Obviously, if fecal matter on shoes dries on the outside but not the
inside then the virus can stay viable even longer because it stays
moist so the fatty envelope around the virus lasts longer.

Here are some expert references showing that bringing in Canine
Distemper on shoes is NOT a myth:

From
http://www.veterinarypartner.com/Content.plx?A=1733&S=0&EVetID=3001640

QUOTE
The distemper virus consists of a single strand of RNA, encased in a
protein coat which is again encased in a fatty envelope. This sounds
esoteric but the fatty envelope makes all the difference in the world.
The fatty envelope is easily disrupted in th e environment which makes
it impossible for infectious virus to persist in the environment.
Because an intact fatty envelope is required for infection, virus
transmission must involve dog to dog contact or at least contact with
extremely fresh (less than 30 minutes old at 60 degrees and up to 3
hours oldat room temperature) infected body secretions. As with other
viruses, living virus happily freezes and can survive for years if
kept frozen and protected from light. Routine disinfection and
cleaning readily kills the distemper virus in the kennel setting.
END QUOTE

Back when I wrote
http://pets.groups.yahoo.com/group/ferrethealth/message/7081

There were some refs that existed then which are not accessible to
me now, but it has useful quotes in it for those who need more info
on this topic but here is what those refs included at that time:

BEGIN QUOTED SECTION OF MY PAST POST:

Here are some resources:

http://www.marvistavet.com/html/body_canine_distemper.html
which includes
>The distemper virus consists of a single strand of RNA, encased in a
>protein coat which is again encased in a fatty envelope. This sounds
>esoteric but the fatty envelope makes all the difference in the world.
>The fatty envelope is easily disrupted in the environment which makes
>it impossible for infectious virus to persist in the environment.
>Because an intact fatty envelope is required for infection, virus
>transmission must involve dog to dog contact or at least contact
>with extremely fresh (less than 30 minutes old) infected body
>secretions. As with other viruses, living virus happily freezes
>and can survive for years if kept frozen and protected from light.
>Routine disinfection and cleaning readily kills the distemper virus
>in the kennel setting.
 and
>The infected dog typically infects other dogs via coughing infected
>respiratory secretions though the virus is shed in most other body
>secretions including urine.

http://www.animalhealthchannel.com/distemper/index.shtml
includes
>Transmission
>Infected dogs shed the virus through bodily secretions and
>excretions, especially respiratory secretions. The primary mode of
>transmission is airborne viral particles that dogs breathe in. Dogs
>in recovery may continue to shed the virus for several weeks after
>symptoms disappear, but they no longer shed the virus once they are
>fully recovered.
>
>It is possible for humans to contract an asymptomatic (subclinical)
>CDV infection. Anyone who has been immunized against measles (a
>related virus) is protected against CDV as well.

http://www.michigan.gov/dnr/0,1607,7-153-10370_12150_12220-26505--,00.html
includes
>Canine distemper is a highly contagious disease of carnivores caused
>by a paramyxovirus. The virus is widespread and mortality in juveniles
>is higher than in adults. The canine distemper virus is very resistant
>to cold and the majority of distemper cases in domestic dogs are seen
>in the fall and winter. In wild animals, since the juveniles are more
>susceptible to infection, the majority of cases are seen in the spring
>and summer, but cases are observed year round.
>
>Transmission
>Transmission occurs via an aerosol-droplet route, direct contact, or
>possibly by contact with contaminated objects. It is uncertain whether
>carrier or unapparent infections exist. The virus is shed in the
>feces and urine of infected individuals and some evidence exists for
>transplacental transmission. The usual route of infection is through
>the upper respiratory tract, following inhalation of infective virus.
>Occasionally infection occurs from ingestion of infective material.
>Following entry into the upper respiratory tract, the virus is spread
>to the tonsils and lymph nodes, where viral replication occurs.

http://www.sheltermedicine.com/portal/is_canine_distempervirus.shtml
includes
>Transmission and control
>Canine distemper virus is shed in all body secretions of acutely
>infected animals. It can be spread by direct contact, by aerosol or
>respiratory droplet exposure. Although the virus does not survive long
>in the environment, it can be transmitted by fomites such as hands,
>feet, or instruments over a short time/distance. Virus can be shed by
>subclinically or mildly infected animals; such animals probably play
>an important role in maintaining the virus in a chronically infected
>shelter population. Therefore, careful isolation of all dogs with
>upper respiratory signs -always a good idea- is especially important
>in a shelter where distemper is a concern.
 and
>Distemper survives no more than a few hours at room temperature.
>Cold and moist conditions increase survival, and it can last for
>several weeks at near freezing temperatures. The virus is readily
>inactivated by most commonly used disinfectants. Routine hygienic
>precautions are generally adequate to prevent spread.The most
>important factor in shelter decontamination is quarantine/removal
>of incubating and mildly/subclinically affected animals.

END SECTION

On whether ferrets can get Feline panleukopenia virus (FPV) (also known
as Feline infectious enteritis, Feline distemper, feline ataxia, or cat
plague): from the refs I was able to check there are no actual articles
showing ferrets getting this and it would have been written about if
actual pathology showed it, but there are some vet refs saying that
some other vets claim to have seen it rarely. This means it may be
nothing more rumor or guesswork (which may be right or wrong). From the
result in an old study with one mink which had repeated injection of
the virus, infection by ferrets with FPV MIGHT be possible in very rare
instances under very extreme circumstances, for example, perhaps with a
lot of exposure combined with extreme immune suppression.

http://www.ncbi.nlm.nih.gov/pubmed/2823648

QUOTE

Am J Vet Res. 1987 Oct;48(10):1429-35.
Comparisons of feline panleukopenia virus, canine parvovirus, raccoon
parvovirus, and mink enteritis virus and their pathogenicity for mink
and ferrets.

Parrish CR, Leathers CW, Pearson R, Gorham JR.

Source
James A. Baker Institute for Animal Health, New York State College of
Veterinary Medicine, Cornell University, Ithaca 14853.

Abstract
Parvoviruses from mink (mink enteritis virus [MEV]), cats (feline
panleukopenia virus [FPV]), raccoons (raccoon parvovirus [RPV]), and
dogs (canine parvovirus [CPV]) were compared. Restriction enzyme
analysis of the viral replicative-form DNA revealed no consistent
differences between FPV and RPV isolates, but CPV and MEV isolates
could be distinguished readily from other virus types. Feline
panleukopenia virus, RPV, and MEV, but not CPV, replicated to
high titers in mink. However, on the first passage, disease and
microscopic lesions were observed only in mink inoculated with MEV.
Felinepanleukopenia virus and RPV isolates replicated in ferrets, but
disease or microscopic lesions were not observed. Felinepanleukopenia
virus and RPV isolates could be passaged repeatedly in mink and
ferrets. Virulence of FPV and RPV isolates was low compared with that
of MEV, and only a single mink inoculated with FPV or with RPV
developed clinical disease on the sixth passage of virus.
PMID: 2823648 [PubMed - indexed for MEDLINE]

END QUOTE

also possibly useful:

http://bakerinstitute.vet.cornell.edu/animalhealth/page.php?id=1088

http://jvi.asm.org/content/81/8/4158.long
or
http://jvi.asm.org/content/81/8/4158.full.pdf

which is Journal of Virology, 2007
Canine Distemper Virus Infection Requires Cholesterol in the Viral
Envelope
 - Heidi Imhoff 1, 
 - Veronika von Messling 2, 
 - Georg Herrler 1, and
 - Ludwig Haas 1,*

Abstract QUOTE:

Cholesterol is known to play an important role in stabilizing
particular cellular membrane structures, so-called lipid or membrane
rafts. For several viruses, a dependence on cholesterol for virus
entry and/or morphogenesis has been shown. Using flow cytometry and
fluorescence microscopy, we demonstrate that infection of cells by
canine distemper virus (CDV) was not impaired after cellular
cholesterol had been depleted by the drug methyl-beta-cyclodextrin.
This effect was independent of the multiplicity of infection and the
cellular receptor used for infection. However, cholesterol depletion of
the viral envelope significantly reduced CDV infectivity. Replenishment
by addition of exogenous cholesterol restored infectivity up to 80%.
Thus, we conclude that CDV entry is dependent on cholesterol in the
viral envelope. Furthermore, reduced syncytium formation was observed
when the cells were cholesterol depleted during the course of the
infection. This may be related to the observation that CDV envelope
proteins H and F partitioned into cellular detergent-resistant
membranes. Therefore, a role for lipid rafts during virus assembly
and release as well is suggested.

END QUOTE

Use this to supplement the information I sent to the FML yesterday.
Those only on the FHL can supplement by using the Yahoo site and
separate site archives as well as PubMed for refs like how sufficient
Vitamin A intake protects ferrets from distemper and helps them fight
it somewhat better:

http://jn.nutrition.org/content/137/8/1916.long

Sukie (not a vet)  Ferrets make the world a game.

Recommended ferret health links:
http://pets.groups.yahoo.com/group/ferrethealth/
http://ferrethealth.org/archive/
http://www.miamiferret.org/
http://www.ferrethealth.msu.edu/
all ferret topics:
http://listserv.ferretmailinglist.org/archives/ferret-search.html

"All hail the procrastinators for they shall rule the world tomorrow."
(2010, Steve Crandall)

A nation is as free as the least within it.

[Posted in FML 7830]