Pneumonic Plague
Primary pneumonic plague is caused by infection with the Yersinia pestis bacteria, transmitted through tiny droplets in the air. The secondary form of pneumonic plague can result from bubonic plague. Plague is still present in certain regions of Africa, Asia, and the Americas, but it is no longer found in Europe.
At a Glance
- Pneumonic plague is a severe bacterial infection.
- It can occur independently (primary pneumonic plague) or as a result of bubonic plague (secondary pneumonic plague).
- In primary pneumonic plague, the infection occurs through airborne droplets.
- Plague is still found in certain areas of Africa, Asia, and the Americas.
- Pneumonic plague is no longer present in Germany and Europe.
- Plague can be treated with antibiotics.
Note: The information in this text cannot replace a medical examination and should not be used for self-diagnosis or treatment.
What is Pneumonic Plague?
Historically known as the “Black Death,” plague is an infectious disease caused by the Yersinia pestis bacteria. Pneumonic plague is the most severe form of plague and can occur either as an independent disease (primary pneumonic plague) or as a result of bubonic plague (secondary pneumonic plague). The disease can be cured if treated promptly with antibiotics.
What are Infectious Diseases?
You can learn about the conditions that doctors refer to as infectious diseases, what triggers these diseases, and how they spread from the video below.
What Symptoms are Seen in Pneumonic Plague?
Primary pneumonic plague is transmitted through droplets. There is an incubation period of one to three days between exposure to the pathogen and the appearance of initial symptoms.
After infection with the pathogen, symptoms resembling the flu suddenly appear. The condition of the infected person deteriorates rapidly. General symptoms are similar to those of bubonic plague and include fatigue, headache, vomiting, fever, chills, altered consciousness, and enlargement of the liver and spleen.
In addition to serious respiratory symptoms such as shortness of breath, productive painful cough, and chest pain, other critical pneumonic plague symptoms triggered by sepsis may occur:
- Circulatory collapse
- Organ failure
- Bleeding
- Skin discoloration with clotting disorders
- Limb necrosis
What Causes Pneumonic Plague?
Pneumonic plague is caused by the Yersinia pestis bacteria. In primary pneumonic plague, the infection occurs through inhalation of infectious droplets.
A distinction is made between primary and secondary pneumonic plague. In the primary form, pathogens are transmitted by a person with pneumonic plague. The secondary form occurs when the disease spreads to the lungs from a person with bubonic plague. In this case, the bacteria can be transmitted in tiny droplets released when coughing or sneezing, although this is rare.
How Common is Plague?
There were several major plague outbreaks in Europe in past centuries: the 6th, 13th, 15th, and 19th centuries. Estimates suggest that over 100 million people died as a result of these outbreaks, making it a significant historical event.
Due to improved hygiene conditions, plague infections have become rare worldwide but are not entirely eradicated. Between 2010 and 2015, the World Health Organization reported a total of 3,248 cases of all forms of plague globally, with 584 cases being fatal.
Plague still occurs in specific regions of Africa, the Americas, and Asia, primarily in tropical and subtropical areas between approximately 40 degrees north and south latitude.
Madagascar has the highest number of plague infections, with over a hundred cases per year. Other countries with rare plague cases include:
- Democratic Republic of the Congo
- Peru
- China
- India
- Malawi
- Mozambique
- Zimbabwe
- Tanzania
- Vietnam
- Uganda
The United States is the only country outside tropical and subtropical regions where plague is seen. No plague cases have been recorded in Germany in recent decades, even among people entering the country.
How Does Pneumonic Plague Progress?
Pneumonic plague is the most severe form of plague.
The plague bacteria produce a toxin. If not treated quickly, the disease usually leads to death within 24 hours. In pneumonic plague, in addition to general symptoms like fever, specific and severe respiratory symptoms such as shortness of breath, cough, and chest pain occur. Respiratory failure and shock may also develop.
How Can Pneumonic Plague Be Prevented?
There is no general vaccine available for plague. Prophylactic antibiotics can be given to individuals in contact with people suffering from plague.
How is Pneumonic Plague Diagnosed?
In countries where isolated plague cases are observed, the risk of transmission for travelers from Germany and Europe is considered low, except for Madagascar. Therefore, diagnostic steps are described here solely for completeness.
Initial symptoms are obtained from questioning the potentially ill person:
- Has the person been in a risk area in recent days?
- Is there known plague infection in the risk area?
- Has the person had contact with plague patients?
If pneumonic plague is suspected, blood or sputum samples are examined. The bacteria can be directly detected using specialized methods. In Germany, there are two specialized laboratories for suspected plague cases.
How is Pneumonic Plague Treated?
People with pneumonic plague should be hospitalized as soon as possible and treated with appropriate antibiotics.
It must be ensured at the beginning and during treatment that the plague pathogen does not become resistant to the used medication.