What is the Difference Between Bubonic and Pneumonic Plague

The key difference between bubonic and pneumonic plague is that bubonic plague mainly affects the lymphatic system when the bacterium enters through a skin cut or when an infected flea bites a person, while pneumonic plague mainly affects the lungs when a person inhales aerosolized bacteria.

Plague is an infectious disease caused by the bacterium Yersinia pestis. It is a zoonotic bacterium usually found in small mammals and their fleas. It is transmitted between animals through fleas. There are three main forms of plague: bubonic, pneumonic, and septicemic plague. Bubonic plague affects the lymphatic system, and it is the most common form of plague. Transmission of bubonic plague occurs when an infected flea bites a person or the bacterium enters through a skin cut when contacted with materials contaminated with Y. pestis. Pneumonic plague affects the lungs, and it is the most virulent form of plague. It transmits through the inhalation of aerosolized bacteria.

CONTENTS

1. Overview and Key Difference
2. What is Bubonic Plague
3. What is Pneumonic Plague
4. Similarities – Bubonic and Pneumonic Plague
5. Bubonic vs Pneumonic Plague in Tabular Form
6. Summary – Bubonic vs Pneumonic Plague

What is Bubonic Plague?

Bubonic plague is one of the three types of plague that mainly affects the lymphatic system. The countries with the highest number of bubonic plague cases are the Democratic Republic of the Congo, Madagascar, and Peru. In bubonic plague, once people are exposed to this bacterium, it develops flu-like symptoms, including fever, headaches, and vomiting. It can also cause swollen and painful lymph nodes in the area closest to where the bacteria entered the skin. Moreover, bubonic plague causes dark discolouration of the skin called acral necrosis and occasionally swollen lymph nodes known as buboes.

Bubonic plague is mainly spread through infected fleas from small animals. It may also be a result of exposure to body fluids from a dead plague-infected animal. Normally, mammals such as rabbits, hares, and some cat species are infected with bubonic plague, and they die upon contraction. Diagnosis of bubonic plague can be done through physical examination and finding the bacteria in blood, sputum, or fluid from the lymph nodes. Furthermore, the treatment options for the bubonic plague may include antibiotics such as streptomycin, gentamycin, doxycycline, and vaccines against the plague.

What is Pneumonic Plague?

Pneumonic plague is a form of plague that mainly affects the lungs. It is the second most common form of plague. It is more serious and less common than bubonic plague. Countries with the highest number of cases are the Democratic Republic of the Congo, India, China, Peru, Madagascar, and the United States. The symptoms normally start about three to seven days after exposure. The typical symptoms may include fever, weakness, headache, nausea, shortness of breath, chest pain, coughing, and bloody or watery sputum. Pneumonic plague may occur following an initial bubonic or septicemic plague stage. It can also occur from breathing in airborne droplets from another person or animal infected with pneumonic plague.

Diagnosis of pneumonic plague can be done through physical examination and finding the bacteria in sputum. Furthermore, the treatment options for pneumonic plague include antibiotics such as streptomycin, gentamycin, tetrarcyclin, and choramphenicol.

What are the Similarities Between Bubonic and Pneumonic Plague?

• Bubonic and pneumonic plague are two main different forms of plague.
• Both forms are caused by Yersinia pestis.
• They are prominently seen in Africa and Asia.
• Both forms can be diagnosed through physical examination and by finding bacteria in specific fluids.
• They are treated mainly through antibiotics.

What is the Difference Between Bubonic and Pneumonic Plague?

Bubonic plague mainly affects the lymphatic system, while pneumonic plague mainly affects the lungs. Thus, this is the key difference between bubonic and pneumonic plague. Furthermore, bubonic plague is less serious and more common than the pneumonic plague. On the other hand, pneumonic plague is more serious and less common than bubonic plague.

The below infographic presents the differences between bubonic and pneumonic plague in tabular form for side-by-side comparison.

Summary – Bubonic vs Pneumonic Plague

Plague is a zoonotic disease in humans and other mammals. It is caused by the bacterium Y. pestis. It is commonly seen in Africa, Asia, Europe, and America. Bubonic plague is the most common form of plague that mainly affects the lymphatic system. In bubonic plague, painful swollen lymph nodes or ‘buboes’ can be seen. Pneumonic plague is the most virulent form of plague and mainly affects the lungs. Early diagnosis and treatment are necessary for pneumonic plague. Otherwise, it can be rapidly fatal. Detection or identification of Y. pestis from a sample of pus from a bubo, blood, or sputum is the best way to confirmation of this infection. So, this summarizes the difference between bubonic and pneumonic plague.

Reference:

1. “Bubonic Plague (Black Death): What Is It, Symptoms, Treatment.” Cleveland Clinic.
2. Herndon, Jaime. “Systemic Lupus Erythematosus: Causes, Symptoms, and Treatment.” Healthline, Healthline Media.

Image Courtesy:

1. “Plague -buboes”  By Centers for Disease Control and Prevention: Public Health Image Library (PHIL) (Public Domain) via Commons Wikimedia
2. “Pneumonic plague” By Ashfaq – (CC BY-SA 4.0) via Commons Wikimedia