Sitting in A&E at 5am on a Saturday is not my idea of fun. However, it is nothing short of awe inspiring seeing the doctors and nurses at the JR in action. So it was that I sat admiring the skill and dedication of the staff in Paediatric A&E last week, after my son had an asthma attack.

Thanks to modern medicine he is okay, and so were all the other children we saw during our stay. However, there were a lot of nasty coughs and one parent of a two-year-old kicked up a fuss demanding antibiotics. She obviously thought that antibiotics would cure any type of infection. Antibiotics are brilliant – they have saved hundreds of thousands of people from an oozy, infectious death. BUT antibiotics are only effective against bacteria. So if the infection is caused by a virus they just won’t work.

Because they are so effective against bacterial infections we have over-used them for a long time. This has led to resistance. The problem with being human, and at the top of the food chain, is that we forget how good other creatures are at surviving. Bacteria are absolutely genius at it. They have been around for a lot longer than us mere humans and have managed to adapt to all kinds of environments and threats to their existence. It is because of this killer survival instinct that some bacteria have managed to outwit our antibiotics and become resistant.

Antibiotic resistance can start when just one bacteria manages to survive a course of antibiotics. This “Schwarzenegger” bacteria has undergone genetic changes that allow it fight back. Like Arnold and his extraordinary ability to grow muscle, genetic changes can occur by chance and are called point mutations. Another type of genetic change can result from two different bacteria swapping some genes in the cellular soup. This is called horizontal gene transfer and is very common. If you take a look at the genes of most bacteria you will find genetic material from all kinds of other organisms.

These genetic mutations give our Schwarzenegger bacteria new tactics for evading antibiotics including:

* producing molecules that change or deactivate the antibiotic itself;
* morphing itself so that the place where the antibiotic normally attaches no longer fits – like changing the locks on your door and trying to get in with the old key; 
* being happy to change tastes. The bacteria aren’t bothered by an antibiotic that blocks a particular nutrient – they are not fussy eaters; 
* clearing the antibiotic quickly either by producing molecules that stop the antibiotic entering the bacteria’s cellular home or by scheduling extra rubbish collections to dump more of the antibiotic from the cell.

Although some resistance to antibiotics will naturally happen, we have accelerated resistance by taking antibiotics too often (no point giving the bacteria more practice than necessary!) and incorrectly. If we don’t take a full course of antibiotics those Schwarzeneggers are still hanging in there. They soon perk up and start multiplying – a whole army of angry Schwarzeneggers!