The first case anywhere in the world of a strain of gonorrhea resistant to all known antibiotics was reported late last month. The diagnosis was made in England, but it appears that the infection came from an encounter in south-east Asia. Antibiotic resistance is a global problem, and can’t be confined to any one part of the world for long. Last autumn a woman died in the US of an infection apparently picked up in an Indian hospital which was impervious to all 14 antibiotics in her hospital; later tests showed it was also resistant to the other 12 drugs available to the Centers for Disease Control and Prevention.

The dangers of antibiotic resistance are by now well understood, even if action to diminish them is slow and uncoordinated. The growth of superbugs is not just caused by overprescription in developed countries and completely uncontrolled usage in developing countries, where they are rationed only by price. It is also a product of the widespread use of antibiotics in factory farming, where they are used to keep animal populations at a density which would be impossible in nature. In all these cases, we have set up evolutionary pressures which favour the emergence of antibiotic-resistant strains of bacteria, and evolution has responded in its usual creative way. Around half of the detected cases of infection with the campylobacter bacterium in chickens in British shops involve antibiotic-resistant strains. Campylobacter is unpleasant, but seldom deadly, and can in any case be killed by thorough cooking.

Now fresh research has shown up a new and largely unsuspected means by which industrialised food processing threatens human health. Trehalose is a form of sugar found in nature that is stable at high temperatures. The discovery of a new technique for mass producing it led to widespread adoption in the processed food industry both in the US and Europe after the US Food and Drug Administration recognised that it was safe for humans in 2000. This was followed by outbreaks of hospital infections in countries from Kuwait to Canada, all caused by the gut bacterium Clostridium difficile. There are now two strains of C diff which have evolved mechanisms to consume low concentrations of trehalose and thus flourish at the expense of others. In one case, the newly voracious bugs also produce a more virulent toxin.

This is not as frightening and widespread a threat as the rise of antibiotic resistance, but it remains a chilling example of the complex unpredictability of our interactions with the natural world. The law of unintended consequences is powerful. No one could have imagined that a more efficient way to produce ice-cream might lead to the growth of hospital infections. The real difficulty in both cases is that the costs of industrial food production are not paid by the food processors and farmers who profit most from it. Only coordinated international action can ever fix that – and time is running out.