Responding to TB in Asia: More of the same will brew drug resistance
07 March, 2007
Pakistan, China, India and Indonesia are home to two-in-three of the world's tuberculosis (TB) cases and the countries are expanding coverage of its TB programme at record-breaking speed. In its shadow, drug resistance is also upping the pace. Is there something fundamentally awry with the response to TB in Asia? Some Asian experts think more of the same is sufficient – but has the time come to re-think the way TB is tackled?
Amid recent concerns about the possible emergence of drug resistant TB in India, a member of the government's committee on TB control outlined the national strategy for addressing the problem: "Unfortunately research scientists are yet to come up with medicine for XDR-TB. Therefore it is time to focus on DOTS and restrict the new form of TB," said Dr Rajendra Prasad.
DOTS (or directly-observed treatment short-course) is the internationally-recommended TB control strategy that includes standardized case detection, treatment and patient support. It requires consistent drug supply and effective monitoring systems. India has adopted and implemented DOTS in various parts of the country since 1993. Full national DOTS coverage was reportedly achieved at the end of March 2006, with an estimated treatment success rate of 86%.
But is it really "time to focus on DOTS" more intensively? According to the World Health Organization (WHO), drug resistant TB is a symptom of poor programme performance. If we hope to change the outcome, and decrease the proportion of drug resistant TB, doesn't the DOTS model need to be adapted or its implementation improved? More of the same might only compound the TB drug resistance threat.
Despite recent DOTS coverage gains, many communities in the country remain underserved by TB services. Rural settings, poor communities and mobile populations, for example, are subject to social and economic factors that often lead to incomplete or inappropriate treatment. In addition, TB diagnosis is difficult among people living with HIV – a growing proportion of people with TB in India.
The country does indeed need more and better TB drugs and diagnostics in the public sector. But better strategies to make TB control programmes work more effectively for the most vulnerable and hard to reach communities are also essential to improving treatment adherence and, as a consequence, reducing drug resistance.
The 2006 annual Indian TB Report said: "Drug-resistant TB has frequently been encountered in India and its presence has been known virtually from the time anti-TB drugs were introduced for the treatment of TB". Over the next five years (2006-2010), Drug Resistant Surveillance is being carried out in 10 states of India to gauge the extent of problem.
From March 2007, India will also launch a 'DOTS-Plus' programme. DOTS-Plus, conceived by the WHO and its partners, is a strategy for the management of multi-drug resistant TB (MDR-TB). It uses second-line anti-TB drugs to cure MDR-TB. DOTS-Plus pilot projects are only recommended in settings where the DOTS strategy is fully in place to protect against the creation of further drug resistance.
Potential ways to improve DOTS programme performance are well known and documented. One is to move beyond approaches that place health centres at the centre of TB services, to community-based versions of DOTS. The need to attend to problems faced by frontline workers is also important. For example, provision of transport and other logistical support to increase work performance, geographic coverage and patient compliance. Another key area is improving patient-health worker communication, which in turn works to reduce TB-related stigma, raise local awareness and improve treatment literacy.
The India 'DOTS Plus' programme will make second-line drugs available in the country for people with MDR-TB. Just as the widespread use, or misuse, of first-line anti-TB drugs can lead to loss of drug sensitivity, the arrival of less effective, more toxic and costlier second-line TB drugs may give rise to various new forms of drug resistant TB.
The emergence of extensively drug resistant TB (XDR-TB) in India therefore cannot be ruled out – especially if we do not attend to the factors that are known impediments to effective TB responses and treatment in the country already.
More DOTS without better implementation might be just what is not needed.
(Bobby Ramakant is a public health and development Journalist, a part of The Key Correspondent Team coordinated by Health and Development Networks. Website: www.TheCorrespondent.org , email: email@example.com )