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How did pneumonic plague differ from bubonic plague?
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Black Death
Flagellants in the Netherlands scourging themselves in atonement, believing that the Black Death is a punishment from God for their sins, 1349.
Bubonic and pneumonic plague are two distinct clinical forms of the disease caused by the bacterium Yersinia pestis. They differ primarily in their transmission, symptoms, and severity.12
- Transmission: Bubonic plague is not directly infectious from person to person; it is typically transmitted to humans through the bite of infected fleas that live on rodents. In contrast, pneumonic plague is highly infectious, as the bacteria can be passed directly between people through respiratory droplets expelled by coughing or sneezing.13
- Symptoms: Bubonic plague is characterized by the development of buboes—painful, swollen lymph nodes, usually in the groin or armpits. Pneumonic plague involves extensive invasion of the lungs, resulting in symptoms similar to severe pneumonia, such as fever, weakness, and shortness of breath, followed by fluid filling the lungs.132
- Severity: While bubonic plague was historically fatal for about half of its victims, pneumonic plague is significantly more dangerous; without treatment, death is almost certain within three to four days. Pneumonic plague can also develop as a secondary complication of untreated bubonic plague.13