Guidelines
Anthrax

Anthrax

Note

Anthrax is a notifiable disease

Etiology

Bacillus anthracis

Anthrax is an acute zoonotic infectious disease caused by the bacterium Bacillus anthracis. It most commonly occurs in wild and domestic animals, such as cattle, sheep, goats, camels, antelopes, and other herbivores. B. anthracis spores can live in the soil for many years.

It occurs in humans when they are exposed to infected animals or tissue from infected animals. The incubation period is usually 1-3 days. Anthrax is a notifiable disease

  • Exposure to B. anthracis spores by handling products from infected animals or by inhaling anthrax spores from contaminated animal products
  • Anthrax can also be spread by eating undercooked meat from infected animals

Clinical Features

  • 95% of anthrax infections occur through skin cut or abrasion
  • Starts as raised itchy bump that resembles an insect bite
  • Within 1-2 days, it develops into a vesicle and then a painless ulcer, usually 1-3 cm in diameter, with a characteristic black necrotic (dying) area in the centre (eschar)
  • Lymph glands in adjacent area may swell
  • About 20% of untreated cutaneous anthrax results in death
  • Initial symptoms resemble a cold
  • After several days, symptoms may progress to severe breathing problems and shock
  • Inhalation anthrax is usually fatal
  • Acute inflammation of the intestinal tract
  • Initial signs of nausea, loss of appetite, vomiting and fever
  • Then abdominal pain, vomiting blod, and severe diarrhoea
  • Intestinal anthrax results in death in 25% to 60% of the cases

Investigations

  • Isolation of Bacillus anthracis from blood, skin lesions, or respiratory secretions
  • Or measure specific antibiotics in the blood of persons with suspected infection

Management