The reservior for Lyme Disease is small ground nesting rodents which are
fed upon by the very youngest ticks.  Then when they are bit larger but
still very tiny these ticks come out and bite something along the line of
at least 30 natural hosts (although they are called deer ticks) and these
early bites are what transmit Lyme Disease.  It is not passed from animal
to animal.  If the dog brought in more of these early instar (life stage)
ticks then it is possible that some of those ticks wandered and ate from
someone else (including you) while still holding the infection and it is
this which passes on the disease.  The mammals and birds on which these
ticks feed do not pose a risk other than being a source of transportation
for young ticks which might not yet have shed all of the disease that
they picked up from the rodents.  I have not heard of the disease being
confirmed in ferrets at this point.
 
See
http://fhl.sonic-weasel.org/browse.php?msg=YG12126
http://listserv.cuny.edu/Scripts/wa.exe?A2=ind0303&L=ferret-search
&P=R24483
http://listserv.cuny.edu/Scripts/wa.exe?A2=ind0303&L=ferret-search
&P=R23698
 
The Critical References in
http://www.ferretcongress.org
may have some more recent data.  You'd need to check.
 
Nipping:
http://www.geocities.com/SoHo/Lofts/1083/probintro.html
[Posted in FML issue 4583]