@glynmoody I suspect we should consider the centralised sewage system as at least partly to blame, too! Where do all the antibiotics go after all mammals have taken them? And don't we put lots of bacteria to grow there too? Evolution will pressure the quick survival of those bacteria best fitted to the sewer environment.....with constant supply of low levels of antibiotics.
Not sure what the solution is but always remember if you point a finger at anyone there are three pointing back at you!