New technologies can halve TB diagnosis time

New technologies can halve TB diagnosis time

Tuberculosis (TB) kills one person every 90 seconds in India and about 1000 people every day, according to the World Health Organization (WHO). India accounts for over 20 percent of TB cases worldwide, with over 1.9 million recorded cases per year as of last count. The air-borne disease is estimated to cost the Indian government about US $3 billion in indirect costs and US$ 300 million in direct costs.

Given the social and economic costs of TB, the Indian government has adopted an aggressive approach to combating the disease through its Directly Observed Treatment Short Course (DOTS) programme, launched nationally under the Revised National TB Control Programme (RNTCP) in 1997.

Multi-drug resistant (MDR) tuberculosis is especially complicated, and the government is currently aiming to increase the number of accredited laboratories in India to diagnose this type of TB.

Dr Behera, Director of the LRS Institute of TB & Respiratory Diseases, explains that the most crucial aspect to treating MDR TB is a quick and accurate diagnosis. Two new methods for diagnosis that have not yet been implemented on a large scale are line probe assays (LPA) and liquid culture media.

Behera explains that liquid, as opposed to solid, culture media cuts the diagnosis time down from 12 to 3 weeks, while line probe assays are even quicker, with a diagnosis time of just 48 hours.

Listen to Dr Behera talk about new and upcoming methods to diagnose TB. Click here...

Both methods, however, are expensive. Behera says that while solid culture media costs under 100, liquid culture media costs around 3000. This cost is further enhanced by the need for sophisticated equipment and laboratories, along with an uninterrupted power supply. LPA too is expensive, however the exact cost is yet to be determined. “ So far LPA has been done under the WHO," says Behera. “Whether it is feasible in India is being evaluated."

Despite the high cost, Behera expects that the RNTCP will soon offer these technologies. “If you think of the lives saved, it is worthwhile going for these methods and I believe the programme is thinking about it," he says. “Even if it is very costly, the diagnosis time is so short and so many tests can be done at one go that it doesn’t need to be made available in every district. Perhaps in every state it can be done at just one location or even two or three states can have one location," he says.

The LPA method is already being implemented in some areas, including Gujarat and Andhra Pradesh, and Behera expects this will be scaled up in other parts of the country over the next two to three years.