Systematic Veterinary Virology

CHRONIC FORM

• The chronic form is characterised by dullness, capricious appetite, pyrexia and diarrhoea for up to 1 month. Weight loss, hair loss, dermatitis and discoloration of abdomen or ears are the other symptoms.
• A chronically infected pig may have a disproportionately large head relative to the small trunk.
• The affected pigs may stand with arched backs and their hind legs placed under the body. The animals may recover followed by relapse and death.
• Chronic form occurs in vaccinated herds or can also be caused by less virulent strains of CSFV.