Is it possible to contract the plague by kissing a wild chipmunk?"
The causative agent of the plague, Yersinia pestis, can be indirectly (via a flea vector) or directly (via exposure to infectious fluid or a bite) transmitted by rodents. In the western United States in particular, Y. pestis is endemic, and ground squirrels, prairie dogs, chipmunks, and woodrats are important reservoirs (see Cecil Medicine Ch. 320). US National parks have signs warning against feeding squirrels and chipmunks for this reason. You can read more about it in a national park brochure . Chipmunks and squirrels indirectly and directly transmit a variety of other diseases as well, including Tularemia (Cecil Ch 319) and various tick and flea borne encephalitides.