Infectious Diseases of Dogs
Canine Influenza
Leptospirosis (zoonotic)
Rabies transmission
Rabies -possible infection from pet
HIV AIDS -
can dogs and cats get infected
Distemper possible
Possible distemper
Giardia
also see Giardia
also see Zoonotic
Disease
also see Bacterial Infection
also see Brucellosis
Also see Fungal Infection
also see Herpes Virus
also see Distemper
also see Parvovirus
Canine Influenza
Canine influenza has been in the
news lately. At the present time this appears to be an adaptation of equine
influenza that can infect dogs and spread from one dog to another. It has been
seen in Florida, Wisconsin and New York, so the odds are good that it has spread
widely in the U.S. at this time or that it will soon. In most dogs it is a mild
upper respiratory virus that may be associated with a fever and nasal discharge.
In more severely affected dogs there can be high fevers and signs of pneumonia,
such as difficulty breathing. Canine influenza can be fatal. The current
estimate is that 1 to 5% of dogs infected with canine influenza virus will die
from complications of the infection.
In as situation somewhat similar
to cats with upper respiratory viral infections there is a need to use
antibiotic therapy when dogs have influenza virus. Even though antibiotics do
not kill viruses or even weaken them in most cases, certain viruses are more
likely to be accompanied by secondary bacterial infections. This is especially
true of infections affecting the upper respiratory system. So if your vet
suspects canine influenza it is likely that antibiotics will be administered
even though this is a viral infection rather than a bacterial infection.
This infection is a low risk to
individual dogs in private households but is a bigger risk where dogs
congregate, such as dog shows, shelters and kennels. There is no preventative
vaccine at the present time but it is likely that vaccine companies are already
hard at work coming up with a vaccine. Treatment is supportive since antiviral
medications have not been widely used in dogs and it is not known if they would
be helpful or harmful. It is unusual for influenza virus to jump from one
species to another and then to be contagious among members of the new species.
This is the scenario that worries human public health officials over bird flu
but there is no evidence currently of any risk to people from this new canine
influenza outbreak.
Most dogs suspected of having
influenza at the present time will turn out to have something else, such as
Bordetella infections ( one cause of kennel cough). Despite this it is
worthwhile to keep in mind the possibility that this viral infection may be
present and to keep your dog home from obedience classes, kennels or other areas
that dogs congregate until your dog is completely recovered. This may take
several days.
If you have the need to confirm
this infection it is possible to test for this virus. Cornell University’s
diagnostic lab has testing information. The URL for their site is http://www.diaglab.vet.cornell.edu/news.asp
Dr Mike Richards, DVM
11/15/2005
The AVMA updates their
Canine influenza page as the CDC and Cornell provide data as the Flu spreads
and is confirmed in different states. Please check that page for the latest
updates as well.
http://www.avma.org/public_health/influenza/canine_guidelines.asp
Leptospirosis (zoonotic)
Question: I don't understand what Leptospirosis is
so this article is not clear for me. Can you
tell me what it is?
Fort Dodge Animal Health has updated its Duramune line of vaccines
to
include the serovars (types) of leptospirosis that have been
incriminated
in most of the recent outbreaks. If you live in an area in which
leptospirosis is a concern (the latest outbreaks were on Long
Island and in
California), it would be worthwhile to ask your vet if vaccination
with
these new vaccines would be prudent. These vaccines are
manufactured using
"sub-unit" technology that should help reduce reactions to the
vaccines,
which has previously been a problem with leptospirosis vaccinations.
The
two serovars added to the vaccine are grippotyphosa and pomona.
Answer: Your question is a good one. In one of the older issues
of the VetInfo Digest, available in the
subscriber area (October 1998), this article explains leptospirosis:
Leptospirosis
Leptospirosis is a hot topic at dog shows and other competitions now.
There has been an epidemic of
leptospirosis in Long Island, NY now for a couple of years. It seems
like there is an upward trend in
the number of diagnosed cases across the country, although that isn’t
certain since no one really keeps
statistics on the number of cases of diseases in dogs and cats. This
has occurred concurrently with
recognition among veterinarians that leptospirosis is the portion of
the combined canine vaccines that
is most likely to cause reactions. So many vets are not vaccinating
for this disease. That sounds pretty
bad but the new cases of leptospirosis being reported are from Leptospirosis
species that the vaccines do not protect against. At present there is no
vaccine for the two strains causing most of the current problems, L.
grippotyhosa and L. pomona. A third type (serovar) of Leptospira, L.
bratislava is reported to be on
the rise as well.
Leptospirosis is a water-borne bacteria. It is spread most commonly
by contamination of water
sources by infected urine of wildlife and domestic animals. It can
live in the environment long enough
to spread effectively. Leptospirosis is most commonly associated with
kidney disease but some of the strains of the organism can cause liver
damage, induce bleeding disorders, cause neurologic signs or uveitis (eye
inflammation).
Leptospirosis is difficult to diagnose with certainty because the organism
doesn’t grow well in cultures.
Serum titers are useful in making a diagnosis but it often takes paired
samples to demonstrate a rise in
titer. In the meantime, it is important to treat for the organism to
try to limit the damage that it does.
Leptospirosis organisms are susceptible to penicillins, which should
be used for at least two weeks if
infection is suspected. It is also important to treat for any damage
that is occurring to organs and to
control any developing bleeding disorders. Kidney damage and bleeding
disorders often require very
aggressive treatment in order to achieve a successful outcome so this
is a situation in which long-term
hospitalization may be appropriate and necessary.
Leptospirosis is especially scary because the bacteria can infect humans.
It is important to observe
good rules of hygiene, such as hand washing after handling the pet
and even wearing latex or vinyl
gloves when cleaning up urine or other body fluids. Pets suspected
of having this illness should be
quarantined from contact with other pets or any household members incapable
of maintaining good
hygienic practices.
People who own pets that congregate in spots such as parks, dog shows,
sporting competitions and
other events should be careful about exposing their pets to places
where water may be contaminated
with urine or where there may be enough urine contamination to pose
a risk. This can be very difficult
to manage. It would be nice if there were an effective vaccine for
the current crop of leptospirosis
infections but there is not. If the older strains of this disease begin
to reappear as vaccinations are no
longer given it may be necessary to reconsider the risk/benefit ratio
of those vaccines as well.
It is very likely that one of the vaccine manufacturers is working on
a new leptospirosis vaccination but
I have no way of knowing whether that is the case. It would be worthwhile
to check with your vet
occasionally to see if there is a vaccination available if your pet
fits the "high risk" profile of a dog or
cat that is exposed to potentially contaminated water sources or is
frequently in contact with large
numbers of pets from all over the country.
All in all, leptospirosis is still pretty rare. It is still a good idea
to consider it whenever kidney disease
occurs in a young to middle aged pet or when uveitis (ocular inflammation)
occurs for no known
reason.
The new vaccines do protect against the two strains causing most of
the recently recognized cases of
leptospirosis.
Leptospirosis should also be considered when signs of liver disease
are present. Due to the
water-borne nature of this bacteria, it is especially important to
remember it as a cause of problems
after flooding or extraordinarily heavy rains.
Hope this clears things up a little.
Mike Richards, DVM
3/2/2000
Rabies transmission
Question: Been meaning to ask this question: I did read
your paper on Rabies &
remember the time frame for the bite transference, but is it possible
to
transfer the virus via salvia without a bite? I.E. two
animals hissing
at each other? and left behind in salvia on something such as
a dish or
rug or concrete? If so, how long does the virus live on these
items?
I live in a semi-wooded area full of darling, displaced raccoons, possum
and fox, and many others. (housing construction.....damn the developer
to
hell anyway for not giving one single bit of consideration to the animals!).
My boys are strictly house-bound, but I do like to let them out on the
porch for air and sun.
When you have time...........thanks so much!
Best Regards,
Lyn
Answer: Lyn-
It is possible to transmit rabies through saliva entering a pre-existing
wound. There are rare cases in which the virus is aerosolized and enters
wounds, as well. I know this has happened at least once in a
laboratory. However, the risk of rabies transference in either
of these
cases is pretty low, since it circumstances have to be just right.
Rabies
virus does not survive outside the body for more than few seconds,
in most
cases. If an animal dies of rabies, the rabies virus may survive for
up to
two days in the body, though. This is a good reason to keep pets
away from
dead raccoons, opossums, ground hogs, etc.
There has not been a case of rabies, with the currently available vaccines,
in a properly vaccinated pet. I am hoping that record is never broken.
I think your guys are safe from rabies. We have seen some nasty bite
wounds
from raccoons, though. So do continue to be cautious, as you have been.
Mike Richards, DVM
5/8/2000
Rabies Information in Virginia
-Possible infection from pet
Q: Hi ,I recently lost my 15mo. old Scottish Fold.
I rose to find he had been sick all night & vomited repeatedly through
out the house. He would try to drink & immediately bring it back up.
I rushed him to the vet. The vet could not find anything wrong but gave
medication for the vomiting & an antibotic. Vomiting stopped &
he seemed okay, eating & playing. Three days later, I rushed him to
the vet with a sudden, severe respiratory problem. Given short & long
reacting Cortisone shots & antibotics. I was much more worried than
the vet seemed to be because it just seemed so severe. He then hid in a
corner and wouldn't move for anything, nor would he take food or water.
I stayed by him all night trying to keep my eye on him. At 2am he rose
to go to the litter box. I followed. It took him forever & he layed
down to go, just the tiniest squirts. He was far too weak for just one
day without food & water! Leaving the box, he stumbled & fell.
Then I bend down to pet him & barely touched his back & his hind
legs slipped out from under him! His eyes were too big, dialated &
glossy looking. I rushed him immediately to the vet. A steady body tick
developed in his hind legs. Broad spectrum antibotics, anti- inflammatories
for throat swelling, etc. with no improvement. He quit all food & water
intake & was on IVs. Later, on one side of face & tail, twitching
& started "foaming at the mouth." Vet & 2 universities consulted
with, came up with toxoplasmosis or rabies. (Surprise, the previous vet
didn't vaccinate for rabies! I had previously quit that office because
too busy, confusion & disorganized! Cat raised indoors strickly! Only
allowed out in back yard after 1yr old & for short durations. Not exposed
to other animals!) Finally, the toxo.test result came back...negative!
We had to put him down. Then rabies, negative. His blood work was clear,
no evidence of disease in organs or tissue samples. State Health Dept.
distroyed brain tissue, in error, that was to go for further testing. The
vet now says he doesn't have a clue. If he had to say something, he would
say viral meningitis. He does seems to be quite sure it was a virus of
some sort. This cat's litter mate has started showing signs of illness
but quite different. This cat is choking & gaging during & after
eating. He is eating well though & somewhat active. He was started
on the broad spectrum antibiotics immediately.
Questions: Do you think viral meningitis? Zoonotic? Are most viruses
zoonotic? The health dept. said to me, "We keep a small frozen tissue sample,
for a year, incase someone dies, we can retest." Ahhh! How accurate is
this test?! As soon as the toxo. came back negative, I contacted the state
health dept., the rabies anti-serum is only available though them. They
denied saying it couldn't be rabies, besides if it was I would have months,
no rush. How wrong! They wouldn't even listen to how I was exposed! However,
to the vet they had a different story & told him he had to put down
this animal. Wouldn't it be against state & federal laws to deny the
anti-serum under these circumstances? I would be a class III exposure according
to the CDC. Who would you contact regarding this?
FYI, Two days after the negative diagnoses, the newspaper headlines
were: "Rabid Cat Infects Family" According to the article this area has
been under an rabies alert since april. I find myself worring about my
daily headaches that have started at this time. They could be tension or
stress, I don't know, I don't normally get them but this has been stressful.
Karen
A: Karen- I wish that I could help supply some
insight as far as a diagnosis goes but in reading your note I was thinking
in such a totally different direction that I think I must have misunderstood
part of it. My thoughts were of urinary blockage and pleuritis or other
respiratory illness. These almost certainly would have shown up on an autopsy,
though. Farther into the letter it did seem more like rabies or toxoplasmosis
would be good diagnostic rule-outs. Rabies would be the major zoonotic
concern. I can't think of another cat virus that has the potential to infect
humans.
There are several tests for rabies but the most commonly used one is
the fluorescent antibody test. I could not find specific data on the accuracy
of this test but I remember seeing something on this and there was a small
margin of error (I think it was about 2%). I can't say this is true everywhere
but our health department is pretty careful about any possible case of
rabies in which saliva could have contacted an open wound. If you think
this is possible I'd call your physician. Again, I can't say this is true
everywhere but I don't recall a case in which the health department was
not cooperative when a local physician felt that rabies exposure was possible
even when testing was negative. I do not recall the health department using
rabies serum, though. I only remember a couple of clients being vaccinated
with the three or five dose regimens.
The state lab and the local health departments often have differing
views on how to handle these cases so if you have only spoken with the
state level health department you might want to try your local one.
In Virginia our best reference for rabies information is Dr. Suzanne
Jenkins of the state health department. She is considered an expert on
rabies and may be a good source of information for your physician or veterinarian.
Dr. Deborah Brigss at Kansas State is also supposed to be a leading expert
on this disease if you live nearer to Kansas than Virginia.
It may be reassuring to know that of the rabies cases in humans in the
United States in the last few years 15 out of 17 cases involved exposure
from bats -- only two exposures resulting in rabies occurred from other
animal bites. The testing must be pretty accurate if all possible exposures
resulted in only two cases of rabies.
I have sweated out this situation personally. I know the anxiety it
can cause to be bitten by a potentially rabid animal. Keep working with
your vet and your physician to understand the situation fully and to develop
an appropriate plan of action.
Mike Richards, DVM
HIV
AIDS -can dogs and cats get infected
Q: I am looking to find some information with regard
any truth that cats and
dogs are getting HIV AIDS due to used syringes in parks and streets.
I
have not heard this and am trying to track information to veryify this
one
way or another.
thank you
Angela
A: Angela-
It is always hard to be absolutely certain that there is no truth at
all
behind a rumor like this. However, there are no reports that I am aware
of
in the veterinary or the human literature suggesting that either dogs
or
cats can be infected by the human immunodeficiency virus. Therefore,
it
seems to be almost impossible that this could be happening.
There is some confusion regarding the difference between human
immunodeficiency virus (HIV) and feline immunodeficiency virus (FIV).
These
are entirely different viruses and there has been no indication in
the
literature that these strains of virus can cross react. The FIV virus
has
been used as a model for studying the human infection and this research
has
been published. One example was the recent "Lessons from the cat: feline
immunodeficiency virus as a tool to develop intervention strategies
against
human immunodeficiency virus type 1", by Elder et. al, AIDS Res
Hum
Retroviruses, June 1998. It can be hard for people to accept that such
closely related viruses do not cross species lines but that appears
to be
the case based on studies to date.
If dogs have a retroviral infection similar to HIV it has not been
identified. There is some suspicion that they do and a recent paper
"Possible relationships between canine hematopoietic neoplasia, other
malignancies and immune mediated diseases" by G. Theilen, in Leukemia
April
1997 suggested that there may be an unidentified retrovirus infecting
some
dogs. However, it has not been suggested that this is human
immunodeficiency virus.
Dogs and cats are both being used in studies relating to the control
or
cure of HIV but these studies do not involve infection of dogs or cats
with
the HIV virus. They relate to things like immunosuppression of T cells
with
cyclosporin or similar treatments that are studied in dogs or cats
in the
hope that the information will apply to human patients who actually
are
infected with HIV.
You can search for information on HIV at the PubMed site:
http://www.ncbi.nlm.gov
I hope this helps to set your mind at ease.
Mike Richards, DVM
2/16/99
Distemper possible
Q: I am still at loss what really killed
my 9 yrs old dog. I had brought a
puppy home from the pound unknowing it had distemper, I found this
out on a
routine checkup and the 6week pup went into seizures, The vet put her
down. Now my
other dog who was exposed to this pup <whom I just received from
my mom >
unknown which shots she received became sick too,, I took her to the
vet,,
she was throwing up yellow mucus,, not eating and panting real
hard and had
discharge from her eyes,, I was convince it was distemper.. my vet
after
series of test,, x-rays bloodworks,, told me he did not think
she had
distemper but had heartworms but was not to bad to save,,
To my surprise.
he put her on some antibiotics for her eyes worming meds
for whipworm and
hook worm and another anti cephalexin. told me she had some heart
damage
and lung disease but should be okay,, So I took her home on thurs
and brought
her back in sat morn cos she was not eating or drinking and panting
harder,, he
did some more test said c cells was OK but he thought she
may now have a
bateria infection,, he put her on an IV cos she was so dehydrated,,
I
said I think she should be put down,, he said no thought
we could try and if she
was not eating or drinking anything by Mon morn.. we would has
to cross that
told us to try to get her to eat anything.. I was skeptical.. 5 hrs
later
she died in my arms.. she was panting so hard I thought she was
going to
explode. he still can't tell me what killed her.. I don't know what
to think,, Either
he was going way out to save her or to add to his
pocket book,, I think
what I am looking for did she die from heart failure or
distemper.
I have another puppy at home who I am scared to death may loose
too cos he is too
young to have all shots,, Is there anything else can kill a dog like
this
besides distemper or not? My puppy has a runny nose but I was
told it
has an upper resp cold and is on antibiotics I am wondering am I in
for an another
cleaning or not??
A: S-
I think that I would be suspicious of distemper with the clinical signs
that you note, but it is not possible to be certain unless an autopsy
was
done. Distemper is very hard to diagnose with certainty in many cases
and
it is not that unusual for a dog to die from it before a definite diagnosis
can be made. Heartworms can produce severe illness rather suddenly
in some
cases (when the heartworms cross over into the venous circulation from
the
liver) and this could have been the problem, as well. There are
unfortunately a lot of possibilities.
I wish that I could help more. I hope that the puppy is doing better
by
now. Sometimes even if distemper is the problem the maternal antibodies
will protect a puppy long enough for the distemper virus to be cleared
from
the environment. Clean what you can with chlorine bleach diluted
about
1:30 to lessen the risk of exposure. Vaccinate the puppy according
to your
vet's advice. I know that you have had a rough time but perhaps luck
will
go your way, this time.
Mike Richards, DVM
Possible distemper -
possible zoonotic
Q:dear dr. mike, my family recently rescued a dog
from a local animal shelter. About 6-8 days after having the dog , he started
with a dry cough ( a choking sound). he was seemingly in good spirits,
besides a lot of sleeping , he was fine. a day or two later, i noticed
a greenish discharge from his nose. I plan on a trip to the vet, but i
was hoping for a quick reply from you to end this wondering & worrying.
i appreciate your time. thanks. M-
A: Sometimes I got too much email for quick replies.
I hope that you did take your dog to your vet. The symptoms you are seeing
could be signs of distemper virus infection, which is serious. I hope it
is something less dramatic, like tracheobronchitis, though.
You definitely need your vet's help, though.
Mike Richards, DVM
Giardia
Giardia is a protozoan parasite that lives in the intestine of affected
animals. It is unclear whether there are several species of this parasite
or whether there is one species that affect several different animals,
including people. These small parasites are very easy to miss on a fecal
exam and may not be present in the stool of animals infected with the organism.
Repeated fecal exams are sometimes necessary to identify this parasite.
Not all animals in which infection can be demonstrated have clinical signs.
This leads some people to believe that the parasite may not cause disease
. Most vets think that there may just be other factors, like the animal's
immune response to the parasite that cause some animals to develop disease
and not others. Clinical signs of giardia include weight loss, inability
to gain weight appropriately during growth, diarrhea, vomiting, lack of
appetite and greasy appearing stools. Them most commonly used medication
for giardia infection is metronidazole (Flagyl). The organisms come from
the environment and live in moist to wet areas. They are susceptible to
quatenary ammonium disinfectants, Lysol and dilute chlorine bleach. Keeping
the dog's environment dry helps a lot.
This disease may be contagious to people from infected dogs so good
sanitary practices, like washing your hands after handling an infected
puppy, are very important. If a family member develops similar clinical
signs, a physician should be consulted.
Mike Richards, DVM