Greetings,
               My cat has come down with a very unusual and apparently
uncomfortable illness.

Symptoms, symptoms, symptoms;

 Appears to be angry with tail (about hourly, for a few minutes)

  Bouts of aggression against self (tail chasing with growling,
hissing, vocalizing and tail biting).  This behavior worsened gradually
over 5 days, peaked two days ago (cat was insane about it), and now
will settle for less than a minute of it at a time.
 Fits of tail-directed aggression can usually be stopped with several
squirts of water
Hyper Sensitivity.   Rarely will flinch at slightest provocation.
Occassioanally unusually playful (fiesty), like it would love to chase
something.

Pupils usually seem dialated, but other times narrow slits in bright
light.

Have seen yellowish vomit twice.

Reluctanct to eat, but eats sometimes

More reluctant to drink, but drinks occasionally

Warm nose.

Walks slowly but steadily.

Has found a secluded corner in a closet to sleep in.

Never aggresive towards me, only towards it's tail.

Skin seems fairly elastic.  Hair appears slightly raised.  Tail hair
thinned out at tail end from biting.

It's been about 10 days now since he first started in with tail chasing
(fighting with his tail), this behavior grew from a few minutes
every five hours to a few minutes every 20 minutes (two days ago, and
he was quite aggressive about it).
This behavior has subsided to the point that, if left alone, I don't
think he'd chase himself to exhaustion.. but would growl at his tail
and
bit occasionally, as he does within a half hour of waking.    During
the first two days, his nose was cool, and has been warm since.

Refuses to go outside, but sometimes will go out within a few feet of
the door.

No wheezing, sniffling, or any sign of respiratory problem.

Eyes have good color.

He lives in a small apartment complex where there are other cats and
some stray cats.  A few weeks ago I saw him get attacked by a cat
I figured it was a stray and also insane.  It was the pounce, bite, and
run type of attack.. not the all-out battle type.

I have never seen him chase his tail before, or engage in any other
self-mutilation.  He didn't bite his tail raw either, but two days ago
he was having an all-out battle with it.

He can be controlled from biting his tail by squirting water, covering
his tail, or sometimes just talking to him.

He seems to feel like we do when we get the worst case of the flu.
It's hard to say if he is getting better, but it's clear he is not
getting worse regarding tail attacks... that has gotten better.

He never acts scared of me, or other people.  I presume he took to
sleeping in a secluded place because he feels terrible.

I switched his food two days ago from dry low-grade (rendered proteins,
cellulose filler) to dry high-grade (just chicken etc, no parts, no
filler).

Switching his food produced a normal stool.

He has not been biting non-food objects.

This cat seems to be previously owned and abandonded.. and I took it in
as a stray about a year ago.

Except for the tail-biting and being angry with tail, there are no
pronounced behavioral changes other than appearing gloomy (sick).
He seems failry lively sometimes.  Oddly, it seems he feels very
strange when attacking his tail because sometimes after being squirted
several times he comes right over to me and stares at me, like the
comfort of being around were more important than the risk of being
squirted (he only get's squirted if he bites his tail).

I have'nt ruled out rabies, but it doesn't seem very likely.

I suspect this may be distemper.

I don't think it's a spinal tumor, because he has a fever.

He has no trouble walking.

So, for a chance at a free photo of Fluffy (or name your prize).. what
the heck is wrong with my cat?

Thank you !