Leprosy bacteria becoming drug-resistant in India

India is likely to face fresh challenge in its efforts to eliminate leprosy, with a World Health Organisation (WHO) surveillance network detecting significant levels of drug resistance against two medicines that are used to treat the bacterial infection.

The first survey on the prevalence of anti-microbial resistance in leprosy-causing bugs painted India and Brazil in red as the two nations with the maximum drug resistance for the disease, which is traditionally associated with social stigma.

For nearly seven years (between 2009 and 2015), the WHO surveillance network examined hundreds of leprosy cases in 19 countries to find out whether the bug (Mycobacterium leprae) developed resistance against medicines like rifampicin, dapsone and ofloxacin.

In India, rifampicin resistance was seen in more than 8% of new cases, whereas it is less among existing patients.

The anti-microbial data from the two major endemic countries exposed the seriousness of the problem. Out of 32 new cases tested in Brazil and 98 cases tested in India, rifampicin resistance was in 15.6% and 8.2% cases respectively.

Among the relapsed leprosy cases (321 tested in Brazil and 254 in India), drug resistance was seen in 8.4% and 3.9% cases respectively. There were also multiple cases of rifampicin and dapsone resistance, as well as dapsone and ofloxacin resistance.

India accounts for nearly 60% of the world's leprosy burden. The number of cases is also on the rise nearly 13 years after New Delhi reduced leprosy prevalence rate to less than one case per 10,000 population.

New cases

In 2016-17, there were 1,35,485 new cases in India as against 1,27,334 in 2015, according to information furnished by the Union Health Ministry to the MPs. The ministry attributed the reason behind 6.4% increase in new cases to the new strategy of active case detection.

However, in the last 10 years, the number of new leprosy cases never dropped below the 1,00,000 mark. In years like 2011-12 and 2012-13, there was a significant jump of more than 7,000 new cases in a year.

"The study reveals a potential problem that the leprosy scientific community did not foresee, and prompts to establish an enhanced and 'proper' surveillance system. For these reasons, AMR (anti-microbial resistance) monitoring is now mentioned under the core areas of intervention in the Global Leprosy Strategy 2016-2020," says the survey published in the journal of Clinical Microbiology and Infection.