Influenza vaccines: I'm not a vet but from what I have read they killed
virus vaccinations so no contagion risk.  See CDC resources such as:
http://www.cdc.gov/ncidod/diseases/flu/fluvac.htm
and
http://www.cdc.gov/nip/Flu/default.htm
 
Rhea, it can be hard to spot pneumonia in them until it is too late.
Meeteetse was someone who just never coughed and one day years ago she
had an intermittent tiny cough so we took her in to the vet that very
day.  Because it was an emergency appointment we couldn't have our ferret
vet who was in a different appointment.  Well, the vet listened and heard
nothing wrong, but coughing was unlike her and she had also done her "I
am sick, Mommy" thing that day where she would gently take one of my
big toes into her mouth, so we had a chest x-ray done.  She had serious
pneumonia and pleurosy.  This was a very dangerously ill little girl.
Anyway, my point is that ferrets CAN have a very bad lung infection and
show almost no symptoms at all till their very lives are in danger.  (As
you can guess, like you we take coughing seriously in our house, even
more so since then.)
 
BTW, I personally doubt the bath had anything to do with it, though I'm
not a vet.
 
Anonymous, 3 years old is not too young for adrenal growths to happen
though certainly it's better that they not happen that young, but when
only the tail is involved it is more likely to be only a dermal problem.
Look up "rat tail" in the FML Archives and you will find many solutions.
The FML Archives addy is very easy to find: just always remember that it
is in every day's header of the FML.
 
Gary: Yes, they scent mark.
 
"Love bites": if you mean do grooming nips, yes, they do that.
[Posted in FML issue 4307]