How pretty is this bug? And it is one of the major causes of diarrhoea, vomiting and all the associated ills when you are not careful of what you eat when travelling. So now there is this patch that has the same toxins produced by the E.Coli. Kind of primes your immune system so if you do catch the real bug it will not affect you terribly.
Stomach bugs picked up during foreign travel may be prevented by wearing a patch impregnated by toxins produced by the E. coli bacterium. US research published in the Lancet medical journal found the patch was 75% effective against diarrhoea attacks caused by E. coli among volunteers.
Patch-wearers who did fall ill recovered far more quickly, it said. Their patch contains the poisons produced by E.coli, with the idea that this primes the immune system to cope better when confronted with the real thing. (Link)