The actual term Expiration Date refers to the last date a food should be eaten or used. Last means last -- proceed at your own risk. Other, more commonly spotted terms are:  1 Sell by date. 2  The labeling sell by tells the store how long to display the product for sale. 3  You should buy the product before the date expires. 4  This is basically a guide for the retailer, so the store knows when to pull the item.
When an animal or person is infected with Yersinia pestis, the bacteria affect the lymph system, causing the characteristic symptoms. If bubonic plague is left untreated, plague bacteria can quickly multiply in the bloodstream, causing septicemic plague. The bacteria could also progress to the lungs, causing pneumonic plague.
The bacteria that are the causes of bubonic plague are typically transmitted through the bite of an infected flea or rodent. In rare cases, Yersinia pestis bacteria on a piece of contaminated clothing or other material used by an infected person can enter through an opening in your skin.ersinia pestis bacteria are usually only found in certain parts of the world, such as Africa, Asia, and South America. Approximately 1,000 to 3,000 cases of bubonic plague are reported each year. Between 10 to 20 of these cases are in the United States, most commonly in rural areas of the Southwest.