African swine fever

Definition

A highly lethal hemorrhagic disease of domestic pigs (Sus scrofa domesticus) caused by African swine fever virus (ASFV), a large double-stranded DNA virus in the family Asfarviridae. The disease is endemic to sub-Saharan Africa, where it persists in a sylvatic cycle involving warthogs, bushpigs, and soft ticks of the genus Ornithodoros, which serve as biological vectors and long-term reservoirs. In domestic pigs, ASFV causes fever, hemorrhage, and mortality rates approaching 100%; there is no vaccine. The virus does not infect humans. Outbreaks outside Africa—now established in Europe and Asia—represent major threats to global pork production and demonstrate how arthropod-borne pathogens bridge wildlife, livestock, and agricultural systems.

Etymology

From geographic origin (first described in Kenya, 1921) and host specificity for swine.

Example

In East African savannas, Ornithodoros porcinus ticks maintain ASFV for years without feeding, then transmit the virus to warthog piglets in their burrows; when domestic pigs contact infected tick populations or warthog carcasses, explosive outbreaks can kill entire herds within days.

Synonyms

• ASF
• pig plague
• warthog disease

Related Terms

• vector-borne disease
• Ornithodoros
• Arbovirus
• reservoir host
• emerging infectious disease
• veterinary entomology
• biological vector
• sylvatic cycle

Usage Notes

Distinguish from classical swine fever (caused by a pestivirus, not tick-borne). 'ASF' is the standard abbreviation in veterinary and entomological literature. The tick vector is essential to the epidemiology; control strategies often target Ornithodoros habitat rather than only pig vaccination (which remains unavailable).