The global superbug crisis

Drug resistance has been called one of the biggest threats to global health, food security, and development by the World Health Organisation. If antimicrobials stop working, doctors won’t have effective drugs to treat deadly infections. Currently the problem is thought to kill 700,000 people worldwide - one person a minute - though these figures have been disputed by some academics. The death toll is expected to rise to 10 million by 2050 if no action is taken, with 4.7m of those deaths in Asia. Common procedures like joint replacements, Caesarean sections, organ transplants and chemotherapy could also become too risky to carry out.

The Bureau has tracked more than 2,800 tonnes of colistin for use on animals shipped to India, Vietnam, South Korea, Russia, Nepal, Guatemala, Colombia, Bolivia, Mexico and El Salvador in 2016. The total is likely to be higher as the product may be shipped under its brand name rather than being labelled as colistin - and to other countries for which customs data is not made public. By comparison, the UK uses less than a tonne a year of colistin in agriculture.

Colistin is manufactured by two companies in India but the country is also importing at least 150 tonnes of the drug each year.

India has been called the epicentre of the global drug resistance crisis. A combination of factors described as a “perfect storm” have come together to hasten the spread of superbugs. Unregulated sale of the drugs for human or animal use - accessed without prescription or diagnosis - has led to unchecked consumption and misuse. India has a large population, some of whom defecate in the open, and waste is often poured untreated into rivers and lakes. This creates the perfect conditions for bugs to share resistance.

Poor sanitation means people often catch infections that require treatment with antibiotics. Overuse of the drugs in hospitals has created antibiotic resistant hotspots, and poor infection control means these bugs spread within the hospital and into the community. Some of the pharmaceutical companies manufacturing antibiotics have also failed to dispose of antibiotic-ridden waste properly, fuelling the spread of resistant bugs in the environment.

All of these factors have led to high rates of resistance. In India 57 per cent of Klebsiella pneumoniae bacteria - which commonly cause urine, lung and bloodstream infections - are resistant to last line antibiotics known as carbapenems. In the UK by comparison the figure is below one per cent. Doctors in some areas of India see patients with pan-resistant infections (immune to nearly all antibiotics) at least once a month. The government does not collect figures on how many people are dying of resistant infections but one study estimates drug-resistant infections kill 58,000 newborn babies in India every year.

Bugs bred in India spread globally. One which particularly worried scientists is a gene called New Delhi metallo-beta-lactamase 1 (NDM-1), which makes bugs resistant to carbapenem antibiotics. This has been dubbed “the nightmare bacteria” by the Centers for Disease Prevention or Control in the US because it kills half the patients who develop a bloodstream infection.

NDM-1 was first found in a patient who acquired it in India in 2008 and has since spread all over the world, with over 1,100 laboratory confirmed cases in the UK since 2003. It is far from the only one being spread from India. The mcr-1 gene which confers colistin resistance spread round the world in three years. Some 11 per cent of travellers to India came home colonised with mcr-1 bacteria, a recent study found.