Multi-drug resistant tuberculosis (MDR-TB) is disease by an isolate of M. tuberculosis resistant to at least isoniazid and rifampicin. Extensively-drug resistant TB (XDR-TB) is a sub-set of MDR-TB which is further resistant to at least two more drugs which are second line drugs and is thus virtually incurable. XDR TB was first described in March 2006 following a joint survey of laboratories by the WHO, IUATLD, and CDC, Atlanta.
XDR-TB is a serious emerging threat to public health and TB control, raising concerns of TB epidemics with severely restricted treatment options that could jeopardize progress made in TB control. To combat this threat. WHO has recommended MDR-TB prevention through sustained high quality DOTS implementation, improvement of laboratory capacity for diagnosis of MDR and XDR TB, prevention of emergence of XDR TB through effective treatment of MDR TB, and to address indiscriminate use of second line anti-TB drugs.
The Revised National TB Control Programme (RNTCP) widely known as DOTS, a WHO recommended strategy, is being implemented in the country. The objective is to achieve cure rate of 85% of new sputum positive cases and to detect at least 70% of such cases.
The country has been consistently achieving the target of 85% treatment success of new sputum positive patients put on treatment for the past several years. It is also detecting 70% of the new estimated infectious cases. It is estimated that the deaths due to TB have declined to less than 5%.
The number of deaths has been brought down from 5 lakh annually in 1990 to 3,70,000 currently. Recent studies conducted by Tuberculosis Research Centre, Chennai suggest that there has been a 12% annual decline in the prevalence of TB. As per the latest estimates, the MDR TB incidence in new cases is less than 3%.
The programme is establishing a network of quality assured accredited laboratories at least one in each large state capable of undertaking culture and drug sensitivity testing for diagnosis of MDR TB and treatment as per DOTS Plus guidelines. MDR TB treatment has been started in the states of Maharashtra and Gujarat and will be extended to entire country in a phased manner by 2010.
This information was given by the Minister for Health & Family Welfare, Dr. Anbumani Ramadoss in a written reply to a question in the Lok Sabha.