Veterinary Public Health Program
313 N Figueroa St. Rm 1127
Los Angeles, CA 90012
Tel (213) 989-7060
Tel: (877) 747-2243
Fax (213) 481-2375 vet@ph.lacounty.gov
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How do you know if your pet is
infected with heartworms?
The only way to know is by having
a blood test for heartworms performed at a
veterinary hospital.
What is the
treatment?
Veterinarians treat infected pets by
giving medication to kill the worms in the
bloodstream. As the worms die, there is a risk of the pet
having a bad reaction to the dead worms.
Therefore, heartworm disease is treated only
under the close supervision of a veterinarian.
Can humans catch heartworm?
Humans can potentially get infected if they are
bitten by a mosquito that is carrying the worm.
However human infections with Dirofilaria
immitis are very rare. In most cases, the
person had no symptoms, but small shadows ("coin
lesions") were seen inside the lungs on a chest
X-ray. No cases of human heartworm infection
have been reported in our county.
See articles in
blue box below for more information.
Local cases of heartworm
Since the beginning of 2005 until now (May 10,
2011), veterinarians in Los Angeles County have
reported eighty cases. Seven cases were in cats
and 73 in dogs.
In 28 of these cases, the pet
caught the infection in Southern California
(local cases). In 33 cases the pet was infected
outside of Southern California (imported cases).
In 19 cases there was not enough information
about the animal to say where they caught it
(unknown cases). The graph at the right
show these cases by year.
The majority of the cases
(70%) had no symptoms at the time it was
diagnosed. In the other cases, symptoms
included cough (21%), tiredness (13%), and heart
failure (6%).
In the past 5 years, several
cases of heartworm disease have been detected in
the area northeast of Downtown Los Angeles (see
cluster of back stars near center of map).
There are more heartworm cases
in the county that are not reported.
The Companion Animal Parasite Council reports
that over 130 pets tested positive for heartworm
in LA County in 2010. See their
interactive
map for details.
Untreated animals
In 10 of these 80 cases, treatment was not done.
Untreated animals may be "reservoirs" for the
disease. This means they can infect mosquitoes,
and then the mosquitoes can infect more pets.
Infected coyotes can be reservoirs for the
disease.
How Can I Prevent Heartworm
in My Pet?
1. Mosquito Control.
Mosquitoes breed in stagnant water. Stop
mosquito breeding by dumping any standing water
on your property every 2 days. Mosquitoes feed
the most at dawn, dusk and at night, so keep
your pet indoors at night.
2. Heartworm Preventative Medication.
Heartworm preventative medications are generally
regarded as safe and help prevent infection with
additional parasites. Discuss the issue with your pet’s
veterinarian.
