The plague is a serious infectious disease caused by the bacterium Yersinia pestis. It primarily affects humans and other mammals and is usually spread by the bite of infected fleas that live on rodents. There are three main types of plague: bubonic, septicemic, and pneumonic. Bubonic plague, the most common form, causes symptoms like fever, chills, weakness, and painful swollen lymph nodes called buboes. Septicemic plague infects the blood and can cause tissue death, while pneumonic plague affects the lungs and is the most severe form, capable of spreading from person to person through respiratory droplets. If untreated, plague can be deadly, but it is curable with antibiotics if treated promptly. Historically, the plague caused devastating pandemics such as the Black Death in the 14th century, which killed millions of people in Europe. Nowadays, it is rare due to improved sanitation but still occurs in some rural areas of the world, including parts of the United States, Africa, and Asia. Early treatment is crucial, especially for pneumonic plague, which can be fatal within 24 hours of symptom onset if not treated. In summary, plague is a bacterial disease transmitted mainly by fleas from rodents to humans, with three major forms showing different symptoms and severity, treatable by antibiotics if caught early.
