To the FML -
 
Recently there has been a lot of talk about the veracity of the CIEP test
available through United Vaccines, about whether there is a high incidence
of false positives - animals that will give a positive test for reasons
other than possessing antibodies to the ADV virus.  Most of the discussion
centers around animals who have been vaccinated against other diseases.
 
Let me first say that I do not consider myself the last word on this test,
but Dr. Marshall Bloom, who may be the most widely published scientist in
the area of ADV (and who helped to design the CIEP test), IS.
 
The main question regarding the test is that whether animals who have
been prviously vaccinated against canine distemper or canine parvovirus
(a common ingredient in dog distemper vaccines) or other subcomponents
of that vaccine would test positively for ADV antibodies.  Dr. Bloom does
not believe that this is a problem, and has never seen this phenomenon.
Indeed, all of his experimental animals (mink)are vaccinated against mink
enteritis (another parvovirus) and canine distemper, and they don't cross
react on the CIEP test.
 
I think a lot of this "false positive" assumption comes from a number of
sources - positive reactors that have ADV but die early of other causes,
so are termed "not having the disease", other parties developing competing
tests (there are several groups who are in development right now), and a
natural desire for hope, however small.  Several years ago, people were
posting on the Internet about being able to cure distemper by injecting
serum from vaccinated animals into affected animals - 1 cc
intraperitoneally.  I am all for hope, but not when it puts others at risk.
 
Marshall Bloom is still the expert on this question, and he does not
believe that false positives, if the test is run correctly, exist.  Until
someone can back that up with some real data, I've got to go with his
experience.  (However, I'd love to see any data to the contrary - if United
Vaccines or any other group is saying that there are false positives, I'm
hoping they'll share some data with us...)
 
What actually concerns me more at this point is the possibility of false
negatives.  Even in the hands of an expert, this test may have 3% false
negatives (that's published and in mink) - animals that do not react for
some reason or another.  But that's another story, and one that has yet
to be worked out.
 
Last weekend Colleen and I adopted two ferrets - you can bet I'll be
testing for Aleutian Disease this time around.
 
With kindest regards,
Bruce Williams, DVM, DACVP
[Posted in FML issue 3222]