Yes, Coccidia could be confused with ECE (epizootic catarrhal enteritis)
but a simple fecal exam from your vet will quickly tell you what your
ferret is dealing with.  Cocciddia stools are generaly more liquid and
not well-formed.  The color usually stays in the "brown" cateragory.
ECE is alot more "expressive".  ECE poop is often a dark, shiny, smelly
projectile kinda poop that sails 2-3 feet outside of your ferret's cage
corner.  Neon green - bright camo green are the usual tints.  The
symptoms are similar- dehydraytion, lethargy, loss of appeitite.  The
treatments are VERY different.  ECE is believed to be a corona virus,
while coccidia needs to be treated as a parasite.  Do your vet and your
ferret a favor- take them a lovely sample of any poop in question.
They'll love you for it.  Hope all goes well.
 
Hugs & Dooks,
Marlene b. / RFRL
[Posted in FML issue 4557]