The antibiotic colistin is a prime example of increasing antimicrobial resistance (AMR). For many years it was rarely used on humans because of its harmful effects on the kidneys, although it has been used extensively in veterinary medicine. In recent years, however, colistin has again become a last-resort treatment for some patients with specific hard-to-treat bacterial infections. Worryingly, and reflecting the decreasing efficacy of antibiotics in general, the effectiveness of colistin is now also diminishing.

In November 2015, scientists announced the emergence of E. coli bacteria in China carrying the MCR-1 gene, which makes bacteria resistant to colistin. An infection with E. coli bacteria can cause gastroenteritis and even kidney failure. A study in The Lancet medical journal describes this as the ‘breach of the last group of antibiotics’. A woman from Pennsylvania in the US was also found with E. coli bacteria carrying the MCR-1 gene, although the patient proved not to be resistant to all antibiotics. As scientists have succeeded in transferring this colistin resistance to other bacteria, they are now more concerned than ever before that pan-resistant bacteria could develop.

Estimates suggest that the mortality rate due to antimicrobial resistance (AMR) might soar from 700,000 deaths every year worldwide to 10 million a year by 2050. What is more, the cumulative effect of AMR on economic performance could increase to US$ 100bn by 2050.

Nevertheless, these effects can be mitigated or even prevented altogether if new antibiotics are developed and other methods for fighting infectious diseases, such as genetic engineering, become a reality.