Bubonic plague is an infectious disease that causes swollen, painful lymph nodes. It caused the deaths of more than 25 million people in the 14th century. The disease still occurs in many parts of the world.
A bacterium called Yersinia pestis causes plague. These bacteria can be present in small mammals and the fleas that feed on their blood.
This article explores bubonic plague in more detail, including its history, symptoms, and treatment.
Non-human animals can transmit the bacteria that cause bubonic plague to people. The disease is uncommon in modern times due to advances in living conditions and antibiotics. However, bubonic plague still exists in many parts of the world.
The Centers for Disease Control and Prevention (CDC) states that there is
The bacterium that causes bubonic plague has existed for
In 1347, ships carrying rats with the plague arrived in Sicily. From there, the plague spread quickly across Europe. Over 25 million people died between 1347 and 1352 as a result. This was at least a third of the population of Europe at the time.
Outbreaks of bubonic plague continued to resurface over the next 400 years. Two-thirds of the population of Genoa and Naples died due to the disease between 1656 and 1657.
Between 1665 and 1666, around 100,000 people in London died due to the disease. Reports indicate that 100,000 people also died in Vienna in 1679 because of bubonic plague. Additionally, 100,000 people died in Russia between 1770 and 1771 because of this plague.
The World Health Organization (WHO) notes that in total, bubonic plague was responsible for the deaths of
Bubonic plague still exists.
The WHO states that plague is present in
The three countries where plague occurs most often are:
- Democratic Republic of the Congo
Madagascar has reported cases of bubonic plague almost every year. These cases typically occur during the epidemic season, which is between September and April.
The CDC notes that
Additionally, the CDC highlights that most plague cases affecting people in the United States occur in the following regions:
- Northern New Mexico
- Northern Arizona
- Southern Colorado
- Southern Oregon
- Far Western Nevada
The CDC also states that more than 80% of plague diagnoses in the United States have been bubonic plague.
Generally, a person who has bubonic plague will develop symptoms
Once bubonic plague bacteria enter a person’s body, they travel via the lymphatic system to the closest lymph node. The bacteria then replicate inside the lymph node, causing it to swell and feel tender and painful.
Other symptoms of the bubonic plague include:
The CDC notes that the
A person may also develop plague if they have direct contact with fluid or tissue from an animal with the disease or one that has died from it.
If a healthcare professional suspects a person has bubonic plague, they will request samples of the person’s:
- lymph node cells
Those samples are then sent to a laboratory for testing. Laboratory technicians can provide preliminary test results for these samples in
A healthcare professional will start treatment for suspected plague
The CDC notes that between 1990 and 2010, the mortality rate for plague in the United States was
However, the mortality rate for bubonic plague may be higher in other countries. The CDC states that it can be difficult to assess the mortality rate in people living in low or middle income countries as few cases are reliably diagnosed and reported.
The WHO notes that the case-fatality ratio for bubonic plague is
If a person does not receive treatment for bubonic plague, it can spread to their blood. From there, the bacteria can spread quickly around a person’s body. This can cause a severe condition called septicemic plague. This form of plague is often fatal.
One place untreated bubonic plague can spread to is a person’s lungs. This can cause a person to develop pneumonic plague, which is more severe than bubonic plague. Without treatment, it is always fatal.
The following methods may help a person
- limiting potential rodent habitats in the yard by removing rock and wood piles, brush, and trash
- keeping pet and wild animal foods in sealed containers
- wearing gloves when handling live or dead animals that may have plague
- contacting the local health department about disposal of dead animals
- using insect repellent containing diethyltoluamide (DEET) when doing outdoor activities, such as working outside
- using flea control products on pets and getting veterinary care if pets become sick
- preventing dogs or cats that roam freely in areas where plague is present to sleep on the bed
Bubonic plague is an infectious disease that the bacteria Yersinia pestis causes. It has been around for thousands of years and is still present in many parts of the world.
Bubonic plague can lead to a person developing buboes. These can become pus-filled open sores as the disease advances.
A healthcare professional can typically prescribe antibiotics to treat bubonic plague. Without treatment, the disease can develop into more severe forms of plague.
A person can help prevent Yersinia pestis transmission in various ways, including applying flea control products on their pets and keeping their yard free from potential rodent habitats.