Plague, in humans, doesn't pop up a lot. Generally there are between one and seventeen cases per year in the United States, and only about a thousand in total since 1900. Anyone of any age can get contract the infection, but probability of exposure increases with outdoor activity. Lie down with small mammals, get up with plague.
People who want to minimize their possibility can go snow-camping, or camping during the coldest part of the winter -- although getting the plague may seem the more pleasurable option. Cases of plague are very rare, and antibiotics are effective, but the disease is no joke. It still carries a 11 percent overall mortality rate.
In 2012, two major cases of bubonic plague hit the news. An Oregon man attempted to dislodge a partially-eaten mouse in his pet cat's throat. The mouse was most likely infected. The cat bit the man, which would have left large open wounds for the bacteria to get into. He was treated, but lost his fingers and toes to infection before he recovered.
In another case, a seven-year-old girl in Colorado put her sweater on the ground next to a dead squirrel. The fleas on the squirrel may have jumped to the sweater, which the girl subsequently tied around her waist. Within a day she had a high fever and dangerous septicemia, and doctors were stumped. When they questioned her mother, the woman remembered the dead squirrel, and the girl was treated with antibiotics. She recovered within the week.
Both cases point to one of the obstacles in treatment of the plague. It's incredibly well-known, but still almost unthinkable. No one seriously considers the plague these days, and a few scattered cases throughout an entire nation doesn't mean that people will recognize it when it comes.
Remembering, and mentioning, exposure to dead or dying animals is key. As for efforts to eliminate it completely - although they've been considered, it would take too much extensive trapping and testing of animals to be easily accomplished while the plague is still so rare. It looks like we'll continue getting the plague for the foreseeable future.