>From:    charlie <[log in to unmask]>
>Subject: what is aleution mink disease?
>Please pardon my ignorance, but what is aleution mink disease?
 
Aleutian mink disease virus, or ADV, is a parvovirus that infects mink,
ferrets, raccoons, skunks and possibly other Mustelidae.  It is in
the family Parvoviridae, subfamily Parvovirinae, genus Parvovirus.
Parvoviruses are widespread in nature.  ADV causes an infectious disease,
known as Aleutians disease, and is shed for months and months.  ADV is a
hardy virus that can live outside of the body for an extremely long period
of time.  In Sweden, ADV was still "live" in mink cages that had been
abandoned for three years.  There is question whether the virus remains
infectious in deceased animals or in the ground where an infected animal
died and decayed.
 
The virus in mink was discovered in the late 1940's and was first thought
to be a genetic defect in the Aleutian genotype mink - hence the name
Aleutian mink disease virus.  Later, it was discovered that all mink could
be infected with ADV.  Plasmacytosis, as AD in ferrets was once called,
dates back to the 1960's.
 
ADV is passed via saliva, feces, urine, and in the placenta.  The State
Veterinary Agency in Sweden concluded that the ADV virus was airborne by
trials done in the Netherlands.  They estimated that the "danger zone" is a
radius of 1-5 km.  If this is true, then the spreading of non-active ADV
can easily be passed between ferrets.  Although, ADV can probably be spread
by airborne route, a more likely means of spread is by contact with
contaminated surfaces, nipping, etc.  ADV positive mink have been housed
next to ADV negative mink for research purposes and have not transmitted
the virus.  In one instance in the US, four ferrets were housed together
and three were tested positive.  Even after four months, the negative
ferret still tested negative.  Some experts think that offspring born of
non-active ADV animals have even less of a chance of being active then
their parents.  For ferrets, it is not known how fast they will test
positive after contacting ADV.  For some "hot" mink strains, there can be
positive reactions after ten days, but sometimes it can be at least a month
or so.
 
Dr. Marshall Bloom from the Rocky Mountain Laboratories has been studying
AD in mink for several years, and he does have knowledge of ADV in ferrets.
He thinks there may be many specific strains of ADV in ferrets.  Different
strains of virus might explain why some clinically healthy animals test
positive for ADV.  Not all mink strains of ADV are very "hot" and they are
just beginning to be able to predict which ones are "hot" based on DNA
sequence.
 
Unfortunately, there is currently no vaccination or treatment for ADV in
mink, ferrets or any other species.  Dr. Bloom and his co-workers at the
Laboratory of Persistent Viral Diseases have demonstrated neutralization of
ADV by antiviral antibody in vitro, which suggests that mink are capable of
making antibodies that can neutralize ADV.  However, to date no one has
demonstrated an effective vaccine.  They have also isolated an infectious
molecular clone of strain ADV-G.  This clone should prove useful in studies
of pathogenesis and immune protection.
[Posted in FML issue 2868]