[Felvtalk] ELISA & IFA Tests:

[Lynda Wilson]

First of all there are two commonly used types of FeLV tests. One is the 
in-office ELISA and the other is the laboratory run IFA test. Both types 
test for the FeLV protein p27. However, they detect the protein in different 
forms and detect infection at different stages. 1.) If a cat or kitten is 
ELISA positive, but healthy, an IFA test should be performed. Here is where 
the confusion begins.

If the cat is IFA negative but ELISA positive there are two possibilities. 
One is a false positive ELISA test and the other is a stage of the disease 
is present at which the IFA test doesn't detect infection. Therefore the 
suspect cat or kitten should be isolated and retested in at least 6 weeks. 
If, at that time the cat is IFA positive, you know that the cat if infected. 
The IFA is 99% accurate. An IFA positive cat can be shedding virus and 
infect other cats and kittens."

Remember to retest 6 weeks after an ELISA positive result, the cat's immune 
system can clear the virus especially in an adult cat (kittens and seniors 
have the most difficulty clearing the virus).


This is what I have always been told by veterinarians and everyone on this 
FeLV thread. I have not heard any different. This info is true!


Lynda