Over the years I've read many times how over prescription of anti-biotics as meant that they are becoming less and less effective.
What you may not know is that in parts of Eastern Europe they don't use anti-biotics but instead use Bacteriophages (they were once in every Red Army soldiers kit bag). Antibiotics work by eliminating may types of bacteria in one go wheras Bacteriophages concentrate on individual bacteria. Because of this the west concentrated on the use of Anti-biotics however even today Bacteriopahges are used in the East to treat the likes of Gangrene.
Now scientists are looking at phages to counter bugs like MRSA. For more info.