FeLV Elisa Test

caroleen

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What are the chances of a false negative in the Elisa test? This happened to me. I have read it happened to others. I have had my mother cat tested and she was negative but when I read it makes me wonder is a negative result really a negative result????????????
 

violet

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This article explains how that can happen:
http://www.sheltermedicine.com/porta...ine_felv.shtml

How accurate is the test?

The blood test itself is quite accurate, but not perfect. Because cats can be transiently infected, it is possible that a cat will initially test positive for FeLV, and then recover and test negative at a later date. This is especially likely to occur in otherwise healthy kittens. In most healthy cat populations FeLV is quite uncommon, and this leads to an increase in the relative number of false positive results. In some studies, over half of FeLV positive results obtained by veterinary hospitals from healthy cats were incorrect.

The blood test may also falsely identify recently infected cats as negative. To be absolutely certain, cats must be tested 1-3 months after their last known exposure. False negatives are more common when samples other than blood (e.g. saliva, tears) are used and when multiple samples are pooled.
More info in this article:
http://maxshouse.com/feline_leukemia_virus.htm
 

cc12

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I agree with retesting. Mine have been tested in various environments more than once because of other things and they wanted to make sure.
The test is usually correct but peace of mind goes a long way. It will always be in the back of your mind. This way you get some solid answers.
 

momofmany

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It isn't always that the test has a false positive or false negative. It's the nature of what the Elisa test is looking for and the nature of FeLV. If cats are exposed to FeLV, they'll take the virus into their system and the body tries to fight it off. Elisa tests for exposure to the virus that causes FeLV, not that they actually have the disease. That is why the explanation above says "transiently infected". A cat usually fights off the disease in the first 30-45 days, which is why they suggest that you retest. If a cat hasn't fought it off during that time, it usually remains positive because either a) the virus exposure has turned into real FeLV or b) the cat was exposed again.

Only an IFA test can prove or disprove FeLV. The problem is that most vest are not up to date in their practices and don't run it.
 
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