Systematic Veterinary Virology

TRANSMISSION

• The infection is transmitted by both direct and indirect methods. In direct method of transmission the infection spreads from sick animals to susceptible animals through contact. The indirect methods of transmission include feeding of pigs with garbage containing infected meat, through soft ticks of the genus Ornithodoros, which act as biological vector and through fomites. The virus initially enters into a susceptible herd by indirect methods and later spread within herd by both direct and indirect methods. The transmission cycle of ASF virus is given below for academic interest. Appearance of ASF in animals is dependant on
  • close contact between domestic pigs and warthogs that may be harbouring infected tampans;
  • introduction of new pigs into a herd, for example through purchase, for ceremonies or boar loan;
  • introduction of infected pig meat from neighbouring villages;
  • feeding of squil to pigs that contains raw or insufficiently cooked pork and pig remnants or access to such remnants through scavenging;
  • movement of vehicles and people between herds during an outbreak