African swine fever

Alert

African swine fever is prohibited matter.

Outbreaks have been reported in Eastern Europe, the Russian Federation and Asia (China, Hong Kong Administrative region, Vietnam, Cambodia, Mongolia, Myanmar, Democratic People’s Republic of Korea, Lao People’s Democratic Republic, the Philippines, South Korea and Timor-Leste).

International outbreaks are a reminder that animal diseases can spread quickly and do not respect international borders.

Early detection and reporting of African swine fever is critical to rapid containment of this disease.

If you suspect the presence of African swine fever, you must report it to Biosecurity Queensland on 13 25 23 or contact the Emergency Disease Watch Hotline on 1800 675 888.

Description

African swine fever (ASF) is an infectious viral disease that can affect domestic and feral pigs of all ages. Forms of the disease range from severe to very mild. In its most severe form, up to 100% of pigs may be affected and die. There is no treatment or vaccine available.

Pigs usually become infected through direct contact with infected pigs, fomites (e.g. contaminated equipment) or through ingestion of material containing infected pig meat or pig products. Biting flies and ticks can also spread the virus.

You must comply with Australia's strict quarantine laws. Unauthorised importation of meat or animal products is prohibited to protect against diseases such as ASF.

The international outbreaks reinforce the importance of farm biosecurity and in particular, never feeding swill to pigs. Swill is food (or food scraps) that contain animal matter (e.g. meat, eggs, meat products or illegally imported dairy products) or vegetable waste that has been contaminated by animal matter.

African swine fever is different to swine influenza.

Cause

A virus of the Asfarviridae family.

Distribution

African swine fever (ASF) is present in most of sub-Saharan Africa and in Sardinia. Since 2018, there have been outbreaks in Eastern Europe, the Russian Federation and Asia (China, Hong Kong Administrative region, Vietnam, Cambodia, Mongolia, Myanmar, Democratic People’s Republic of Korea, Lao People’s Democratic Republic, the Philippines, South Korea and Timor-Leste). Outbreaks are managed by respective authorities.

There are no recorded occurrences in Australia.

Life cycle

The course of the acute form of the disease is from 1–7 days. In less acute forms, clinical signs can last 3–4 weeks.

Affected animals

  • Pigs – domestic and feral

Symptoms

Clinical signs vary according to the form of disease.

In the peracute form, pigs may:

  • be found dead with no prior clinical signs.

In the acute form, pigs may:

  • have a fever
  • lose their appetite, or have an irregular appetite
  • show incoordination
  • be reluctant to move and often lie down
  • display redness or blue blotching of the skin on ears, nose and limbs
  • produce nasal and eye discharges
  • abort a pregnancy
  • vomit
  • develop dysentery or diarrhoea.

In the subacute form, pigs will:

  • display clinical signs as per the acute form
  • generally display milder clinical signs that may last 3-4 weeks.

In the chronic form, pigs may:

  • have recurrent fever
  • fail to thrive
  • develop pneumonia
  • develop arthritis
  • develop skin ulcers
  • suffer complicating secondary infections often resulting in death.

Impacts

China produces about 500 million pigs per year, which represents about half of the world's production. Widespread outbreaks could have significant implications for the international demand for pork meat.

Export trade in pigs and pig products would cease if ASF infected Australian pigs. Loss of export markets would result in domestic oversupply and resultant falls in pricing. Pig producers would likely experience significant socio-economic impacts.

How it is spread

The soft argasid tick maintains a source of ASF virus in African warthog populations. Similar ticks are associated with kangaroos in Australia though their role under Australian conditions is not known.

Pigs can become infected by:

  • eating contaminated pork products or feed
  • direct contact with infected pigs
  • contact with contaminated equipment.

Bloodsucking insects feeding on infected pigs can mechanically transmit the virus within herds.

International spread has been associated with the swill feeding of garbage. All Australian states and territories have laws against feeding prohibited feed to pigs (swill).

Risk period

The virus is:

  • stable in a wide range of acid and alkaline levels (pH 4–10) and temperatures, including below freezing
  • viable in contaminated pig pens for at least 1 month
  • viable for many months in raw unprocessed frozen meat
  • inactivated by heating to above 60°C for 30 minutes.

Pigs can remain carriers of the virus for long periods, perhaps for life.

Prevention

We all have a role to play to protect against African swine fever.

Pig keepers

  • Have a biosecurity plan in place and ensure all workers and visitors are aware of your biosecurity rules.
  • Do not feed pigs prohibited feed for pigs and poultry (swill)—its best to feed pigs commercial pig feed.
  • Swill is material that:
    • contains, or may contain, the carcass of a mammal or bird
    • contains, or may contain, material derived from a mammal or bird (including meat, eggs, blood, faeces)
    • has been in contact with either of these (including food or food scraps from a restaurant, hotel or home that may have been in contact with meat or meat products or other material derived from a mammal or bird).
  • Ensure items and equipment coming on to or going off of your farm are clean.
  • Clean and disinfect any equipment shared with other farms.
  • Practice good hygiene—wear clean clothes and footwear when visiting a property with pigs.
  • Prevent visitors from having unnecessary indirect or direct contact with your pigs.
  • Prevent contact between farmed and feral pigs.
  • Check you are registered as a biosecurity entity and make sure your contact and registration details are up-to-date.
  • Ensure you complete all movement requirements when moving pigs
  • If you suspect the presence of African swine fever, you must report it to Biosecurity Queensland on 13 25 23 immediately.
  • Find information to protect your farm from African swine fever and stay up-to-date about the outbreaks overseas.

Veterinarians

Everyone

  • Keep illegal imports out of Australia.
  • Declare all meat and meat products at airports.

Control

Responding to an outbreak of ASF will be determined by:

  • how early the outbreak is detected
  • the extent of the outbreak
  • location of affected premises
  • virus virulence factors
  • whether feral pigs are involved.

The Australian Veterinary Emergency Plan (AUSVETPLAN) policy, is to control and eradicate the disease in the shortest possible time using a combination of strategies. This will involve:

  • an epidemiological study to establish the potential role of vectors in the transmission of the disease in Australia
  • movement controls to prevent further spread of the virus by animals, people, products and equipment
  • tracing and surveillance to determine the source and extent of infection
  • destruction of all infected and exposed susceptible animals
  • sanitary disposal of destroyed animals and contaminated animal products to remove the source of infection
  • decontamination to eliminate the virus on infected premises and equipment
  • control of the tick vector
  • a public awareness campaign.

Phone 13 25 23 or the Emergency Disease Watch Hotline on 1800 675 888 if you suspect ASF.

Further information