That's not surprising. There's plague all over CA in the ground squirrel population.
Check out
http://www.cdc.gov/ncidod/dvbid/plague/epi.htm to see if there's plague where you live!
However, if you look at
http://www.cdc.gov/ncidod/dvbid/plague/facts.htm , you find that there are very few actual human cases of plague. Conditions have to be just right for spread, and unless you actually get infected it doesn't matter what antibiotics do or do not work against the bacterium (
Yersinia pestis).
Really, you should be concerned about antibiotic resistance in run-of-the-mill (or at least common) infectious agents. Critical care ward are increasingly finding strains of
Staphylococcus aureus and
Pseudomonas spp., for instance, that aren't responsive to any of the conventional antibiotics, and document multidrug resistance has been rising rapidly over the past decade.
Unless we find a new class (or two) of antibiotics -- and use them judiciously -- the era of the miracle drug may be coming to an end less than a century after it began.