Encephalomyocarditis virus

Description

Encephalomyocarditis (EMC) is caused by Cardioviruses in the family Picornaviridae. EMCV, while considered a rodent virus, may infect a wide range of mammals including non-human primates, elephants, pigs and humans. Outbreaks of disease due to EMCV infection have been most frequently reported in pigs and wildlife species held in captivity. EMCV is shed in the faeces and urine of rodents, which contaminates food and water supplies of other mammals. Outbreaks of disease are usually associated with severe infestations of mice and, less commonly, rats.

Affected pigs typically present with a history of sudden death from cardiac insufficiency and cardiogenic pulmonary oedema. Other clinical signs may include fever, anorexia, lethargy, dyspnoea, trembling, staggering and paralysis. Mortality is higher in suckling pigs compared with older pigs. EMC viruses can cross the placenta in pigs and cause abortions, stillbirths and mummification.

Diagnosis and tests available

Diagnosis

Diagnosis is based on a combination of history, clinical signs, serology and histopathology.

Tests available

Test

Sample(s) required

Days of the week test is conducted

Turnaround time1

Encephalomyocarditis Virus Real Time PCR

Fresh tissue

According to demand

2-3 working days

Encephalomyocarditis Virus Isolation

Fresh tissue

According to demand

3-4 weeks

Encephalomyocarditis VNT

Clotted blood (red top tube)

Batch tested weekly according to demand

1-2 weeks

Histopathology examination

Fixed tissue

Monday – Friday

Up to 2 weeks for brain samples. Up to 5 days for all other sample types.

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 the dam of affected litters
    • Collected into a plain red top tube
    • Submit chilled

Fixed tissue

  • Brain and spinal cord and sections of heart, liver, kidney, lung, spleen
    • Submit fixed in neutral buffered formalin at a 10:1 ratio of formalin: tissue

Fresh tissue

  • Fresh heart, brain,lung and spleen tissue collected separately and aseptically from a recently deceased animal
    • Submit chilled

Note

Most infections are subclinical and EMC viruses have rarely been recognised as a cause of human illness.