Superbug threat

An old nemesis is turning into a deadlier avatar, and medical scientists are worried. It is malaria, to which half the world’s population is still at risk. Malarial infections continue to afflict around 2 million people every year; the casualty rate remains over 4,20,000. It has forced countries to undertake massive programmes for its control and eradication. But claims of victory over malaria have proved premature time and again. Chloroquine was once considered a surefire malaria parasite killer, but a chloroquine-resistant strain spread through Asia and Africa during the Sixties and Seventies, claiming millions of lives. Then came the drug sulphadoxine-pyrimethamine (SP), but before long, the parasite became resistant to SP first in Cambodia and laid low African countries again. The next wonder drug is artemisinin, rediscovered from traditiol Chinese medicine, for which Chinese pharmacologist Youyou Tu got the Nobel Prize for Medicine in 2015. Extracted from sweet wormwood, powerful artemisinin has a shortcoming. It has a short half-life, for which reason it is used in combition with longer-acting anti-malarial drugs. As per WHO estimates, the use of artemisinin to spearhead global anti-malarial efforts has nearly halved the number of deaths due to the disease from 839,000 in 2000.

Currently, dihydro-artemisinin used with piperaquine as partner (DHA-PPQ combition) is considered the most advanced treatment for malaria. Well, not any longer, according to a recent study. Evidence is mounting that ‘Plasmodium Falciparum’, the bacteria causing malaria, has evolved into another killer mutant strain that is resistant to DHA-PPQ. This fitter, more transmissible, multi-drug resistant ‘superbug’ has already taken hold in parts of Cambodia, Laos, Thailand and Myanmar. After doctors found artemisinin combition therapies (ACTs) failing with patients, the alarm rang. A joint team of researchers of Mahidol University in Thailand and Oxford University have now sounded the warning that if not tackled from a ‘global public health emergency perspective’, the new malaria superbug would next sweep into India and onwards to Africa. A team at the Indian Institute of Science in Bangalore is now experimenting with a combition of curcumin (extracted from turmeric) with ACT, having observed its capacity to prime the human immune system against malaria parasites. But these are early days, and there is far to go. In medical circles, the worry is that if artemisinin loses its effectiveness, there is no widely accepted immediate substitute, unlike during previous outbreaks of resistant malaria.

The emergence of malaria superbug is but the latest instance of ‘antibiotic resistance’, a threat to public health considered so pressing that at a UN summit last year, it was put on par with the spread of HIV and dreaded Ebola. Put simply, it is the threat of bacteria evolving and becoming resistant to antibiotics faster than scientists can create newer ones in the lab. There are several factors leading to growth of antibiotic resistance — particularly due to over-prescription and misuse of antibiotics (even for viral ailments), as well as for widespread use of drugs to make livestock animals grow faster (because the microbes inside animals become more resistant and infect humans). In India, antibiotic resistance is a serious problem due to dumping of cheap antibiotics in the market, unnecessary prescription and over-the-counter sale of antibiotics. This, coupled with high prevalence of infectious diseases and poor public health systems, is why diseases like malaria and tuberculosis are becoming difficult to treat in the country. Recently, the Drug Controller General of India (DCGI) had to issue a directive to chemists and drug makers to strictly follow norms while selling antibiotics. For a malaria-prone state like Assam, with its creaking public health system and many ‘pharmacists’ selling drugs without requisite qualification, the situation bears careful watching. The fear is that the new resistant malaria parasite strain, which researchers believe is lurking in remote pockets inside Myanmar, may easily spread to the Northeast region. This is not a threat our public health authority can afford to be ignorant or complacent about.