The ticking time bomb is giving signals that it is coming to the end of its countdown. The National Tuberculosis Institute (NTI), Bangalore, has confirmed eight cases all reporting TB germs resistant to all known TB drugs. A confirmatory notice has also been sent to the Central TB Division or CTD, New Delhi.
Twelve patients with symptoms of Tuberculosis (TB) were admitted to the Hinduja hospital on January 6th. Doctors soon declared them infected with Totally Drug Resistant TB (TDR-TB). Three out of the 12 died soon after. Sputum samples from all the 12 were sent for testing. Eight came out positive for a strain more resistant than earlier thought.
Triggering the time-bomb
Resistance to drugs generally results from the overuse of antibiotics. It’s simple evolution, really. Few of a population of TB germs may develop a genetic factor enabling it to resist a drug administered on the patient, say drug A. These few are the only surviving members of the population. Now, these multiply, giving rise to the next generation of germs resistant to this particular drug. When it infects another patient, a new drug – say drug B – is needed. Some members of this new population can then develop resistance to drug B, while retaining its resistance to drug A. Over prescription of medicines known to work on TB germs accelerates this process and very soon we get TB germs resistant to multiple drugs. This is what is referred to as Multi-Drug Resistant TB (MDR-TB).
TDR-TB refers to TB which are resistant to first line drugs. First line drugs are drugs proven to work against the bacteria, with the least amount of side-effects. There is a second line, which may not be as effective, or may produce more side-effects, or maybe not as well clinically tested as first line drugs. Second line drugs are used when first line ones fail. MDR-TB is resistant to many second line drugs as well.
Eight of the Hinduja patients were infected with TB that showed resistance to both first and second-line drugs, making it Extremely Drug Resistant TB (XXDR-TB). However, WHO doesn’t recognize this classification. The case has been documented on the Directly Observable Treatment Shortcourse Plus (DOTS+) log. Doctors are still to figure out the line of treatment for these eight patients.
The TB timebomb is ticking… maybe beyond our control now!