In a quiet function in Rajkot on Sunday, March 7, an indigenous leprosy vaccine — the first such in the world — was launched as part of a pilot programme in several districts of Gujarat and in Bihar. The scale of the programme was not proportionate to the size of the achievement; a vaccine developed entirely at the National Institute of Immunology (NII). Here is why the Mycobacterium indicus pranii (MIP) vaccine could be a milestone in the fight against the group of diseases collectively known as Neglected Tropical Diseases (NTD).
What is MIP?
MIP is a non-pathogenic bacteria that has been named after Dr Pran Talwar, who discovered it, and NII, where it was identified. In its heat-killed form, it acts by sprucing up the body’s immunity. Apart from leprosy, it is also being tried as a vaccine against bladder cancer, warts, lung cancer and TB. It has received approval as a leprosy vaccine from the Indian drug regulator, Central Drugs Standard Control Organisation, and the US Food and Drug Administration (FDA). If the field trials in four districts of Gujarat and two in Bihar, launched by Health Minister J P Nadda on Sunday, prove successful, the vaccine may be the country’s most potent weapon in the fight to eliminate a disease still dogged by social stigma. It could also, say officials in the Union health ministry, become part of the national programme against leprosy.
How was the vaccine developed?
Dr Talwar developed the vaccine in the 1990s. Clinical trials were subsequently carried out at the ICMR institute in Agra and the vaccine’s efficacy was tested over a 10-year period — a long process as is the case for all such trials involving communicable diseases. The trials, which concluded in 2000-2001, found the vaccine’s efficacy to be about 70 per cent. Cadilla obtained a licence for it in the mid-2000s.
Who is this vaccine targetting? Why is it being introduced so late in the fight against leprosy?
According to Dr Soumya Swaminathan, secretary, health research, the vaccine would be given to those around patients who are in remission from the disease. She says it is now being introduced into the National Leprosy Elimination Programme (NLEP) because leprosy numbers haven’t dropped as much as the government hoped it would. “Over the last few years we found that new cases were not going down. It had kind of become static and transmission was continuing. We were giving Rifampicin (an antibiotic used to treat bacterial diseases including leprosy) to contacts after remission but now we want to try out this vaccine too. We know its efficacy. What we are trying to find out in these six districts is the feasibility and acceptability of introducing this vaccine in the programme,” she says.
What is the current status of leprosy cases in India?
Caused by the bacterium Mycobacterium leprae, leprosy affects the skin, nervous system, respiratory tract and eyes but is most feared because of the unsightly skin lesions and in very advanced stages, disfigurement and disability. While India has a running national programme for the elimination of the disease, the number of leprosy cases went up from 1,25,785 to 1,27,326 between 2014 and 2015. The Annual New Case Detection Rate (ANCDR) stands at 9.71 per 1,00,000 population. According to the 2015-16 annual report of the National Leprosy Elimination Programme (NLEP), a total of 86,028 leprosy cases are on record as on April 1, 2016, at a Prevalence Rate (PR) of 0.66 per 10,000 population. Elimination is defined as a PR of 1 case per 10,000 population.
Does this mean India has already eliminated leprosy?
Technically yes, but as statistics show, cases are actually rising and some states have regressed. Elimination has to be achieved at the states and the districts, not just at the national level, to break the disease’s cycle. Leprosy spreads by people-to-people contact but is not nearly as contagious as it is made out to be in popular perception. Till date 34 states/ UTs have achieved the level of elimination. One state (Chhattisgarh) and one UT (Dadra & Nagar Haveli) are yet to achieve elimination. Odisha, Delhi, Chandigarh and Lakshadweep have reported PR>1/10,000 population, as on March 31, 2016. Breaking down leprosy incidence at the district level, the annual NLEP report says: “A total of 551 districts (82.36%), of the total 669 districts have PR<1/10,000 population. The number of districts with PR between 1 to 2/10,000, have reduced from 97 to 76. Number of districts with PR>2/10,000 have increased from 40 to 42.”
How is India going about its target of eliminating leprosy by 2018 as mentioned in Finance Minister Arun Jaitley’s budget speech earlier this year?
Under NLEP, leprosy case detection campaigns (LCDC), in line with pulse polio campaign, were launched in the endemic districts — those with a PR of more than 1/10,000 population. Health workers went on a door-to-door basis to identify cases. The first LCDC, in March and April 2016, was conducted in 50 high endemic districts of 7 states covering a population of 75 million. The second LCDC, held in September 2016, was conducted in 163 districts of 20 States and UTs, covering a population of 360 million. Till date, about 31,000 cases have been confirmed. Focused campaigns were conducted in the leprosy hotspots and case detection teams were formed to reach inaccessible areas.