Plague is a potentially deadly disease caused by a bacterium (Yersinia pestis) that comes from rodents. Fleas on rodents can also spread this disease.

There are three ways plague can make people ill:

Pneumonic plague affects the lungs. An infected person can spread the disease by sneezing, coughing, or otherwise releasing saliva droplets that are inhaled by another person. If a person does not get antibiotics within 24 hours of the first symptoms, pneumonic plague can cause respiratory failure, shock, and rapid death. Symptoms usually include fever, weakness, and shortness of breath.

Bubonic plague spreads through the bite of a flea infected with the plague bacterium. Symptoms of bubonic plague include fever, fatigue, and swollen, tender lymph glands in the neck, armpits, or groin.

Septicemic plague occurs when bacteria enter the bloodstream and multiply. Symptoms of septicemic plague include fever, belly pain, purplish skin, and shock.

Prevention of the plague requires adequate sanitation. After diagnosis of the plague, the infected person is isolated from others to prevent the spread of the disease. Treatment includes antibiotics, rest, fluids, and pain medicines.