Yes, even after the symptoms are gone the infected ferrets can infect
others.

Use these refs:

http://web.archive.org/web/20000816025122/http://www.afip.org/ferrets/ECE/ECE.html

http://ferrethealth.org/archive/FHL14634

I've been told that at some other locations people who are writing what
sounds like claptrap don't realize the need for quarantining of ECE
infected and ECE exposed ferrets. Given how very many reputable refs
there are I just do not understand why people don't look things up
and learn. (Sorry, too hard a day for breathing so I am grumpy.)

It is always best to avoid situations that can create exposure.

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/
http://www.ferretcongress.org/
http://www.trifl.org/index.shtml
http://homepage.mac.com/sukie/sukiesferretlinks.html
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)

[Posted in FML 7480]