Cutaneous and inhalation disease have occurred in past bioterrorist incidents

Gastrointestinal Tract: (ingestion of spores – rare).

Comment: Spores can be inhaled into the lower respiratory tract. The infectious dose of B. anthracis in humans by any route is not precisely known. In primates, the LD50 (i.e., the dose required to kill 50% of animals) for an aerosol challenge with B. anthracis is estimated to be 8,000–50,000 spores; the infectious dose may be as low as 1-3 spores.

Gastrointestinal Tract: 15-72 hours.

Features

Gastrointestinal Tract: if intestinal form, necrotic, ulcerated edematous lesions develop in intestines with fever, nausea and vomiting, progression to hematemesis and bloody diarrhea; 25-60% fatal

Gastrointestinal Tract: blood and ascites fluid, stool samples, rectal swabs, and swabs of oropharyngeal lesions if present for culture, polymerase chain reaction and immunohistochemistry.

Aerosolized powder, environmental exposures: Highly infectious if aerosolized.

Aerosolized powder, environmental exposures: Respirator (N95 mask or Powered Air Purifying Respirators), protective clothing; decontamination of persons with powder on them (Notice to Readers: Occupational Health Guidelines for Remediation Workers at Bacillus anthracis-Contaminated Sites — United States, 2001–2002).

Hand hygiene: Handwashing for 30-60 seconds with soap and water or 2% chlorhexidene gluconate after spore contact (alcohol handrubs inactive against spores [Weber DJ JAMA 2003; 289:1274]).

Post-exposure prophylaxis following environmental exposure: 60 days of antimicrobials (either doxycycline, ciprofloxacin, or levofloxacin) and post-exposure vaccine under IND.

Comment: Toxin ingested or potentially delivered by aerosol in bioterrorist incidents. LD50 (lethal dose for 50% of experimental animals) for type A is 0.001 μg/ml/kg.

1. use of sharps safety devices and safe work practices;
2. hand hygiene;
3. barrier protection against blood and body fluids upon entry into room (single gloves and fluid- resistant or impermeable gown, face/eye protection with masks, goggles or face shields); and
4. appropriate waste handling.

Use N95 or higher respirators when performing aerosol-generating procedures. In settings where AIIRs are unavailable or the large numbers of patients cannot be accommodated by existing AIIRs, observe Droplet Precautions (plus Standard Precautions and Contact Precautions) and segregate patients from those not suspected of VHF infection. Limit blooddraws to those essential to care. See text for discussion and Appendix A for recommendations for naturally occurring VHFs.

Chemoprophylaxis: Consider antibiotic prophylaxis for HCWs with close contact exposure.

Transmission by the airborne route is a rare event; Airborne Precautions is recommended when possible, but in the event of mass exposures, barrier precautions and containment within a designated area are most important.^{204, 212}

Only immune HCWs to care for pts; post-exposure vaccine within 4 days.

Vaccinia: HCWs cover vaccination site with gauze and semi-permeable dressing until scab separates (≥21 days). Observe hand hygiene.

Adverse events with virus-containing lesions: Standard plus Contact Precautions until all lesions crusted.

Vaccinia adverse events with lesions containing infectious virus include inadvertent autoinoculation, ocular lesions (blepharitis, conjunctivitis), generalized vaccinia, progressive vaccinia, eczema vaccinatum; bacterial superinfection also requires addition of contact precautions if exudates cannot be contained. ^{216, 217}

Typhoidal: fever, prostration, weight loss and frequently an associated pneumonia.

Laboratory workers who encounter/handle cultures of this organism are at high risk for disease if exposed.