120,000 cases of smear-positive pulmonary TB, which correspond to 74% and 76%, respectively, of the number of cases estimated by WHO. The region’s 12 priority countries reported more than 80% of all cases of TB, with 2 of them— Brazil and Peru—reporting 50% of the total.
4. The reported incidence of TB in the Americas has shown a downward trend over the past two decades that has become more marked since the adoption of the DOTS strategy in 1996. For 2007, the reported incidence of all forms of TB and smear-positive TB was 25 and 13 per 100,000 inhabitants, respectively. When comparing the rates of Latin America and the Caribbean (LAC, which excludes the United States and Canada) with those of the Americas as a whole, LAC showed higher rates (1.5 times higher), with a greater downward trend.
5. If it maintains this downward trend, the Americas region could reach an incidence level close to 18 cases of all forms of TB per 100,000 inhabitants by 2015.
6. The falling incidence of all forms of tuberculosis since the initiation of the DOTS strategy in the Americas is more accelerated in those countries classified by the Regional Plan as having the lowest TB burden and good DOTS coverage. It is probable that this downward trend in the Region is not completely the result of DOTS implementation and that other factors can also have contributed (among them, improved socioeconomic conditions). Thus, in Latin America and the Caribbean, as the Gross Domestic Product (GDP) per capita increases with stable market prices, TB tends to decrease, with statistically significant trends.
7. Regarding the trend for reported cases of smear-positive pulmonary TB, the following was observed:
8. The gap between reported and estimated cases was minimal in countries with a low estimated TB incidence and high DOTS coverage, and this increased where TB estimates were higher. The biggest difference between new estimated cases and new reported cases was observed in the countries with the greatest tuberculosis burden: Brazil, Colombia, Ecuador, Guatemala, and Haiti.
9. In the Americas region, there was a preponderance of reported cases among males, with a male/female ratio of 1.6. The majority of the cases, for both men and women, came from the economically productive age group. The average age in the region for new smear-positive cases reported in 2007 was 36.5 years (38 for men and 34 for women), with a clear upward trend. The average ages by sex are greater than the regional averages in Scenarios 1A, 1B, and 2.
10. The target to cut prevalence in half by 2015 compared to 1990 has already been reached in the Americas. However, some countries of the Region—among them, Uruguay, Belize, Venezuela, Guatemala, Paraguay, and Guyana—did not reach the indicator that refers to maintaining their current trend.
11. The target for 2015 to cut TB mortality in half compared to 1990 will be easy to reach if the region continues to follow the current pattern. However, some countries of the region ( Uruguay, Venezuela, Guatemala, Paraguay, Haiti, Suriname, and Guyana) did not reach the target.
12. Over the past decade, DOTS coverage has increased in the Americas, with a subsequent increase in the detection of new smear-positive cases. Nonetheless, success in treatment has fallen over the past few years, which indicates that DOTS expansion has taken place at the expense of quality. This drop has come about at the expense of an increase in the cohorts for treatment of non-evaluated cases.
13. A statistically significant inverse correlation can be observed between the detection rate for new cases and the drop in incidence for smear-positive TB, which shows the importance of the activity in the Americas. However, the countries with the greatest burden and lowest DOTS coverage still have not met the target for detection.
14. Only six countries met the targets for 70% detection and 85% successful treatment of cases under DOTS, with the following priority countries not having managed to meet either of these targets: Haiti, the Dominican Republic, Brazil, Ecuador, and Guyana.
15. In the Americas, the number of laboratories carrying out smear tests, mycobacterial cultures, and drug sensitivity tests are above the point of reference recommended for the region. Nevertheless, there are important differences among countries.
16. Over the past few years, the percentage of TB patients evaluated with HIV testing has increased, as has the number of countries reporting this activity. However, coverage for preventive therapy with cotrimoxazole (CMX) and antiretroviral treatment for TB/HIV patients continues to be low.
17. Estimates for the Americas show that the percentage of MDR-TB among new TB cases is anywhere from 2.3% to 16.4% among previously treated cases. Only 23% of all estimated MDR-TB cases were identified. Brazil was the country reporting the most MDR-TB cases in 2007.
18. The number of countries reporting financial information to WHO is increasing yearly. In 2009, the number of countries reporting this information represented 86% of the TB burden in the Americas.
19. Budgets for TB control in the region, represented by 16 countries, have tripled over the past 5 years, reaching US$ 215 million in 2009. The budget is mainly concentrated in the strategic lines of action for DOTS, MDR-TB, and advocacy, communication, and social mobilization (ACSM).
20. The financial deficit for 2009 reached US$ 52 million. The total cost of TB control has grown since 2004 and rose to US$ 275 in 2009.
21. In the region, the governments are the most important source of funding for the national TB programs (NTPs). External sources still represent a small proportion of the total budget.
22. The cost per patient in the region varies from US$ 649 to US$ 2,332. The countries with the lowest costs per patient are Colombia, Nicaragua, and Haiti. The countries with the highest total costs are Ecuador and Peru.