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New Discovery Lyme Disease= Aggression

May 31st, 2004, 07:05 PM
I was emailed this article and thought some of you may find it interesting.

This is worth passing along...found on one of the online boards I visit:

We recently had a very strange event that I think
we should share around the rescue community:

Young (~2 years) male, a Lab mix, came into our
program with a "questionable" background. He may
have been aggressive toward some children, maybe
not. We kept him for a good long while --
months of fostering in our premier foster home,
with no problem -- and placed him carefully, with
a single mid-age man who absolutely adored him.
We also, as we do with all our dogs, tested him
for Lyme. He had it; we treated it; case closed
-- we thought.

Everything went very well after adoption -- he
was the star of his obedience classes, a frequent
alumni visitor to our clinics - for over a year.
And truly adored by his adopter.

Then, over a year after placement, Mojo became
suddenly, erratically, and seriously aggressive:
literally attacked visitors to the home, people
at the vet's waiting room, etc. Terrifying. Very
sudden. Totally inexplicable. He was returned
to us with genuine heartbreak from a very loving

Mojo then went to our regular vets and was a
totally different dog: bared teeth and growling
to anyone who approached his kennel, lunging at
other dogs when being walked, etc. We figured
that whatever was happening with him, he had
become unplaceable and started a TDC (Tough
Decisions Committee - something we "convene" and
that is open to anyone with an interest in the
dog when we think that euthanasia might be an

However, someone at the vet's office said that
perhaps we should test him for Lyme. Huh????????
They had had a regular client of theirs come in
recently with similar, out of the blue
aggression, and it turned out that was the
problem - puzzled them, but seemed to be the
case. Okay -- hey, we'll try anything -- so we
had him tested. He was high positive! Fine, we
started treatment while we continued to figure
out what to do with him via the TDC.

Almost immediately, however, once the antibiotics
were begun, the Mojo we knew came back! He was
himself again -- bouncy, happy, a bit neurotic,
but not at *all* aggressive! The staff at the
vet's was amazed, but all confirmed this change.

We didn't believe it; and the veterinarians
didn't believe it .... BUT a thorough search of
the internet turned up a number of studies and
anecdotal observations indicating that in some
dogs (and in some humans)! the primary symptom
of their Lime Disease can be sudden, irrational
and serious aggression.

Well, we've known for a while to check the
thyroid levels of dogs that show aggression that
just "doesn't fit". Now we have added testing
for Lyme as well. And we have -- results not
yet in -- another dog that we placed over a year
ago who has been returned because of
out-of-the-blue aggression ... and he has also
tested high positive for Lyme! We've started
treatment and will be monitoring his response.

So --- plug this in to your protocols. It's
worth checking out. I spent the day today with
Mojo ... and he truly is just the same dog we
placed over a year ago. (We've let his original
adopter know -- because he vowed that it had to
be *something* causing this behavior. But he
cannot take Mojo back because his roommate, one
of the people attacked, won't even consider it.
For the record, there were no skin-breaking
contacts in any of these attacks, but plenty of
fear and we consider them as serious as if they
were full-fledged bites.)

We actually have additional insight into this
because one of our volunteers (human) has had
Lyme Disease. Took many months for her to be
diagnosed, and once she was, she learned that
it's a VERY nasty bug that really remains around
permanently, waiting for a chance to "crop up"
again. When we place Mojo again (and our TDC
unanimously agrees that we should do this), we're
going to explain the background, these amazing
events, and require that the adopters have him
tested every six months, whether or not he's
showing symptoms. We have no idea whether that
will work or be sufficient -- we're rather flying
blind in this -- but it seems a rational

I'll post again if we learn more from the second
dog (also a Lab mix). But based on what we know
now, it is a real possibility: Lyme *can*, in a
few rare cases, cause aggression, aggression that
can be reversed.

May 31st, 2004, 08:48 PM
Pfffhht! I don't buy it. We have Lyme disease here too and bad labs, Affectionately called "face eaters"....once confined away from their normal surroundings these dogs act wild and it is something we expect at times...except when it is your face being chewed like a soggy rawhide..
Not ALL labs are like this, please do not get me wrong, But this is the only breed I have seen so docile as a lamb with their family and when it's time for a simple procedure behind closed doors OUT comes Cudjo for the face...
Face eaters..I'm just saying.....Labs are great dogs but there are a few I would like to forget...*Note: Never a victim but had to fight to save a co worker many times..

May 31st, 2004, 09:40 PM
I have to agree with Karin.

Of all the research I have done on dogs and Lyme Disease,nothing was said about aggression at all.And it would have been mentioned.

Here is a link that ells you the signs of Lyme Disease in dogs.

May 31st, 2004, 11:21 PM
Well folks I wouldn't discount it...and why? Because illness can make a dog aggressive because they're irritable and don't feel well.

Lyme disease can cause so many problems with a dog or person if I had it I would probably bite someone myself.