Bioterrorism
🧨 Bioterrorism: Six organisms are classified as highest-priority ("Category A" by CDC/WHO).
They are highly lethal, easily disseminated, cause public panic, and strain healthcare systems:
Anthrax, Smallpox, Plague, Tularemia, Botulism, and Viral Haemorrhagic Fevers.
In the UK, preparedness falls under the Civil Contingencies Act and NHS England emergency frameworks.
1️⃣ Anthrax (Bacillus anthracis, spore-forming)
- 🔎 Diagnosis: Inhalational form → widened mediastinum (CXR), haemorrhagic mediastinitis.
Cutaneous → black eschar 🩹.
GI → severe sepsis after contaminated meat.
- 🎯 Weaponization: Spores highly stable 🌱, aerosolisable, 45–85% mortality untreated inhalational cases.
- 💊 Treatment: Ciprofloxacin 400 mg TDS (first-line). Add carbapenem (meropenem 2 g TDS / imipenem 1 g QDS) + protein synthesis inhibitor (linezolid, clindamycin, rifampicin, or chloramphenicol).
2️⃣ Smallpox (Variola virus)
- 🔎 Diagnosis: Synchronous vesicular–pustular rash 🌐, fever & rigors precede rash. Centrifugal distribution (face & extremities first).
- 🎯 Weaponization: Population is immunologically naïve (vaccination stopped 1970s). Virions stable in dried scabs 🧫. Mortality ~30% historically.
- 💊 Treatment: Supportive (isolation, fluids, antibiotics for secondary infection). Antivirals: cidofovir, tecovirimat (investigational in UK).
3️⃣ Plague (Yersinia pestis)
- 🔎 Diagnosis: Pneumonic form → cough, haemoptysis, rapid decline 💀. Bubonic → painful buboes. Septicaemic → DIC, purpura fulminans.
- 🎯 Weaponization: Easily spread by droplets 😷, associated with historic "Black Death". Mortality untreated >90% (pneumonic).
- 💊 Treatment: Gentamicin 5 mg/kg OD OR ciprofloxacin 400 mg BD OR doxycycline 200 mg loading then 100 mg BD.
4️⃣ Tularemia (Francisella tularensis)
- 🔎 Diagnosis: Plague-like illness with ulceroglandular lesions 🦠. Pneumonic form is most lethal. Extremely infectious (10 organisms inhaled can cause disease).
- 🎯 Weaponization: Very low infectious dose, stable in environment, incapacitating.
- 💊 Treatment: Same as plague (gentamicin, ciprofloxacin, doxycycline).
5️⃣ Botulism (Clostridium botulinum toxin)
- 🔎 Diagnosis: Descending symmetrical flaccid paralysis 🧑🦽. Diplopia, dysarthria, dysphagia, respiratory muscle weakness. Sensation normal, no fever.
- 🎯 Weaponization: Most potent toxin ☠️. Potential contamination of food/water. Massive ICU/ventilation demand.
- 💊 Treatment: Ventilatory support critical. Botulinum antitoxin halts progression but does not reverse paralysis.
6️⃣ Viral Haemorrhagic Fevers (Ebola, Lassa, Marburg, CCHF)
- 🔎 Diagnosis: Fever & myalgia → shock, haemorrhage, multi-organ failure 🩸. Petechiae & mucosal bleeding common. Case fatality 25–90%.
- 🎯 Weaponization: High fear factor, person-to-person spread possible, limited countermeasures.
- 💊 Treatment: Supportive (fluids, organ support, strict isolation 🧑🔬). Ribavirin helps in Lassa, some arenaviruses & CCHF (loading 30 mg/kg → 16 mg/kg QDS ×4d → 8 mg/kg TDS ×6d, experimental).
💡 Clinical Pearls
- 🔬 Anthrax & tularemia → not contagious (mass exposure concern).
- 🧍 Smallpox & plague → contagious → isolation & ring vaccination vital.
- 💤 Botulism = pure toxin, no fever or inflammation.
- 🧪 VHFs need BSL-4 labs; UK has designated HCID (High Consequence Infectious Disease) centres.
