Pet Factsheets

Client Factsheets > Cattle > Malignant catarrhal fever

< Back to search

CONTRIBUTOR(S): Vetstream Ltd, Paul Wood,

Malignant catarrhal fever

Malignant catarrhal fever

MCF is a relatively rare, sporadic disease in the UK affecting cattle and deer. Outbreaks can occur, but usually only a single case is seen.


Malignant catarrhal fever: ophthalmic symptoms
©Peter Jackson

What is MCF?

In the UK, it is caused by ovine herpesvirus-2 (OHV-2) and sheep are the reservoir for infection in cattle. In Africa, the disease is caused by Alcelaphine herpesvirus-1 (AlHV-1) and wildebeest are the reservoir for infection in cattle.

The primary symptoms of the disease are depression, anorexia (off food) and fever (40.5-41.5°C/104.9-106.7°F).

Other signs include:

  • Red, swollen, cloudy and painful eyes; both eyes are affected.
  • Blindness.
  • Painful, ulcerated mouth and muzzle; the animal may hypersalivate (drool).
  • Profuse discharge from the nose and eyes, which may cause noisy breathing.
  • Generalized superficial lymph node enlargement (swellings over the body).
  • Nervous signs may include muscle tremors, hypersensitivity to noise and stimulation, incoordination, head pressing and convulsions.
  • Skin and teat lesions may occasionally be seen.
  • Diarrhea.

MCF can present in a similar way to diseases such as infectious bovine rhinotracheitis (IBR), bovine viral diarrhea (BVD), blue tongue, vesicular stomatitis and foot and mouth disease, so it is important to consult with your veterinarian as soon as possible.

How is MCF diagnosed?

Your veterinarian will diagnose MCF based on a history of sheep or wildebeest contact and characteristic clinical signs.

An antibody ELISA test is available, however this test can result in false negatives, as the disease can come on so quickly that animals do not have time to produce the antibodies that this test detects.

A PCR test can be conducted on blood, to detect the virus directly, but results may take 7-10 days, so results may come through after the animal has succumbed or been euthanased.

How has my animal(s) become infected?

Contact with sheep or goats (especially around lambing) seems to be necessary for transmission of the disease to cattle, but the route of transmission is unknown.

Cases of MCF may occur months after contact with sheep, suggesting prolonged incubation or latent infection. The virus is very fragile and will not survive for more than a day outside the host, so it will not survive in bedding or on pastures.

Cattle and wildebeest are considered to be ‘dead-end’ hosts and are not thought to transmit MCF to other cattle.

Can MCF be treated?

Affected animals should be euthanased on welfare grounds. If left untreated, then the natural mortality rate in acute cases is close to 100% within 5-10 days of the onset of clinical signs. Affected animals really suffer and so prompt euthanasia is the kindest option. With intensive supportive treatment, a minority of MCF cases may survive the acute disease to either recover or become chronic cases. However, chronic cases often relapse.

How can I prevent MCF in my herd?

Avoid cattle being in contact with sheep.

There is no vaccination available.

Can MCF affect people?

No!

Scroll to top