Message Number: YG5694 | New FHL Archives Search
From: Danee DeVore
Date: 2001-07-22 20:14:00 UTC
Subject: Re: ADV Home Tests From Avecon

--- In Ferret-Health-list@y..., MC <MC@P...> wrote:
> Boy, have I got some questions!

> What really hits me between the eyes is Bancho now showing
negative. I know Judy disagrees with me on this, but I have always
questioned the
> validity of the numerous positive results with the NZ ferrets. I
have contended all along that a genetic marker or some sort of
interaction due to
> the required parvo vaccination in New Zealand was the cause. (Mind
you, I am not a medical person in any way, shape, or form...just me
> guessing..nothing scientific about my feelings)

A discussion of the possible effect of a Parvo vaccine on ADV test
results took place last fall on the ADV List. Here is a cross post
from that list that addresses the question.


Because some of you have been told that a canine distemper vaccine
can cause
a ferret to test positive for ADV, and because it did not seem
logical to me,
I put the question to several of the researchers that are familiar
with ADV
and with the CEP test. What follows is my email with the question,
responses from both Dr. Bruce Williams and Dr. Marshall Bloom.
Although it
is not a definite no, it does indicate that it is not likely.
I hope this information helps.
Dear Good Doctors,
I have sent this to several of you, because I know you are all very
busy, and
my hope is that one of you will have an answer.
The question I have is, can a canine distemper vaccine cause a ferret
to test
positive for ADV with the CEP test? The 3 vets I normally take my
ferrets to
all say they don't think so, but do not know for sure. United
service reps have told people repeatedly that a CD vaccine like
Fervac can
cause a positive CEP test result, for up to 4 months after the
vaccine has
been administered. I would like to get this cleared up once and for
all, and
post the answer out on the ADVList. Many people think that because
ferrets have been recently vaccinated, they can't test for ADV.
Thank you all for your time.
Danee DeVore
Seems to me that a conversation that Marshall and I had a while back
this one. Marshall, didn't you say that distemper vaccination would
cause a positive CIEP test due to different epitopes in the canine
parvovirus 2 fraction of the distemper and the ADV used in the test?

(BTW, it wouldn't be the distemper causing a cross reaction - canine
distemper is a totally different genus of virus - a morbillivirus.)

There is no immunological cross-reaction between ADV and other vaccine
parvoviruses (like mink enteritis, canine parvo, feline panleukopenia
virus). Furthermore, as Bruce notes, ADV is in a different genus and
unrelated to canine distemper.

The question is could distemper or another of these viruses induce a
spurious reaction that would register as a false-positive in CEP.
This is
possible, but it has never been rigorously evaluated. Such a false-
reaction, if it occurs, would likely be short-lived (a couple of
perhaps) because ADV-negative mink farms stay negative even though the
animals are vaccinated.

So, although I am not a DVM, it seems to me there are 2 options.
First, get
a serum sample prior to any vaccination and do a CEP test. Second, if
animal tests positive, retest the animal in a month or so.

Finally, if United has information that addresses this issue, someone
ask them to either publish it or put it in a bulletin.

Hope this is helpful.

Marshall E. Bloom, M.D.
Medical Officer (Research)
Laboratory of Persistent Viral Diseases
Rocky Mountain Laboratories
903 South 4th Street
Hamilton, MT 59840
PH: (406) 363-9275
FAX: (406) 363-9286
e-mail: mbloom@n...

I have a ferret that for a while got both positive and negative
results on CEP tests. Through other tests we have been able to prove
that he definetely does have ADV.
Always remember, no test is infallible. When conflicting results
arise, retest. If you still aren't sure, send samples to the U of
GA, have an electrophoresis done to check the gammaglobulin
percentage, or run other tests. It is dangerous to assume that just
because one test was positive and a later test negative, the ferret
is negative for ADV.