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.
Bubonic plague: In this form of the infection, bacteria infiltrate the lymph nodes, causing enlarged, painful, tender lymph nodes called buboes. Accompanying symptoms are fever, chills, headaches, and weakness. If not treated, the infection can spread to other areas of the body.verview. Plague is an infectious disease caused by bacteria called Yersinia pestis. These bacteria are found mainly in rodents, particularly rats, and in the fleas that feed on them. Other animals and humans usually contract the bacteria from rodent or flea bites.