Background and history

This is an uncommon disease of pigs in most parts of the world, including the EU where it is notifiable. It is caused by the bacterium Bacillus anthracis and is characterised by acute illness, fever, respiratory distress and rapid death.

Human health

Care should be taken in handling diseased pigs or carcasses because the disease is transmissible to the human

Clinical signs

• Acute illness.
• Bloody faeces.
• Haemorrhage from the nose.
• Fever.
• Respiratory distress.
• Sudden death.
• Swollen discoloured neck.
• Blue skin.
• Unusual in piglets.

Anthrax should be suspected if a sow is found dead and post-mortem examination shows copious blood tinged-mucus and large haemorrhagic lymph nodes under the skin of the neck and in the abdomen. The post-mortem examination should be discontinued immediately and veterinary help sought.

Acute infection with Haemophilus parasuis (glassers disease) in primary medicated early weaning (MEW) or SPF immunologically naive sows may result in similar signs and lesions to anthrax.

Diagnosis

Diagnosis is confirmed by taking smears for microscopy and swabs for culture from the affected tissues. (Note that samples are not made from blood as they would be with cattle).

The veterinarian should not fix the smears by flaming because this destroys the bacterial capsule which is a diagnostic feature. Smears are best fixed in Zenker's fluid.

Causes

• Contaminated feed or water.
• Contaminated soil.
• Other dead animals.

Prevention

Effective vaccines are available in some countries for both pigs and people

Treatment

The anthrax bacillus is sensitive to penicillin.