Entomology & Nematology Department
Prepared by Phil Koehler and Don Short*
External parasites are generally found on or in
the skin surface and are important pests because
they bite or annoy both humans and their pets.
Fleas, mange mites and ticks are the most fre-
quently encountered and most troublesome pests
which attack humans and their pets.
Fleas are small (1/16"), dark, reddish-brown,
wingless, blood-sucking insects. Their bodies are
laterally compressed, i.e. flattened side to side,
permitting easy movement through the hairs on
the host's body. Their legs are long and well
adapted for jumping. The body is hard, polished,
and covered with many hairs and short spines
directed backward. The mouthparts of an adult
flea are adapted for sucking blood from a host.
Several species of fleas may be pests in Florida,
and five kinds have been found on a single animal.
The cat flea is the most frequently found flea, al-
though the dog flea, human flea, and sticktight
flea are also found in Florida. These fleas may at-
tack a wide variety of warm-blooded animals in-
cluding dogs, cats, humans, chickens, rabbits,
squirrels, rats and mice.
The female flea lays her tiny, white eggs loosely
on the hairs, in the feathers, or in the habitat of
the host. The eggs readily fall off the host onto
the ground, floors, bedding or furniture. Some
fleas can lay 500 eggs over a period of several
months by laying batches of 3 to 18 eggs at a
time. The tiny eggs hatch in 1 to 12 days after
being deposited. The white, worm-like larvae
avoid light. They feed on particles of dead animal
or vegetable matter generally present in cracks
Florida Cooperative Extension Service
Institute of Food and Agricultural Sciences
University of Florida, Gainesville
John T. Woeste, Dean for Extension
and crevices. Within 7 to 14 days, unless food has
been scarce, the third larval stage is completed,
and the larva spins a tiny cocoon and pupates.
Usually after a week the adult fleas emerge and
begin their search for blood.
Fleas are known to remain in the pupal stage
from five days to five weeks in the absence of
hosts. Adults emerge from the pupal case when
vibrations from pets or humans let them know a
host is near. This is one reason why people re-
turning to an unoccupied home may suddenly be
attacked by an army of fleas.
Adult fleas must feed on blood in order to re-
produce; however, adults can live for long periods
without feeding. Fleas usually live and breed most
heavily where pets rest. Persons coming near
these resting places are also subject to attack. If
fleas are established in a home, they will feed on
man as well as on the pets. The usual places of
attack are the ankles and lower portions of the
The so-called "sand-flea" is nothing more than a
common flea that is breeding outdoors in the soil.
Contrary to belief, fleas cannot go through several
generations without having a blood meal.
The entire life cycle of a flea requires from
two weeks to two years. Hot wet summer months
favor egg laying. Hot dry periods give maximum
adult production so August to September usually
gives the greatest adult flea populations.
Fleas often breed in large numbers where pets
and other animals live. Pets infested with fleas
bite and scratch themselves constantly. Their
coats become roughened and the skin can become
infected. Symptoms of sensitized hosts are often
* Phil Koehler and Don Short are Assistant Professor and Extension Entomologist and Associate Professor and Extension Entomologist, respec-
tively, Department of Entomology and Nematology, University of Florida, Gainesville.
mistaken for mange. Cat fleas and dog fleas may
be intermediate hosts for the dog tapeworm.
Fleas attack people for a blood meal. Some peo-
ple suffer more from flea bites than other people.
Fleas are annoying since their bites cause intense
itching often resulting in secondary infection. The
usual flea bite has a small red spot where the flea
has inserted its mouthparts. Around the spot
there is a red halo with very little swelling. Many
people do not react to flea bites at all while others
are sensitive and suffer severe allergic reactions
to bites. Fleas may also vector such human di-
seases as plague, typhus and tularemia.
Flea control is difficult for pet owners to imple-
ment since two things must be done: 1) treat the
pet and (2) treat the premises. Pet treatment
alone is not sufficient because the animal quickly
becomes reinfested from untreated premises.
The following materials are recommended for
flea control on animals. Read and follow all label
directions carefully before applying insecticides to
2-5% carbaryl (Sevin)
0.5% coumaphos (Co-Ral)
5% malathion dust
.25% malathion dip
.5% malathion sponge
dichlorvos flea collars
Do not use Sevin dust on
cats under 4 weeks old.
Do not use coumaphos on
dogs under 2 months old.
Do not use on cats. Do not
use in combination with
other insecticides or drugs.
Sold under several trade
names. Flea collars are
sometimes effective on small
short-haired dogs that are
not subjected to flea-
infested areas. Other
treatments are usually
needed to supplement flea
control on large or long-
haired pets that are
allowed freedom out-of-
doors. Some pets may be
allergic to resin collars.
To be certain pets remain free of fleas, it is
necessary to make routine use of flea powders at
roughly 10 day intervals, especially if pets are al-
lowed to contact animals or premises that are in-
fested. Most commercial flea preparations will
control fleas if they are used properly.
Treatments should be applied carefully and rub-
bed into the fur working from the head to the
tail. Special attention should be given to the top of
the head, the neck and the back. Apply treat-
ments out-of-doors so fleas which leave the ani-
mals do not remain indoors.
Pyrethrin sprays or dusts are also available for
animal treatment. Pyrethrins will often paralyze
a flea rather than kill it. Pyrethrin treatments
should be made outdoors or over paper where the
fleas can be collected and destroyed.
Pets become reinfested with fleas from un-
treated premises. For most effective control,
sleeping areas, bedding, kennels and other areas
frequented by the animal should be treated at the
time the pet treatment is made. Treatments may
or may not include the use of pesticides.
Non-pesticidal premise control includes thor-
oughly and often cleaning the house. All rugs
should be thoroughly cleaned with a vacuum
cleaner or steam cleaner. Infested furniture, pet
baskets and cracks should be thoroughly cleaned
to prevent the larvae from finding food. Dirt
which is collected should be disposed of immedi-
ately to destroy fleas and flea larvae.
Many people remove pets from the home to at-
tempt flea control. Flea infestations usually be-
come more evident when pets are removed. The
hungry adults prefer to feed on cats and dogs.
When the pet is removed, the fleas overrun the
home frequently attacking humans. Dogs and cats
can be used to attract fleas from the premises.
Recommended pet treatments at frequent inter-
vals will then kill the fleas.
Pesticidal premise treatment is divided into dif-
ferent areas to concentrate applications-house-
hold and yards. Insecticides approved for use in
the home differ from those used in other areas.
The following insecticides are recommended for
household or yard premise treatment for fleas.
Treat Insecticide Comments
Household 2% malathion
+ 1% synergist
1% ronnel (Korlan)
2% Baygon dust
Fleas breed in
cracks of floors,
and beneath carpets.
Spot treat these
areas. For effec-
tive control treat
all areas frequented
by animals at the
same time the animal
is treated. Treat-
ment may be repeated
in 10-14 days to elim-
inate newly hatched
(Actual size 1/16" long)
Treat Insecticide Comments
Yards 2% carbaryl Read and follow label
(Sevin) spray directions.
In addition to the above procedures, indoor
misters and total release aerosols containing di-
chlorvos or pyrethrins may be used in conjunction
with residual spray to quickly reduce adult popu-
lation. Be sure to follow the label directions.
Certain people are more susceptible to fleas than
others. Sensitive people may wish to apply an in-
sect repellent containing DEET diethyll tolua-
mide) for protection in highly infested areas.
Several species of ticks attack dogs, but cats are
rarely infested. Many of the dog ticks are known
as wood ticks and infest dogs when they run
through the woods or fields. Ticks can also annoy
people but humans are not the preferred host.
Ticks are mites, not insects, and are closely re-
lated to the spiders. Adult ticks have eight legs.
All ticks are parasitic, feeding on the blood of
Of the ticks found in Florida, the brown dog
tick and the American dog tick are the most
troublesome. The brown dog tick rarely bites hu-
mans, but infestations are frequently found on
dogs and in the home. The American dog tick at-
tacks a wide variety of hosts, including humans.
American Dog Tick
(Actual size 1/3" long)
Brown Dog Tick
(Actual size 1/3" long)
The brown dog tick seldom attacks animals
other than dogs. It is most likely found where
dogs are kept in or around the house. The brown
dog tick is not known to transmit diseases to hu-
mans but may transmit disease among dogs.
The adult female tick lays a mass of 1,000-3,000
eggs after engorging on a dog's blood. These eggs
are often found in cracks on the roof of kennels
or high on the walls or ceilings of buildings. In the
house eggs are laid around baseboards, window
and door casings, curtains, furniture and edges of
rugs. The egg laying females are often seen going
up walls to lay eggs.
The eggs hatch in 19 to 60 days into a six-
legged, small seed tick. The seed tick takes a blood
meal from dogs when they are available. The lar-
vae are so small they won't be noticed on the dog
unless a number are together. The seed tick re-
mains attached for 3-6 days, turns bluish in color,
and then drops to the floor. After dropping from
the host, the seed tick hides for 6 to 23 days be-
fore molting into an eight-legged, reddish-brown
nymph. It is now ready for another blood meal
and again seeks a dog host. The nymphs attach to
dogs, drop off, and molt to the adult in 12 to 29
days. As a reddish-brown adult, it again seeks a
blood meal, becomes engorged and is bluish in
color, reaching about 1/3 inch in length.
Unengorged larvae, nymphs and adults may live
for long periods of time without a blood meal.
Adults have been known to live for as long as
200 days without a blood meal. Indoors, ticks
hiding between blood meals may be found behind
baseboards, window casings, window curtains,
bookcases, inside upholstered furniture and under
edges of rugs. Outdoors, ticks hide near founda-
tions of buildings, in crevices of siding or beneath
The American dog tick is also a common pest
of pets and humans in Florida. The adult males
and females are frequently encountered by sports-
men and people who work outdoors. Dogs are the
preferred host, although the American dog tick
will feed on other warm-blooded animals. The
nymphal stages of the American dog tick usually
only attack rodents. For this reason the American
dog tick is not considered a household pest.
The female dog tick lays 4,000 to 6,500 eggs
and then dies. The eggs hatch into seed ticks in
36 to 57 days The unfed larvae crawl in search of
a host and can live 540 days without food. When a
small rodent is found, the larvae attach and feed
for approximately five days. The larvae then drop
off the host and molt to the nymphal stage. The
nymphs crawl about in search of a rodent host,
attach to a suitable host, and engorge with blood
in 3 to 11 days. Nymphs can live without food for
up to 584 days.
Adults crawl about in search of dogs or large
animals for a blood meal. Adults can live for up
to two years without food. American dog tick
adults and many other species can be found along
roads, paths, and trails, on grass and other low
vegetation in a "waiting position." As an animal
passes by, the tick will grasp firmly and soon start
feeding on its host. The males remain on the host
for an indefinite period of time alternately feeding
and mating. The females feed, mate, become en-
gorged and then drop off to lay their eggs.
The American dog tick requires from three
months to three years to complete a life cycle. It
is typically an outdoor tick and is dependent on
climatic and environmental conditions for the eggs
Importance of Ticks
When feeding, ticks make a small hole in the
skin, attach themselves with a modification of one
of the mouthparts which has teeth that curve
backwards, and insert barbed piercing mouthparts
to remove blood.
The presence of ticks is annoying to dogs and
humans. Heavy continuous infestations on dogs
cause irritation and loss of vitality. Pulling ticks
off the host may leave a running wound which
may become infected because of their type of at-
The brown dog tick is not a vector of human di-
sease, but it is capable of transmitting canine pi-
roplasmosis among dogs.
The American dog tick may carry Rocky Moun-
tain spotted fever, tularemia and other diseases
from animals to people. Dogs are not affected by
these diseases, but people have become infected
by picking ticks from dogs. People living in areas
where these wood ticks occur should inspect them-
selves several times a day. Early removal is im-
portant since disease organisms are not trans-
ferred until the tick has fed for several hours.
The American dog tick is also -known to cause
paralysis in dogs and children where ticks attach
at the base of the skull or along the spinal column.
Paraylsis is caused by a toxic secretion produced
by the feeding tick. When the tick is removed, re-
covery is rapid, usually within eight hours. Sensi-
tized animals may become paralyzed by tick at-
tachment anywhere on the body.
Ticks should be removed from pets and humans
as soon as they are noticed. Ticks should be re-
moved carefully and slowly. If the attached tick
is broken, the mouthparts left in the skin may
transmit disease or cause secondary infection.
Ticks may easily be removed by touching the tick
with a hot needle or alcohol to relax it. Then grasp
the tick firmly with tweezers or fingers near the
mouthparts and pull evenly and firmly. A small
amount of flesh should be seen attached to the
mouthparts after the tick is removed.
Pesticidal control of ticks may require both pet
treatment and treatment of the infested area. If
a heavy tick infestation occurs it is necessary to
treat pets, home and yard at the same time.
Pets may be treated with the following insecti-
5%/ carbaryl (Sevin) dust Do not use Sevin dust on
cats under 4 weeks old.
.5% coumaphos (Co-Ral) Do not use coumaphos on
dust dogs under 7 months old;
do not use on cats. Do not
use in combination with
other pesticides or drugs.
3-5% malathion dust Follow label directions.
.25% malathion dip
.5%, malathion wash
Rub dusts into the fur to the skin being careful
not to allow chemicals to get into the eyes, nose
or mouth. Heavy infestations of ticks on the ani-
mal should be controlled by dipping.
Brown dog tick infestations of homes and yards
are frequently difficult to control. Insecticides
should be applied inside the house carefully as
light, spot treatments to areas where ticks are
known to be hiding. Special effort should be given
in treating areas frequented by pets. Applications
at two to four week intervals may be necessary to
eliminate the ticks. Pets should be kept off treated
surfaces until dry.
The following chemicals may be used to treat
either the house or the yard.
Treat Insecticide Comments
Household 1% Baygon Spot treat all
.5% diazinon infested areas
.5% chlorpyrifos thoroughly. Treat
(Dursban) baseboards, floors,
2% malathion wall cracks and
.5% dichlorvos other hiding
(Vapona) places. Follow
1% ronnel label recommenda-
Yards 25% diazinon EC 3-6 fl oz in 15-20
gal per 500 sq ft.
chlorpyrifos Apply according to
(Dursban) label directions.
50% carbaryl 1.5 oz in 15-20 gal
(Sevin)WP per 500 sq ft.
People entering tick infested areas should keep
clothing buttoned, shirts inside trousers, and
trousers inside boots. Do not sit on the ground or
on logs in bushy areas. Keep brush cleared or
burned along frequently traveled areas. Repellents
such as DEET diethyll toluamide), methyl phtha-
late, dimethyl carbate or ethyl hexandiol will pro-
tect exposed skin. However, ticks will crawl over
treated skin to untreated parts of the body.
Mange is an unsightly and painful condition
caused by burrowing mange mites. Mange is con-
tagious and is spread by contact from infested
to non-infested animals.
Sarcoptic mange of dogs is related to the hu-
man skin disease called scabies. Dog mange is
caused by the canine mange mite which frequently
also attacks man. A closely related mite attacks
cats and produces a severe mange in felines.
The female canine mange mite burrows in the
upper layers of skin and lays 20 to 40 eggs singu-
larly which hatch in 3 to 5 days. The larvae molt
to the nymphal stage. The nymphs mature to
adults. The larvae, nymphs and adult male mites
live under scales on the skin surface and do not
burrow. The entire life cycle is completed in 8 to
Canine mange first appears on dogs as reddish,
inflamed papules on the edges of the ears, in the
groin or armpits. Usually symptoms first appear
on the head. Red spots appear and burrowing fe-
male mites cause the skin to exude serum which
dries to form scabs and crusts. The scratching of
the animal causes the infected area to spread
rapidly. Infested areas become dry, hair falls out,
the skin thickens and wrinkles. Irritation from the
scratching often leads to secondary infection
causing an unpleasant characteristic odor. If un-
treated, the animal may die of exhaustion, dehy-
dration, or from secondary infection.
Canine mange in humans (seven year itch) is
characterized by a rash developing after contact
with an infected dog. The eruption usually appears
as pimples but also may appear as blisters and
inflammation. Mange symptoms generally appear
on the forearms, thighs and abdomen, but may
occur in areas not infested by mites. This is an
immune response disease with some individuals
reacting more severely than others.
Feline mange usually starts on the heads of
cats forming crusts, causing the skin to thicken
Dogs and cats exhibiting mange symptoms
should be taken to a veterinarian for treatment.
Mange symptoms are often confused with flea
bite reactions. Humans with canine mange should
consult a physician
Red mange or demodectic mange of dogs is
caused by a mite which lives in the hair follicles
of the skin. The first evidence of red mange is the
appearance of bald areas where hair has fallen
out. As the bald area spreads, itching and irrita-
tion increases. Bacterial infections are usually as-
sociated with red mange and produce a foul odor.
Red mange usually weakens the animal exposing
it to other diseases which then kill the animal.
Many animals will self cure. The disease is most
common in dogs from 3 months to 11/2 years old.
Stressed animals often exhibit mange symptoms.
The most effective control is ronnel (Ectoral) as
applied by veterinarians.
/ \ \ (Actual size 1/14" long)
Ear mange is common among dogs, cats and
rabbits. The mites do not burrow in the skin but
live deep in the ear canal and feed on skin. The
resulting irritation causes the ear canal to become
congested. The affected animal rubs its ears and
shakes its head to relieve the itching.
Ear mange may be treated by applying mineral
oil to the ear canal with a medicine dropper or
cotton swab and by cleaning accumulations of
Proper care and the maintenance of good health
will increase a pet's resistance to skin disease.
Canine mange mainly occurs on young animals
which are undernourished and suffering from in-
ternal parasites and mothered by infested animals.
Pets should not be permitted to mingle with
mangy animals or contact premises occupied by
them since individual contact is the most impor-
tant method of transmission.
In almost all cases of mange on pets a veteri-
narian should be consulted.
PRECAUTIONS IN PESTICIDE APPLICATION
Although pesticides are used to protect animals
from pests, it is important to remember that any
pesticide should be considered an active poison.
It should never be allowed to get in or on feed or
water. The successful control of pests requires
careful mixing and application of pesticides ac-
cording to label directions. It is also essential to
use the right pesticide for the job and to apply it
no more frequently than recommended.
Never use more insecticide than is recom-
mended. Overdoses of pesticides are not only po-
tentially fatal, but also can weaken animals and
predispose them to disease. Young animals, be-
cause of their low body weight are particularly
susceptible to overdoses of some pesticides. Par-
ticular breeds of animals may also be sensitive to
some pesticides or pesticide formulations.
Many pests can be controlled by applying small
quantities of pesticides to specific areas of the in-
fested animal. In general pesticides should not be
used in combination with other pesticides or drugs
because the combination may produce undesir-
This publication was promulgated at a cost of $441.49, or 4.4
cents per copy, to inform the general public on three pests of
importance to them.
COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
Cooperative Extension Service, IFAS, University of Florida
and United States Department of Agriculture, Cooperating
K. R. Tefertiller, Director
Single copies are free to residents of Florida and may be obtained from the County Extension Office. Bulk rates are available upon
request. Please submit details of the request to C.M. Hinton, Publication Distribution Center, IFAS Building 664, University of Florida,
Gainesville, Florida 32611.