THE MIGHTY MOSQUITO
(and heartworms)
by Faith Hughes, DVM
Not everyone knows how dangerous the tiny mosquito
can be for a dog or cat. This teeny
beast is responsible for transmitting the microscopic babies of Dirofilaria immitus)that can grow into 6 to 12 inch worms
in your pet. It's obvious that
heartworm disease is common in the Southeast U.S.
because of the the, because a
mosquito can be swept a mile on the wind and mosquitoes can sneak into your
home. Dogs are the most susceptible,
but we do see cases of heartworms in cats.
(heartworms mosquitoes that we battle year
round. Your pet doesn't have to come into contact with another cat or dog.
Most dogs who have adult
male and female heartworms also have microscopic heartworm babies called
microfilaria (or stage 1 larvae) that circulate in the pet's blood
stream. A mosquito bites the pet and
ingests the microfilaria along with it's blood
meal. Inside the mosquito, the stage
1 larvae molt into stage 2 larvae.
The mosquito then bites a cat or dog and injects the larvae into
that pet's skin. This larvae stays in the skin 30 days (hence the use of
once monthly heartworm prevention) prior to beginning it's 5 month journey migrating
through the body on it's way to the pulmonary artery in the lungs. The adult worm in a dog can be 12 inches
long and will cause damage to the arteries, lung tissue, and heart.
Early in the disease, your pet may show no signs. Once the disease progresses you can see
coughing, wheezing, exercise intolerance, vomiting in cats, fluid buildup
in the abdomen, or sudden death.
Diagnosis of heartworms in dogs is made by a
simple blood test that takes only 10 minutes to run. The test will detect
antigens which are like a chemical and are secreted by the adult worms. The
worms must be at least 5-6 months old before they will be detected by
testing. Yearly testing of dogs is recommended because it's better to catch
heartworm disease early rather than waiting to see if signs develop. Even if your pet is on prevention, you
may have forgotten to give a tab or the pet may have spit out a tab without
your knowledge. Testing in cats can be tricky because they may only have
one worm that doesn't secrete much antigen.
The good news is that PREVENTION is safe,
effective, and affordable. For as little as $4.00 per month, you can't
afford NOT to prevent this disease.
Remember, prevention and treatment are two
different things. Preventions such as Iverheart, Heartgard Plus, Interceptor, Sentinel, and Revolution
are designed to keep your pet from getting the worms in the first
place. Treatment with Immiticide is designed to kill adult worms that your
pet already has. Puppies that are started on prevention at 6 weeks and take
it once monthly for life will never get heartworms. Since a heartworm has to be at least 5
months old to show up on a test, puppies less than 5 months old do not need
a test prior to starting prevention, but should get tested 6 months after
beginning the meds. Dogs 6 months
and older (who have never been on prevention) need a test first. If the test is negative, start prevention
and retest 6 months later then regular yearly rechecks.
Cats can be tricky
because it make take 2 different tests to know their true heartworm
status. The problem with cats is that you cannot treat them for
heartworms if they already have them. The medication
(Immiticide)that is used to kill the adult worms in dogs is not
tolerated well by cats and is dangerous to give. Cat's don't tolerate
the death of an adult heartworm in their lungs very well. This is
why one of the most common symptoms of heartworms in a cat is sudden
death. If a cat has heartworms, we will put them on a safe prevention
to keep them from getting anymore worms.
So, we've talked about the mosquito, life cycle of
heartworms, symptoms, testing, prevention. Now we need to talk about what to do if a
dog has adult heartworms. There are
a lot of variables that a veterinarian must consider when trying to give a
pet owner a prognosis for their pet...size of pet, how many worms, does pet
have symptoms, results of chest Xrays and bloodwork done on kidneys and liver. And no one can
ever tell you that your pet will be OK.
You have to remember that this worm is big and can cause lots of damage.
Treatment with Immiticide can run into the
hundreds of dollars.
When the 12 inch worms die, they will be swept
into the lungs like a thrombus or blood clot and can cause damage to the
lungs. If the dog is a big dog and only has a few worms then he has a good
prognosis. If it's a tiny dog with tiny lungs, then the pet has a worse
prognosis because they can't handle the damage to the lungs as well as a
big dog with big lungs. If the heartworm test shows a lot of worms, or if the pet is already showing symptoms of
disease, then prognosis is worse.
The bottom line is that no one can promise you that the dog will be
fine.
Many vets will put heartworm positive dogs on a
particular once monthly prevention as soon as they are diagnosed with the
worms. There are several reasons for this.
Prevention will keep the dog from getting more adult worms. The owner of the pet may decide they
don't want to have the pet treated with immiticide
because of the risks or the costs.
You have to remember that the prevention will not kill the worms
that the pet already has, but maybe the pet can live longer because it
won't get more worms and maybe the pet will live longer than the worms. An
average heartworm in a dog lives around 4 years. A heartworm that gets a dose of once
monthly prevention may only live 2 years. If you don't treat with Immiticide to kill the adult worms, it's kind of like a
game of Russian Roulette. Who will
live longer, the pet or the worm?
So my biggest
recommendation? PREVENTION,PREVENTION,PREVENTION. It's always
better to prevent than to treat. Preventative medicine is the way
to go, it's cheaper and healthier for your pet. And don't forget
to give heartworm prevention every month, don't skip winter months, for
the lifetime of your pet. For more info, log onto
www.veterinarypartner.com.
Return to Educational Articles
|
Wish
List
$$$$
Dr. Bronner's Peppermint Shampoo
Towels (no holes please)
Rugs
Blankets (no holes please)
Pet Store Gift Cards
Crates
Kongs all sizes
Wal-Mart Gift Cards
Clay Litter
Stainless Food Bowls
Nylabones
Paper Towels
Office Supplies
Small Animal Crates
Cat & Dog Toys
Laundry Detergent
Dishwashing Soap
Shelter hours:
Monday—closed
Tuesday-Wednesday—
11am-4:30pm
Thursday—11am-7pm
Friday—11am-4:30pm
Saturday—10am-4:30pm
Sunday—1-4pm
Map
Use GoodSearch
for your internet searches and help raise money for CHAT
|
