BACTERIA

Bacillus anthracis animated Bacillus anthracis infections

Bacillus anthracis appearance

  • Gram-positive rods
  • nonmotile
  • spore-forming (oval spores located centrally in an unswollen sporangium)
  • usually encapsulated (a protein capsule composed of poly-D-gamma-glutamic acid)

Infections caused by Bacillus anthracis

Anthrax is a serious infectious disease caused by Gram positive, rod-shaped bacteria known as Bacillus anthracis. Anthrax can be found naturally in soil and commonly affects domestic and wild animals around the world. Although it is rare, people can get sick with anthrax if they come in contact with infected animals or contaminated animal products.

People get infected with anthrax when spores get into the body. When anthrax spores get inside the body, they can be “activated.” When they become active, the bacteria can multiply, spread out in the body, produce toxins (poisons), and cause severe illness. This can happen when people breathe in spores, eat food or drink water that is contaminated with spores, or get spores in a cut or scrape in the skin.

B. anthracis was the first bacterium conclusively demonstrated to cause disease, by Robert Koch in 1876. Until the 20th century, anthrax infections killed hundreds of thousands of animals and people worldwide each year (Wikipedia).The species name anthracis is from the Greek anthrax , meaning "coal" and referring to the most common form of the disease, cutaneous anthrax, in which large, black skin lesions are formed.

Types of Anthrax

  • Cutaneous anthrax
  • Pulmonary anthrax
  • Gastrointestinal anthrax

Bacillus anthracis treatment
Should be guided by in vitro susceptibility tests!!
Selection of appropriate antibiotics depends on diagnosis!!

Fluoroquinolones
  • ciprofloxacin
Tetracyclines
  • doxycycline
Penicillins
  • penicillin G
Alternatives:
  • erythromycin
  • vancomycin


Bacillus anthracis vaccination

Vaccines against anthrax for use in livestock and humans have had a prominent place in the history of medicine, from Pasteur's pioneering 19th-century work with cattle (the second effective vaccine ever) to the controversial 20th century use of a modern product (BioThrax) to protect American troops against the use of anthrax in biological warfare. Human anthrax vaccines were developed by the Soviet Union in the late 1930s and in the US and UK in the 1950s. The current FDA-approved US vaccine was formulated in the 1960s. Currently administered human anthrax vaccines include acellular (United States) and live spore (Russia) varieties. All currently used anthrax vaccines show considerable local and general reactogenicity (erythema, induration, soreness, fever) and serious adverse reactions occur in about 1% of recipients (Wikipedia).

  • Wikipedia
  • CDC
  • Links:

    CDC


    Wikipedia


    Textbook of bacteriology


    Colony appearance


    Bacillus anthracis Bacillus anthracis Gram stain Bacillus anthracis