Janet,
Remember, it is not the person who is resistant to the antibiotic, it is the
germs that the person harbors.  Resistance is most likely when someone takes
the drug for a few days, feels better, then discontinues it.  Then the
stronger (more antibiotic resistant) germs reproduce.  Do this a few times and
you have multidrug resistant bugs.  Was your mastitis hospital aquired?
Hospitals are the source of some of the "best" germs, due to the constant
selective pressure of antibiotics and germicides.  If even one resistant germ
is left behind, it can have millions of babies by tomorrow....
Just another one of my 'pet peeves',
Catherine Watson Genna, IBCLC  NYC  [log in to unmask]