Cat - Feline Virus Tests

(Please see more detailed handouts on FeLV, FIV, FIP and Vaccination.)

Virology today provides us with the means to test for many viruses affecting both us and our pets.  These techniques are particularly useful in the cat since there are several serious viral infections of felines that can result in immune related problems.

Which feline viruses do we commonly test for?

Tests are available for many viruses causing disease in cats. Common feline viral tests are available for the Feline leukaemia virus (FeLV), Feline immunodeficiency virus (FIV), Feline coronovirus (FCoV) and also Feline viral enteritis.  Feline enteritis is confusingly also known as panleucopaenia, Feline parvovirus, Feline infectious enteritis and was once a major killer disease.  Today the virus can still be a problem, particularly with young kittens in rescue centres.

What are the diseases associated with these viruses?

1. Feline leukaemia virus (FeLV) is responsible for a number of diseases in cats including  leukaemia.  It is highly contagious and is transmitted through body fluids, eg mutual grooming, and across the placenta in pregnancy.
2. Feline immunodeficiency virus (FIV) is often known as feline AIDS.  It inhibits the cat's immune system, preventing a protective response to other infectious agents.  FIV is highly contagious and can be transmitted via the placenta, but the main cause of spread is as a result of cat fights (bites and scratches).
3. Feline infectious peritonitis (FIP) is caused by a mutation of Feline coronovirus.  FIP is an immune related disease and often results in the production of fluid in the abdomen and chest cavities.  It is transmitted through infected body fluids and via the faeces.
4. Feline paneucopaenia (Feline enteritis) was the first feline viral disease discovered. The causative agent was subsequently shown to be a parvovirus, very similar to the canine parvovirus.  It requires rapidly dividing cells in order to multiply and therefore can present problems with unborn kittens resulting in death or partial paralysis due to neurological deficits.

Why is testing for these viruses important?

FeLV and FIV are implicated in a wide variety of diseases including those involved with bone marrow and immune dysfunction.  Therefore testing for these diseases is a routine procedure for the sick cat, particularly if the cat has been in contact with others of unknown FeLV or FIV status.  Similarly, testing is prudent if a new cat is intended to be introduced into a household with other cats.

Feline coronoviruses are common and found in the intestinal tract of many healthy cats.  The strain of FCoV that causes FIP is less frequently found.  At present there is no specific test that will detect the FCoV mutant virus that causes FIP.   The number of cats in the population that carry antibodies to FCoV is high.  Therefore, testing cats for FCoV is usually restricted to those for which a diagnosis of FIP is strongly suspected due to clinical signs and other supporting laboratory tests.

The tests all involve taking a small blood sample which is tested for either the virus itself or for antibodies to the virus.  Once we have the results we may advise further tests before confirming whether the cat is infected or not.

Summary

Tests for FeLV and FIV are useful screening tests and are routinely carried out in general practice.   For confirmation of the results further samples may be required.

FIP is not uncommon.  There is not a specific test for the FCoV mutant causing FIP at present.  Testing for coronovirus in general is frequently carried out in order to support a diagnosis based on clinical signs.

Testing for feline panleucopaenia (feline enteritis) is very useful in the case of kittens and cats in or obtained from rescue centres.

Please contact us if we can help further.