pneumonic plague

pathology

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July 1, 2026

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Pneumonic plague is a severe, highly infectious form of plague caused by the bacterium Yersinia pestis. It primarily affects the lungs, leading to symptoms like fever, weakness, and shortness of breath. Fluid can accumulate in the lungs, and without prompt treatment, it is almost always fatal within three to four days.12

Pneumonic plague can develop as a complication of bubonic plague or directly through inhaling infectious droplets expelled by an infected person's cough or sneeze. This direct person-to-person transmission makes it particularly dangerous. While modern antibiotics are effective, early diagnosis and treatment are crucial for survival.1

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plague
Nature of the disease
…has three clinical forms: bubonic, pneumonic, and septicemic. Bubonic plague is the best-known form in popular lore, and indeed it constitutes about three-fourths of plague cases. It is also the least dangerous form of plague, accounting today for virtually no deaths and in the past killing only half of its…
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…has three clinical forms: bubonic, pneumonic, and septicemic. Bubonic plague is the best-known form in popular lore, and indeed it constitutes about three-fourths of plague cases. It is also the least dangerous form of plague, accounting today for virtually no deaths and in the past killing only half of its…
Read More

bubonic plague
…forms being septicemic plague and pneumonic plague, bubonic plague is relatively uncommon, with roughly 1,000–2,000 cases occurring worldwide each year, most frequently in parts of Africa, Asia, and South America. The designation bubonic stems from the Greek word for “groin,” reflecting the characteristic buboes, or swellings, that develop in that…
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…forms being septicemic plague and pneumonic plague, bubonic plague is relatively uncommon, with roughly 1,000–2,000 cases occurring worldwide each year, most frequently in parts of Africa, Asia, and South America. The designation bubonic stems from the Greek word for “groin,” reflecting the characteristic buboes, or swellings, that develop in that…
Read More