﻿Dame Sally Davies, the Chief Medical Officer for England, has likened the problem of antibiotic resistance to the risks presented by international terrorism. While this might sound like an exaggeration, the threat was actually, if anything, understated. Each year, the global number of deaths to which bacterial resistance contributes far outstrips those caused by terrorist attacks. 
While it is difficult to track the global impact of antibiotic resistance across all bacterial species, the World Health Organization estimates that for tuberculosis alone multi-drug resistance accounts for more than 150,000 deaths each year. Antibiotic resistance is no longer an abstract risk: this is now a war. 
In the past hundred years, our expectations of life and survival have changed beyond all recognition. At the beginning of the twentieth century, life expectancy in the UK stood at around 47 years of age for a man and 50 for a woman, a number heavily affected by the very high rate of infant mortality in those days. Around a third of all deaths occurred in children under the age of five, largely because of infectious disease. 
In contrast, a child born in Britain today has a better than one in four chance of reaching their 100th birthday. For this we have public health systems, vaccination and antibiotics to thank. It is by these means – the prevention and treatment of illnesses caused by microorganisms – that the real war against disease is principally won. 
Elsewhere, we have pushed the limits of survival, notably in intensive care. This, the specialism in which I chose to train, is where antibiotic resistant organisms are most prevalent. Here, powerful antibiotics, essential in the treatment of life-threatening illness, are used routinely. These drugs decimate ordinary bacteria. But what they leave behind are hardy species that have begun to learn tricks that allow them to evade antibiotic drugs.