Epidemiology

• Bubonic plague (“black death”) pandemics have occurred several times throughout the centuries
• Less than 20 cases annually in US
• Most common in SW states

---

Etiology

• Yersinia pestis infection
• Gram-negative cocco-bacillus
• Reservoir: rodents

Physiology

• Transmission: bite from infected flea
• Incubation: 1-6 days (may be as short as 2-4 days)
• Bubo formation (regional necrotizing lymphadenitis)

---

Diagnosis

• Sputum GS/Cult+Sens: may reveal gram negative cocco-bacillus
  • Bipolar (“safety pin”) staining with Wright, Giemsa, or Wayson stains
  • Confirmatory
• CXR/Chest CT patterns:
• PCR, antigen detection, immunoassays: available from state ref labs and CDC

---

Clinical

• Pneumonic plague: any case of pneumonic plague should be considered a possible bioterrorism event
  1) Productive cough:
  2) Chest pain:
  3) Dyspnea:
  4) Hemoptysis:
  5) GI symptoms: abdominal pain
  6) Acral gangrene:

---

Treatment

-Streptomycin + gent:
-Alternative: tetracycline
-Alternative: fluoroquinolones

Infection control: human-to-human transmission by respiratory droplets from pulmonary involvement
-Highly contagious
-Respiratory isolation for at least the first 48 hrs of therapy

Post-Exposure Prophylaxis: dooxy x 7 days

Vaccine: none available

---

Prognosis

• Case-fatality rate without treatment: near 100%
• Case-fatality rate with streptomycin: 5-14%

---

References

• xxx