Temporary bluetongue virus zone change for Victoria

Part of northern Victoria has been designated as a bluetongue virus (BTV) zone for the next 30 days, after evidence of past exposure to the virus was detected in several 12 month old dairy heifers.

Situated near Echuca, the zone, which consists of a Zone of Possible Transmission of 50 km and a further Buffer Zone of 50 km, around the property of detection, will remain in place whilst surveillance activities are undertaken.

Whilst BTV is endemic in northern Australia, Victoria, along with the rest of southern Australia, has previously been classified as being free of BTV. This has provided the live export sector with access to overseas markets requiring assurance of BTV freedom.

Under the changes, cattle and other livestock species situated in the zone will not comply with import conditions of countries requiring assurance of area freedom from BTV.

There are no changes to conditions for moving cattle from this zone to other parts of Victoria, or elsewhere in Australia.

Victoria’s Chief Veterinary Officer Dr Charles Milne said Agriculture Victoria would undertake surveillance in cattle herds to inform the longer term BTV status of the area.

“The purpose of the surveillance is to identify the potential source of the virus and determine if local spread of this insect-borne disease has occurred,” Dr Milne said.

“Agriculture Victoria staff will be contacting producers in the area to seek their assistance and make arrangements for on-farm sampling of cattle.

“Both the zone and surveillance activities are essential for providing assurances to our international trading partners, and supporting Victoria’s, and Australia’s, valuable live animal export industry.”

Routine pre-export testing initially found antibodies in the animals’ blood, which was subsequently confirmed by CSIRO’s Australian Animal Health Laboratory.

The detection of antibodies indicates previous exposure to BTV. The cattle were not showing signs of clinical bluetongue disease and no virus was detected in the animals’ blood. Clinical bluetongue disease has not been recorded in any livestock species in the field in Australia, with the exception of two minor incidents in sheep in Darwin in 1989 and 2001.

Bluetongue is a viral disease of livestock spread by flying insects known as midges. All ruminants are susceptible, including cattle, sheep, goats, buffalo, camelids and deer. BTV does not spread rapidly, as it is not spread directly from animal to animal.

There is no risk to humans from BTV, nor is there any food safety issue associated with livestock products.

Source: Agriculture Victoria