Southeast Asia has a quarter of the world's poor and a third of its tuberculosis burden, with an estimated 4.9 million infected persons.
According to recent estimates from the World Health Organization (WHO), over 500,000 cases of multidrug-resistant tuberculosis (MDR-TB) occur annually worldwide—including 50,000 extensively drug-resistant tuberculosis (XDR-TB) cases. Southeast Asia has 28% of the world's MDR-TB cases, with India heading the list. But there are no national data for this and many developing countries on XDR-TB, and most cases are detected ad hoc among patients with MDR-TB not responding to treatment.
A March report from the WHO South-East Asia Regional Office cautions that despite marked improvement in detection and management of tuberculosis cases in national programs, an estimated one third of both regular and resistant cases in the region still go undetected or are treated outside national health programs with poor outcomes (Bull. World. Health. Organ. 88, 164, 2010). These patients not only transmit the disease but also often develop drug resistance.
In most countries, national programs are not designed to track and treat individual cases to curb drug resistance. For example, India's revised national tuberculosis control program designed in the 1990s “addressed the clinical treatment of MDR-TB without developing a public health response to reduce its spread,” says Jacob John, advisor at the department of virology and microbiology at Christian Medical College–Vellore in Tamil Nadu, India. “The same error should not be repeated with XDR-TB.”
Laboratory diagnostic capacity for MDR-TB and XDR-TB is the main limitation, says Nani Nair, regional advisor at WHO South-East Asia Regional Office's department of communicable diseases. This needs tremendous scale-up of infrastructure, trained staff, lab equipment and supplies, Nair told Nature Medicine.
The report warned that with the current status quo the region will not achieve the UN millennium development goal of reducing tuberculosis prevalence and deaths to half the 1990 rate by 2015.