Bacillus species

BACK TO INFECTIOUS AGENTS AND PARASITES BACK TO BACTERIA

Bacillus anthracis

• CAR bacillus in URT infection in cattle and URT infection in rabbits

• Can cause vascular fragility, leading to haemorrhagic disease.

Overview

• Mostly non-pathogenic environmental organisms
• Bacillus anthracis causes anthrax
• Bacillus licheniformis may cause shoradic abortions in cattle and sheep
• Bacillus cereus causes food poisoning in humans and mastitis in cows

Characteristics

• Large, Gram positive rods
• Produce endospores
• Aerobes or facultative anaerobes
• Grow on non-enriched media
• Motile
• Catalase positive, oxidase negative
• Bacillus anthracis colonies are up to 5mm diameter, flat, dry, grey, with a ground-glass appearance; curled outgrowthsfrom the edge of the colony give a 'medusa head' appearance; non-haemolytic (differentiate from Bacillus cereus)
• Bacillus licheniformis forms dull, rough, wrinkled colonies, with hair-like outgrowths
• Biochemical tests for identification
• Can often tolerate adverse environmental conditions