|
Successful flea control has two
aspects. Fleas must be controlled on your pets, and fleas
must be controlled in your pets’ environment. Since cats
and dogs share the same fleas, the presence of both species in
your pets’ environment can make flea control much more
difficult. All pets in a household must be effectively
treated, even if it appears that only one pet is being bothered
by fleas.
Diagnosis
of Flea Infestation
When a dog or
cat is heavily infested with fleas, it is easy to find the
fleas. If the numbers are small, it is best to quickly
turn your pet over and look on its belly. If you do not
find fleas there, look on the back just in front of the tail.
Be sure to part the hair and look at the level of the skin.
Also look for "flea dirt." Flea dirt is digested blood
left behind by the fleas. Flea dirt is actually fecal
matter from the flea. Finding flea dirt is a sure
indication that fleas are present or have been present recently.
Flea dirt
looks like pepper. It varies from tiny black dots to
tubular structures about 1/32" (1-2 mm) long. If you are
not sure it is flea dirt, put the suspected material on a light
colored tabletop or counter top. Add one or two drops of
water and wait about 30 seconds. If it is flea dirt, the
water will turn reddish brown as the blood residue goes into the
solution. Another trick is to put some of the material on
a white paper towel and then wet the paper towel with water.
A red stain will become apparent if you gently wipe the material
across the surface of the paper towel.
Many people
find tiny drops of blood in a pet's bedding or where the pet
sleeps. This is usually flea dirt that was moistened, then
dried. It leaves a reddish stain on the bedding material
and is another sign that fleas are present.
Life Cycle
of the Flea
To appreciate
the complex issue of flea control, you must understand something
about the flea's life cycle.
Although you
are only able to see the adult flea, there are actually 4 stages
of the life cycle. The adult flea constitutes only about
5% of the entire flea population if you take into account all
four stages of the life cycle. Flea eggs are pearly white
and about 1/32" (1-2 mm) in length. They are almost too
small to see without magnification. Fleas lay their eggs on the
pet, but the eggs do not stick to your dog or cat's hair.
Instead, they fall off into the pet's environment. The
eggs make up 50% of the flea population. They hatch into
larvae in 1 to 10 days, depending on the temperature and
humidity in the environment. High humidity and high
temperature favor rapid hatching.
Flea larvae
are slender and about 1/8-1/4" (2 - 5 mm) in length. They
feed on organic debris found in their environment and on adult
flea feces, which is essential for successful development.
They avoid direct sunlight and actively move deep into carpet
fibers or under organic debris (grass, branches, leaves, or
soil). They live for 5 to 11 days before becoming pupae.
Moisture is
essential for their survival; flea larvae are killed by drying.
Therefore, it is unlikely for them to survive outdoors in areas
of strong, direct sunlight. Outdoor larval development
occurs only where the ground is shaded and moist and where
flea-infested pets spend a significant amount of time.
This allows flea feces to be deposited in the environment. In
an indoor environment, larvae survive best in the protected
environment of carpet, along baseboards, under and inside
upholstered furniture, or in cracks between hardwood floors.
They also thrive in humid climates.
Following
complete development, the mature larvae produce a silk-like
cocoon in which the next step of development, the pupa, resides.
The cocoon is sticky, so it quickly becomes coated with debris
from the environment. This serves to camouflage it.
In warm, humid conditions, pupae become adult fleas in 5-10
days. However, the adults do not emerge from the cocoon
unless stimulated by vibrations, carbon dioxide, and heat.
Pre-emerged
adult fleas can survive up to 140 days within the cocoon.
During this time, they are resistant to insecticides applied to
their environment. Because of this, adult fleas may
continue to emerge into the environment for several weeks
following insecticide application.
When the adult
flea emerges from its cocoon, it immediately seeks a host
because it must have a blood meal within a few hours to survive.
It is attracted to people and pets by body heat, movement, and
exhaled carbon dioxide. Following the first blood meal,
female fleas begin egg production within 36 to 48 hours. One
female flea typically produces 40 to 50 eggs per day. Egg
production can continue for as long as 100 days, which means
that a single flea can produce thousands of eggs in her short
lifetime!
This entire
life cycle (adult flea >>> egg >>> larvae >>> pupa >>> adult)
can be completed in 14-21 days with the proper temperature and
humidity conditions, but it may also take much longer if
environmental conditions are not ideal. This adds to the
problem of flea control.
If untreated,
the female flea will continue to take blood for several weeks.
During that time, she will consume about 15 times her body
weight in blood. Although the male fleas do not take as
much blood, they, too, contribute to significant blood loss.
This can cause a pet to have an insufficient number of red blood
cells, which is known as anemia. In young or debilitated
dogs and cats, this anemia may become severe enough to cause
death.
Flea
Control
Successful
flea control must rid your pets of fleas and it must rid your
pets’ environment of fleas. In fact, environmental control
is as important as treatment of your pet. If your dog or
cat remains primarily indoors and you do not have other pets
that come in from the outside, environmental control is
relatively easy, especially with the advent of the newer topical
and oral products (see below). However, the dog or cat
that goes outdoors frequently, or stays outdoors, presents a
greater challenge and a few fleas may occasionally be seen
indoors.
Many of the
older insecticides (which have been the mainstay of flea control
for years) have limited effectiveness against fleas because they
are only effective for a few hours after application on the pet.
Also, these are primarily geared to kill adult fleas. Flea
powders, sprays, and shampoos will kill the fleas present on
your pet at the time of application. However, most of
these products have little or no residual effect, so fleas that
return to your pet from his environment after the pet is treated
are not eliminated by these products. Thus, your dog or
cat may be covered with fleas within a day after having a flea
bath or being sprayed or powdered.
However, there
are some newer, more effective sprays that can be a valuable
part of the overall treatment plan. They kill adult fleas
rapidly and are safe enough to use daily, if necessary.
Flea sprays containing insect growth regulators are helpful in
managing the overall problem because they help to break the flea
life cycle by decreasing the number of flea eggs that hatch.
In general, flea sprays, collars, powders and dips have become
less popular since the introduction of the newer, safer and more
effective products.
Newer
Products
There are
several newer topical treatments that are applied to the back of
the pet’s neck. Frontline PlusTM
and AdvantageTM
are two very effective products; because they remain topical
and are not absorbed through the skin they are also extremely
safe. Both kill adult fleas for a full month.
Frontline Plus also kills ticks and contains a second ingredient
that helps kill flea eggs as the female flea deposits them on
your pet’s skin. There are many other products that are
designed to be used once a month and are applied in a similar
manner to these two. All have specific advantages and
disadvantages. Ask your veterinarian about any of these
products prior to using them. Be careful! Some of
these other products cause severe illness or fatalities if used
on cats or debilitated dogs. Never use any flea product
that is labeled “for dogs only” on a cat; fatal reactions can
occur!
A new product,
known as ComfortisTM, is a meat-flavored “flea pill”
that is administered once a month. It is currently
approved for use in dogs only, but research is ongoing regarding
a possible future formulation for cats. ComfortisTM
has one big advantage over the topical monthly medications – it
kills the adult fleas on your pet much faster, thereby reducing
the number of flea eggs shed into your pet’s environment.
Another
meat-flavored, monthly “flea pill” is called ProgramTM.
This medication does not kill adult fleas but it does kill flea
eggs and larvae. When the female flea produces eggs, the
eggs do not hatch. In effect, this product acts like a
birth control product for the flea. Giving this product
has the effect of treating your house for fleas without spraying
anything in your house. This very safe product is
available for both dogs and cats. The monthly pill for
dogs is available alone (ProgramTM
tablets) or combined with a heartworm preventative (SentinelTM
tablets). Cats may also take a monthly ProgramTM
tablet or monthly ProgramTM
liquid oral preparation. In addition, there is an injection
available for cats to be administered by your veterinarian which
will provide the ProgramTM
flea egg control for 6 months after a single injection.
Because of its effectiveness in controlling the flea egg
population, the consistent use of ProgramTM
(or SentinelTM) is an excellent way to help prevent a
flea infestation from occurring in your home in the first place.
If you have
any pet species other than dogs or cats in your household, check
with a veterinarian familiar with the species to determine which
product(s) will be most safe and effective for them.
Environmental Control
The newer
topical and oral products do not require the aggressive
environmental control that is necessary if only dips, sprays, or
collars are used. This is one reason why they have become
so popular with pet owners. Many people try the newest
products for 1-2 weeks to see if they provide adequate flea
control alone. Please consult with us about the
requirements for your specific situation.
When
environmental flea control is indicated, it must be directed at
both your house and your yard. Remember: adult fleas live
on animals; flea eggs, larvae and cocoons are everywhere else.
Therefore, when treating the environment, concentrate on
killing those eggs and larvae! Remember also, no chemical
will kill the cocooned stage of the flea. The only way to
eliminate the cocooned stage is to wait for the adult flea to
emerge, and then kill the resulting adult flea. Your
veterinarian will be able to help you choose the most effective
products for your situation.
House.
Even though large numbers of flea eggs, larvae and cocoons may
be in your house, most people never see them. A
professional exterminator may be called to treat your house or
you may use a house fogger or a long-lasting spray. You
should purchase a fogger or a spray that kills the adult fleas
and inhibits development of the eggs and larvae. In
climates with extended warm temperatures and high humidity, it
may be necessary to treat two or three times with a 30-day
residual product before all stages of the fleas are removed from
the house. The second treatment is most effective if it is
done 2 weeks after the first.
As a rule,
flea eggs and larvae tend to concentrate at the edges of rooms,
along the baseboards, under furniture, inside upholstered
furniture and deep inside carpets. Thus, sprays applied
directly to these areas are generally more effective than
foggers. Fogger mists tend to fall out of the air in the
center of the room, and access areas under and inside furniture
very poorly. Fogger sprays also do not turn corners well,
so an individual fogger is generally necessary for each room in
the house. Therefore most homes require less product to be
used if sprays are utilized instead of foggers.
Yard.
Yard control may also be done by professional exterminator or
with various products you may use yourself. Be sure that
any insecticide that you use has a 30-day residual. This
keeps you from having to spray every week. In climates
with extended warm temperatures and high humidity, it will often
be necessary to treat monthly during the warm months of the
year. You should use a 30-day residual product each time.
Concentrate your spraying to the cool, moist areas of your yard,
especially the areas where your pets like to stop and rest.
Re-emergence of Fleas
If you recall,
a pre-emerged adult flea can survive up to 140 days within the
cocoon. This is significant when your pets are gone from
home for extended periods of time. During the time that
the house is quiet and empty, the fleas present in your home
continue their development from egg to larvae to cocoon.
But without their mammalian hosts’ activity in the house, the
pre-emerged adults remain in their cocoons. Even if the
house was treated with an insecticide, their cocoon protects
them. When people and pets return to the house, the adult
fleas emerge from their cocoons en mass and immediately begin to
seek a blood meal. They jump on cats, dogs, and even
people. Although it may appear that a dog just returned
from boarding brought fleas to your home, it is also very
possible that a sudden emergence of adult fleas may account for
the fleas present. If large numbers of fleas are seen,
they are almost certainly newly hatched fleas and have not come
home with your pet.
Additional information regarding pet
health may be found in our Medical
Watch section. |