"We are entering, it seems, the era that medical scientists have long feared, when the power of the post-war generation of drugs -- the antibiotics -- is slipping away, no longer able to contain and destroy the agents of infectious disease" (S Newman and T Lobstein, issue 36 of The Food Magazine).

Why don't antibiotics always work?
Because they are used too frequently and indiscriminately.

If antibiotics are used too much, more resistant strains of bacteria will evolve. The evolution of bacterial resistance to antibiotics occurs by natural selection. If bacteria are exposed to an antibiotic, only those bacteria that are resistant to the antibiotic will survive to reproduce.

Antibiotics can be used to successfully treat illness because they can kill all of the harmful bacteria before resistance can evolve. But if everyone, even healthy people, took antibiotics all the time, bacteria would evolve to become resistant to these antibiotics.

Antibiotics in animal feed
Antibiotics are often routinely included in animal feed. The medication is included routinely, firstly because it prevents the spread of diseases when animals are kept in crowded conditions, and secondly because animals which take antibiotics grow more rapidly. The antibiotics appear to be able to increase the efficiency of the animals' digestion. So antibiotics give farmers an economic advantage by producing rapidly growing animals without the need for extra feed.

But routinely giving healthy animals antibiotics can be harmful to both humans and animals. There is some evidence of cross resistance, where bacteria that developed resistance to a veterinary drug have also shown resistance to human medication.

The antibiotic, avoparcin, is used in poultry production to suppress the development of diseases which can break out in intensive animal production. However, there are concerns that the use of avoparcin is leading to the development of resistance to a similar antibiotic, vancomycin, often used as a lifesaving antibiotic to treat human disease when other antibiotics may have failed. The European Commission declared in 1998 that avoparcin and several other antibiotics will be banned from animal feed.

Sweden has banned antibiotics in animal feed
In 1986, Sweden opted to ban antibiotics from routine use in animal feed, reducing overall tonnage of antibiotics used by forty percent. Antibiotics are only given to farm animals for curing disease and after a veterinary prescription. Furthermore, Sweden claims to be the main European Union producer of salmonella-free chickens.