Bubonic Plague: Symptoms, Historical Impact, and Modern Treatment

Bubonic Plague (Yersinia pestis)

Transmission

• Flea bites (Xenopsylla cheopis) from infected rodents.
• Direct contact with infected tissues/fluids.
• Respiratory droplets (pneumonic plague).

Symptoms (Incubation 2–6 days)

• Sudden fever, chills, headache, myalgia, weakness.
• Buboes: Painful, swollen lymph nodes (groin, axilla, neck) – hallmark.
• Septicemic: Bacteremia → DIC, necrosis, shock.
• Pneumonic: Cough, hemoptysis, dyspnea – person-to-person spread.

Historical Impact

• Plague of Justinian (541–549): 25–50M deaths.
• Black Death (1347–1351): 75–200M deaths (30–60% of Europe).
• Third Pandemic (1855–1960): 12M+ deaths, mostly India/China.

Modern Treatment

• Antibiotics: Streptomycin, gentamicin, doxycycline, ciprofloxacin, chloramphenicol.
• Early treatment reduces mortality from 30–60% to <10%.
• Post-exposure prophylaxis for contacts.
• Vaccine not commercially available.

Plague remains endemic in rodent populations (western US, Africa, Asia); rare human cases occur annually.