April Edition 2012
New Clients
We wanted to take the time to welcome the following new patients to our
practice:
Ares Hoxhallari
Chance Gooch
Checkers Harding
Savannah Filson
Sally Ristine
Boaz Thielmann
Pepper Mohr
Butters Anderson
Murphy Reagan
Maxey Rivers
Francine Ward
Layla DeHaven
Mika Rollo
Kobe Lohrke
Charlotte & Kirby Evans
Tyson& Sophie Kaltz
Rocky Norris
Blue Bell
Goldie Ray
Terry Allen
Oliver Tilden
Chowdah Perry
Riley Greene
VW Bethune
Sophie Burchell
Coal Hopkins
Gigi Sherman
Bella Ward
Rottie Kerr-Geiger
Puss Montgomery
Pussy Cat (Scottie) Sullivan
What are heartworms?
Heartworms are a blood parasite of dogs and cats. They are transmitted to the
animal through a bite wound from some types of mosquitoes—they do not cause
disease in people. In our area of Florida, we have several factors that make
heartworms a risk to our pets. First of all, we have a warm, humid climate and
plenty of water that helps the mosquito population to flourish. We also have the
types of mosquitoes that carry heartworms, and susceptible hosts (our dogs and
cats!)
When a mosquito carrying heartworm disease takes a bite, the
first thing that happens is the mosquito spits on the skin as it bites
in. The spit contains the heartworm larvae. The larvae get into the
animal through the bite and sit in the skin and underlying tissue.
After approximately three months, the larvae start moving through
the blood towards the heart. They stop in the vessels that
connect the heart and the lungs and mature into adult worms. Once they
become adults, they reproduce and shed more larvae into the blood stream to be
picked up by mosquitoes taking a drink, and then are carried to another animal.
Are dogs and cats affected the same way?
No. The dog is the “normal” host for the heartworm and the cat is
not. When the dog becomes infected with heartworms, the lifecycle
usually completes and full adult worms are made. These adult
worms can be numerous (sometimes greater than 20) and are
usually very long (up to 14 inches). Adult worms can damage the
dog’s blood vessels, block the lung passageways, and can clog up
the heart leading to heart failure and death.
It is important to understand that because mosquitoes do get inside,
even indoor only cats are at risk of heartworm infection. Results from a
University of Florida study showed that almost 5% of the unprotected cats had
adult heartworms and 17% had evidence of infection in their blood. When a cat
becomes infected, its immune system immediately goes to work trying to kill the
larvae and most of the time it is successful. It is not as common for heartworms
to make it to the adult stage in cats. That being said, the dead larvae cause a
significant danger—irritating the vessels and lungs causing coughing and
respiratory distress. This inflammatory lung disease is called “Heartworm
Associated Respiratory Disease (HARD)” in cats. HARD can be fatal if the lungs
become damaged to the point at which the cat cannot breathe. If a cat does
develop an adult worm, it is at risk for sudden death.
How do you diagnose heartworms?
In dogs, adult heartworms can often be detected by an “antigen”
blood test. Antigen is a material from the parasite that can be
picked up on tests. When you bring your dog in for a heartworm
test, this is the test that is performed. Heartworms in the larval
stage can be found by looking at the blood under a microscope. It is
important for dogs to be tested for heartworms before starting
heartworm prevention so infection can be found and treated safely.
In cats heartworm diagnosis is much more difficult. This is mostly due to the fact
that cats rarely have adult worms, so there is often little to no “antigen” in the
cat’s blood. Sometimes an “antibody” test can be performed that looks for
exposure to heartworms, but the antibody levels in the cat’s blood often rise and
fall and can be very unreliable. The best test for finding heartworms in the cat are
seeing signs of the disease (coughing) along with some tell-tale changes in the
lungs that can be seen on an x-ray.
How do you treat heartworms?
At Plantation Animal Hospital, we take heartworm disease very seriously. When
we determine that a dog is positive for heartworms, we recommend a work up to
figure out what stage/class of disease is present. Once we classify the disease,
we will create a treatment plan. For most dogs, we will recommend a series of
injections to kill the adult worms (“adulticide” treatment). It can be tricky to kill the
adult worms, because if they are killed too quickly they can cause severe shock.
Typically, we recommend a course of antibiotics followed by a series of injections
to kill adult heartworms. The injections can be costly, and dogs being treated
require close monitoring both in the hospital and at home. The success rate of
killing the heartworms with injections is very good, the dogs that do well during
treatment and stay on heartworm prevention afterwards have a great chance of
being heartworm free in the course of a few months.
You may hear about an alternative treatment for heartworms in dogs called the
“slow kill” method which is commonly used by shelters and rescue groups
because it is less expensive than “adulticide” treatment. This treatment consists
of giving heartworm prevention at more frequent intervals. The prevention
sterilizes the adult worms so they cannot reproduce but it does not kill them.
There are certainly cases in which this method may be preferred, but the risk of
using this plan is that it can take as longs as two years for the adults to die—and
they can certainly create a lot of damage to the dog’s body in that time.
In cats the treatment is much different. As stated, it’s rare for cats to develop
adult heartworms, and even if they do the drugs used to kill adult heartworms in
the dog are not safe to use in the cat. When treating heartworms in cats our
primary goals are to get the cat on heartworm prevention and to ease the
symptoms of the disease while the cat’s immune system goes to work. Antibiotics
and steroids are the primary drugs used to help the cat while it clears heartworm
infection. It is possible for heartworms to cause severe damage to the cat’s
lungs. As a result, some cats require long term treatment with medication.
What heartworm prevention is best?
There are lots of choices for heartworm prevention on the market. At Plantation
Animal Hospital, we have chosen to carry the products we trust the most and our
entire staff is trained to discuss them with you in detail. When picking out a
heartworm prevention, it is important to remember that the companies that make
these products only guarantee their success if they are purchased from a
veterinary clinic. Online pharmacies and pet supply stores that sell these
products do not come with this guarantee. Of the products we carry, we don’t
mind which heartworm prevention you choose—as long as your pet gets it every
month!!
Note: Arpil 10th is National Pet day!
Plantation Animal Hospital
7165 Highway 17
Fleming Island, FL 32003
www.plantationanimalhospital.net
904-284-0087