Bubonic plague
Bubonic plague is a serious bacterial infection caused by the bacterium Bubonic plague. It is one form of plague and is usually spread to humans through bites from infected fleas that live on rodents.
Historically, plague caused some of the deadliest outbreaks in human history, including the Black Death.
What causes bubonic plague?
The disease is caused by the bacterium Yersinia pestis. Infection commonly occurs through:
Bite from an infected flea
Contact with infected animals (especially rodents)
Handling contaminated animal tissue
Symptoms
Symptoms usually appear 2–8 days after exposure and may include:
Sudden high fever
Chills
Weakness and fatigue
Headache
Painful, swollen lymph nodes (“buboes”) — commonly in the groin, armpit, or neck
The swollen lymph nodes are what give bubonic plague its name.
Is it dangerous?
Yes. Without treatment, plague can become severe and spread into:
Septicemic plague (bloodstream infection)
Pneumonic plague (can spread person-to-person through respiratory droplets)
But with modern antibiotics and early treatment, survival rates are much higher.
Treatment
Doctors typically treat plague with antibiotics and supportive medical care. Early diagnosis matters.
Is plague still around today?
Yes—but it is rare and usually appears as isolated cases or small outbreaks in some parts of the world. It is not the same as a historical large-scale pandemic situation today.
If someone develops sudden fever plus swollen lymph nodes after animal exposure or flea exposure, they should seek medical care promptly.