An anteroposterior X-ray of a patient diagnosed with advanced bilateral pulmonary tuberculosis.

Credit: Wikipedia Commons

In today’s blog, Pranab Chatterjee, tells us how the DOTS strategy has helped decrease Tuberculosis worldwide.

Tuberculosis is a disease which has been a companion of humanity since the earliest periods. The oldest records of the disease in the human have been found from remains of Neolithic Settlement in the Eastern Mediterranean area, dating back to 7000 BC (1). Previously, it was almost always fatal and the numbers of lives claimed by tuberculosis was mind boggling. However, the emergence of streptomycin in 1946 and an understanding of the mechanisms of transmission led to rapid decrease in the numbers. However, in the modern age, it has once again reared up its ugly head, mainly due to the emergence of drug resistance, co-infection with HIV and population explosion, especially in the developing world.

About 15 years ago, the WHO envisioned a strategy to combat tuberculosis. It was known as DOTS: Directly Observed Therapy, Short-course. Simply put, it is a system where a healthcare worker supervises the drug intake by a tuberculosis patient on a regular basis, as indicated by the therapy protocol. It mainly focuses on 5 aspects (2):

a) political commitment with increased and sustained financing,
b) case detection through quality-assured bacteriology,
c) standardized treatment with supervision and patient support,
d) an effective drug supply and management system,
e) monitoring and evaluation system and impact measurement.

DOTS was launched in a major fashion at international, national and regional levels with an integrated, bottom-up system which aimed at finding and treating tuberculosis cases at well-defined regional basis. This led to better case “catching” and diagnosis. Furthermore, the direct observation of drug intake was a simple method to ensure the compliance to medication, which might have otherwise been difficult to achieve owing to the complexity, multiple drugs and long regime.

India has been one of the countries with the best DOTS coverage and DOTS response. In terms of population coverage, India now has the second largest DOTS program in the world. However, India’s DOTS program is the fastest expanding program, and the largest in the world in terms of patients initiated on treatment, placing more than 100,000 patients on treatment every month (3). Having seen the system functioning closely, I have felt that one of the reasons for the success of DOTS in India was the fact that it made use of local human resources optimally to ensure that there was adequate identification, coverage and compliance, followed by observed therapy, and follow up. Understandably, it takes quite a lot in terms of human and financial resources to keep the system going in a country with as heterogeneous and dense population as India, but the continued success of DOTS has justified the resources allocated for this purpose.

In a recent WHO press release (2), there is proof of the success of this strategy. In the 15 years since the institution of DOTS, some 36 million people have been cured of tuberculosis and 8 million tuberculosis related deaths averted. There has been a steady and continued increase in the number of people receiving treatment and getting cured under the DOTS regime. Data from the last 12 months shows that 2.3 million people have been cured. With 87% of treated patients being cured, his exceeds the global target of curing 85% of treated patients.

All this is great, but in my opinion, there are still some lacunae which prevent the total elimination of tuberculosis a reality. The emergence of Multi Drug Resistant (MDR-TB) and the even more lethal Extensively Drug Resistant (XDR-TB) has led to increased fatalities. The poor coverage of the MDR TB and XDR TB patients under existing programs means poorer results. The prohibitive costs of the drug regimens, and the extended time for which they have to be administered is often a limiting factor, especially in programs running in countries of the developing world. The emergence of HIV-TB co-infection, thought better managed than in the past, is yet to reach desired levels to make elimination a reality. The necessity of a stable politico-social environment is a must if national and regional programs to control TB are to be successful. The tumultuous political environment in several African nations, where a great proportion of the affected live, means poorer results in the longer run. The financial meltdown has led to drying up of funds for supplying the necessary drugs to the poorer nations, leading to loss of whatever progress that may have been made in the recent past. Gender inequalities still exist in the identification and treatment of tuberculosis. Out of the 9.4 million TB cases to have occurred in 2008, 3.6 million were females.

However, the numbers are promising as DOTS emerges as one of the most cost efficient public health measures. The need of the hour is to keep up the intensity with which the program is proceeding and somehow, in this difficult financial environment, find a way to keep the resources flowing into the nations that need it the most. Elimination may still be a few years away, but the momentum which has ensured success to this program needs to be maintained.

Sources:

1. Hershkovitz, I; Donoghue, HD; Minnikin, DE; Besra, GS; Lee, OY; Gernaey, AM; Galili, E; Eshed, V et al. (15 October 2008). “Detection and Molecular Characterization of 9000-Year-Old Mycobacterium tuberculosis from a Neolithic Settlement in the Eastern Mediterranean.”. PLoS ONE 3 (10): e3426. doi:10.1371/journal.pone.0003426. PMID 18923677.

2. http://www.who.int/mediacentre/news/releases/2009/tb_report_20091208/en/index.html Accessed on 10th December, 2009

3. http://www.tbcindia.org/ Accessed on 10th December, 2009

More Links:

1. http://www.who.int/tb/publications/global_report/2009/update/en/index.html Global tuberculosis control: a short update to the 2009 report

2. http://www.who.int/whosis/indicators/compendium/2008/4tsr/en/index.html Tuberculosis treatment success under DOTS (percentage)

3. http://www.usaid.gov/our_work/global_health/id/tuberculosis/expanded_response1.html Expanded Response to Tuberculosis: What USAID Will Do

4. http://en.wikipedia.org/wiki/Tuberculosis_treatment#cite_ref-Elzinga2004_5-0 Tuberculosis treatment

5. http://globalhealth.kff.org/Daily-Reports/2009/December/09/GH-120909-Tuberculosis.aspx Kaiser Daily Global Health Policy Report DOTS Has Cured 36M People, Prevented Up To 8M TB Deaths Over 15 Years, WHO Says

This entry was posted on Monday, December 21st, 2009 at 11:00 am and is filed under Blog, Blogroll. You can follow any responses to this entry through the RSS 2.0 feed. You can trackback from your own site.