Menangle virus infection

Description

Menangle virus infection is casued by (a paramyxovirus) and was first recognised when it caused a single outbreak of reproductive disease in pigs in a large piggery near Sydney in 1997. A control program, successfully managed by NSW Department of Primary Industries, subsequently eradicated the virus from the piggery. A large serological survey failed to find any evidence of infection in other Australian pigs. No further outbreaks of the disease have occurred to date.

Flying foxes (fruit bats) near the piggery had antibodies to the Menangle virus. It is believed that flying foxes are the natural host of the virus, and that it was a relatively rare event that led to the virus 'jumping' into pigs.

Clinical signs include a severe decline in farrowing rate, a high incidence of delayed returns to service, and a marked increase in the number of mummified and stillborn piglets, some with severe deformities (e.g. arthrogryposis, brachygnathia, kyphosis, porencephaly and hydranencephaly). Stillborn piglets may have a severe non-suppurative encephalomyelitis.

Diagnosis and tests available

Diagnosis

Diagnosis is based on history, gross pathology, histopathology, virus isolation and virus neutralisation test results.

Tests available

Test

Sample(s) required

Days of the week test is conducted

Turnaround time1

Histopathology examination

Fixed tissue

Monday – Friday

Up to 5 days

Menangle virus neutralisation test

Clotted blood (red top tube)

According to demand

1-2 weeks

Menangle virus isolation

Fresh tissue

According to demand

3-4 weeks

1 Turnaround times are provided as a guide only. For specific information about your submission please contact Customer Service.

Specimen requirements

Blood (without anti-coagulant)

  • 10 ml of blood from farrowing sows with affected litters collected into a plain red top tube
    • Submit chilled

Fixed tissue

  • Fixed tissues from foetuses (whole brain and spinal cord)
    • Submit fixed in neutral buffered formalin at a 10:1 ratio of formalin: tissue

Fresh tissue

  • Whole mummified or stillborn piglets
  • Fresh tissues from aborted foetuses (brain, lung and heart)
    • Submit chilled