Anthrax

Generalities
Agent	- Bacteria: Bacillus anthracis, Gram positive, aerobic, rod-shaped, encapsulated, spore-forming, and non-motile - Can be used in biological warfare
Incubation period	1-7 days (up to 60 days for inhalation form)
Period of transmissibility	- Person-to-person transmission rare: direct contact with skin lesions (cutaneous form) - Contaminated articles and soils remain infective for several years
Reservoir	- Animals (herbivores both livestock and wildlife) who shed the bacilli in terminal hemorrhages or blood at death - Soil and environment where spores may remain viable for years - Dried or processed skins and hides of infected animals, that may harbor spores for years
Modes of transmission	- Cutaneous form: contact with tissues, hair, wool, hides, products of infected animals; contact with soil containing spores or contaminated with bone meal; possible flies bite that fed on infected animals - Inhalation form: inhalation of spore-laden dust in industries (tanning hides, processing wool or bone products…); accidental inhalation in laboratory; intentional release of spores using aerosol devices including mail-items - Digestive form: ingestion of contaminated undercooked meat - Injection form: injection of contaminated heroin
Clinical presentation	- Cutaneous form (95% of cases)on exposed skin: evolutive lesions from itchiness, to papular, vesicular, then eschar with or without surrounding redness with extensive oedema. Untreated lesions may progress to regional lymph nodes and/or to septicemia. Case fatality is 5-20%. - Inhalation form (rare): mild respiratory infection that evolves in 3-6 days to acute respiratory distress. At Chest XR, a mediastinal widening (with or without pleural effusion) is observed. Meningitis may occur. Case fatality is almost 100% with delayed or no treatment. - Intestinal form (rare): fever with intestinal symptoms (abdominal pain and diarrhea). Case fatality is 25-75%. - Oropharyngeal form: a painless mucosal lesion in the oral cavity or oropharynx, with cervical adenopathy, edema, pharyngitis, fever, and possibly septicemia - Injection form: similar to cutaneous form, but there may be infection deep under the skin or in the muscle. Complications: septicemia, meningitis, death
Resources
Case definition	MOPH circular no. 98 (2015)
Forms	- General reporting form - Anthrax investigation form
Data	No reported cases in Lebanon from 2000 to 2015