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About Rabies
Rabies is one of the oldest known deadly viral diseases, yet
today it continues to remain a significant public health issue.
Rabies affects the central nervous system of unvaccinated
animals, including humans, that are exposed to the virus and
unless treated is ultimately fatal. Rabies is a
preventable viral disease of mammals most often transmitted
through the bite of a rabid animal.
Over the past 30 years, management of rabies in the United
States has shifted in focus from domestic pets being primary
carriers to wild animals as being the vector reservoirs
(including: skunks, foxes, raccoons, coyotes, bats).
According to the Centers for Disease Control and
Prevention (www.cdc.gov),
wildlife currently account for at least 90 percent of all
reported cases of rabies in the country.
Rabies virus infects the central nervous system, causing
encephalopathy and ultimately death. Early symptoms of rabies in
humans are nonspecific, consisting of fever, headache, and
general malaise. As the disease progresses, neurological
symptoms appear and may include insomnia, anxiety, confusion,
slight or partial paralysis, excitation, hallucinations,
agitation, hyper salivation, difficulty swallowing, and
hydrophobia (fear of water). Death usually occurs within days of
the onset of symptoms.
Because rabies is a fatal disease, the goal of public health is,
first, to prevent human exposure to rabies by education and,
second, to prevent the disease by anti-rabies treatment if
exposure occurs. Tens of thousands of people are successfully
treated each year after being bitten by an animal that may have
rabies. A few people die of rabies each year in the United
States, usually because they do not recognize the risk of rabies
from the bite of a wild animal and do not seek medical advice.
In Wyoming, the predominant types of rabies for the terrestrial
species (skunks and other mammals) is the North Central Skunk
Strain. Each species of bat carries their own type of the
virus, but the most identified strain is the Silver Haired Bat
virus.
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Frequently Asked Questions
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Pets
How can I protect my pet from rabies?
There are several things you can do to protect your pet from
rabies. First, visit your veterinarian with your pet on a
regular basis and keep rabies vaccinations up-to-date for all
cats, ferrets, and dogs. Second, maintain control of your pets
by keeping cats and ferrets indoors and keeping dogs under
direct supervision. Third, spay or neuter your pets to help
reduce the number of unwanted pets that may not be properly
cared for or vaccinated regularly. Lastly, call animal control
to remove all stray animals from your neighborhood since these
animals may be unvaccinated or ill.
Why does my pet need the rabies vaccine?
Although the majority of rabies cases occur in wildlife, most
humans are given rabies vaccine as a result of exposure to
domestic animals. This explains the tremendous cost of rabies
prevention in domestic animals in the United States. While
wildlife are more likely to be rabid than are domestic animals
in the United States, the amount of human contact with domestic
animals greatly exceeds the amount of contact with wildlife.
Your pets and other domestic animals can be infected when they
are bitten by rabid wild animals. When "spillover" rabies occurs
in domestic animals, the risk to humans is increased. Pets are
therefore vaccinated by your veterinarian to prevent them from
acquiring the disease from wildlife, and thereby transmitting it
to humans
What happens if a neighborhood cat bites me?
You should seek medical evaluation for any animal bite. However,
rabies is uncommon in dogs, cats, and ferrets in the United
States. Very few bites by these animals carry a risk of rabies.
If the cat (or dog or ferret) appeared healthy at the time you
were bitten, it can be confined by its owner for 10 days and
observed. No anti-rabies prophylaxis is needed. No person in the
United States has ever contracted rabies from a dog, cat or
ferret held in quarantine for 10 days.
If a dog, cat, or ferret appeared ill at the time it bit you or
becomes ill during the 10 day quarantine, it should be evaluated
by a veterinarian for signs of rabies and you should seek
medical advice about the need for anti-rabies prophylaxis.
The quarantine period is a precaution against the remote
possibility that an animal may appear healthy, but actually be
sick with rabies. To understand this statement, you have to
understand a few things about the pathogenesis of rabies (the
way the rabies virus affects the animal it infects). From
numerous studies conducted on rabid dogs, cats, and ferrets, we
know that rabies virus inoculated into a muscle travels from the
site of the inoculation to the brain by moving within nerves.
The animal does not appear ill during this time, which is called
the incubation period and which may last for weeks to months. A
bite by the animal during the incubation period does not carry a
risk of rabies because the virus is not in saliva. Only late in
the disease, after the virus has reached the brain and
multiplied there to cause an encephalitis (or inflammation of
the brain), does the virus move from the brain to the salivary
glands and saliva. Also at this time, after the virus has
multiplied in the brain, almost all animals begin to show the
first signs of rabies. Most of these signs are obvious to even
an untrained observer, but within a short period of time,
usually within 3 to 5 days, the virus has caused enough damage
to the brain that the animal begins to show unmistakable signs
of rabies. As an added precaution, the quarantine period is
lengthened to 10 days.
For more information on recommendations about biting incidences,
quarantine, and postexposure prophylaxis (PEP), see:
Compendium of
Animal Rabies Control, 2000 and
Rabies
Prevention - United States, 1999 Recommendations of the
Immunization Practices Advisory Committee (ACIP).
What happens if my pet (cat, dog, ferret) is bitten by a wild
animal?
Any animal bitten or scratched by either a wild, carnivorous
mammal or a bat that is not available for testing should be
regarded as having been exposed to rabies. Unvaccinated dogs,
cats, and ferrets exposed to a rabid animal should be euthanized
immediately. If the owner is unwilling to have this done, the
animal should be placed in strict isolation for 6 months and
vaccinated 1 month before being released. Animals with expired
vaccinations need to be evaluated on a case-by-case basis. Dogs
and cats that are currently vaccinated are kept under
observation for 45 days.
For information on rabies in domestic ferrets, see: Niezgoda,
M., Briggs, D. J., Shaddock, J., Dreesen, D. W., & Rupprecht, C.
E. (1997). Pathogenesis of experimentally induced
rabies in domestic ferrets. American Journal of
Veterinary Research, 58(11), 1327-1331.
I am moving to a rabies-free country and want to take my pets
with me. Where can I get more information?
The details of regulation about importing pets into rabies-free
countries vary by country. Check with the embassy of your
destination country.
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Human Rabies
How do people get rabies?
People usually get get rabies from the bite of a rabid animal.
It is also possible, but quite rare, that people may get rabies
if infectious material from a rabid animal, such as saliva, gets
directly into their eyes, nose, mouth, or a wound.
Can I get rabies in any way other than an animal bite?
Non-bite exposures to rabies are very rare. Scratches,
abrasions, open wounds, or mucous membranes contaminated with
saliva or other potentially infectious material (such as brain
tissue) from a rabid animal constitute non-bite exposures.
Occasionally reports of non-bite exposure are such that
postexposure prophylaxis is given.
Inhalation of aerosolized rabies virus is also a potential
non-bite route of exposure, but other than laboratory workers,
most people are unlikely to encounter an aerosol of rabies
virus.
Other contact, such as petting a rabid animal or contact with
the blood, urine or feces (e.g., guano) of a rabid animal, does
not constitute an exposure and is not an indication for
prophylaxis.
How soon after an exposure should I seek medical attention?
Medical assistance should be obtained as soon as possible after
an exposure. There have been no vaccine failures in the United
States (i.e., someone developed rabies) when postexposure
prophylaxis (PEP) was given promptly and appropriately after an
exposure.
What medical attention do I need if I am exposed to rabies?
One of the most effective methods to decrease the chances for
infection involves thorough washing of the wound with soap and
water. Specific medical attention for someone exposed to rabies
is called
postexposure
prophylaxis or PEP. In the United States,
postexposure prophylaxis consists of a regimen of one dose of
immune globulin and five doses of rabies vaccine over a 28-day
period. Rabies immune globulin and the first dose of rabies
vaccine should be given by your health care provider as soon as
possible after exposure. Additional doses or rabies vaccine
should be given on days 3, 7, 14, and 28 after the first
vaccination. Current vaccines are relatively painless and are
given in your arm, like a flu or tetanus vaccine.
Will the rabies vaccine make me sick?
Adverse reactions to rabies vaccine and immune globulin are not
common. Newer vaccines in use today cause fewer adverse
reactions than previously available vaccines. Mild, local
reactions to the rabies vaccine, such as pain, redness,
swelling, or itching at the injection site, have been reported.
Rarely, symptoms such as headache, nausea, abdominal pain,
muscle aches, and dizziness have been reported. Local pain
and low-grade fever may follow injection of rabies immune
globulin.
What if I cannot get rabies vaccine on the day I am supposed to
get my next dose?
Consult with your doctor or state or local public health
officials for recommended times if there is going to be a change
in the recommended schedule of shots. Rabies prevention is a
serious matter and changes should not be made in the schedule of
doses.
Can rabies be transmitted from one person to another?
The only documented cases of rabies caused by human-to-human
transmission occurred among 8 recipients of transplanted
corneas. Investigations revealed each of the donors had died of
an illness compatible with or proven to be rabies. The 8 cases
occurred in 5 countries: Thailand (2 cases), India (2 cases),
Iran (2 cases) the United States (1 case), and France (1 case).
Stringent guidelines for acceptance of donor corneas have
reduced this risk
In addition to transmission from corneal transplants, bite and
non-bite exposures inflicted by infected humans could
theoretically transmit rabies, but no such cases have been
documented. Casual contact, such as touching a person with
rabies or contact with non-infectious fluid or tissue (urine,
blood, feces) does not constitute an exposure and does not
require postexposure prophylaxis. In addition, contact
with someone who is receiving rabies vaccination does not
constitute rabies exposure and does not require postexposure
prophylaxis.
For more information on person-to-person transmission of rabies,
see: Fekadu, M., Endeshaw, T., Alemu, W., Bogale, Y., Teshager,
T., & Olson, J. G. (1996). Possible human-to-human
transmission of rabies in Ethiopia. Ethiopia Medical Journal,
34, 123-127.
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Wild Animals
What animals get rabies?
Any mammal can get rabies. The most common
wild reservoirs of rabies are raccoons, skunks, bats, foxes, and
coyotes. Domestic mammals can also get rabies. Cats, cattle, and
dogs are the most frequently reported rabid domestic animals in the
United States.
How can I find out what animals have rabies in my area?
Each state collects specific information about rabies, and is the
best source for information on rabies in your area. In addition, the
CDC publishes rabies surveillance data every year for the United
States. The report, entitled
Rabies
Surveillance in the United States, contains information
about the number of cases of rabies reported to CDC during the year,
the animals reported rabid, maps showing where cases were reported
for wild and domestic animals, and distribution maps showing
outbreaks of rabies associated with specific animals. A summary of
the report can be found in the
Epidemiology
section of this web site.
What is the risk of rabies from squirrels, mice, rats, and other
rodents?
Small rodents (such as squirrels, rats, mice, hamsters, guinea pigs,
gerbils, and chipmunks, ) and lagomorphs (such as rabbits and hares)
are almost never found to be infected with rabies and have not been
known to cause rabies among humans in the United States. Bites by
these animals are usually not considered a risk of rabies unless the
animal was sick or behaving in any unusual manner and rabies is
widespread in your area. However, from 1985 through 1994, woodchucks
accounted for 86% of the 368 cases of rabies among rodents reported
to CDC. Woodchucks or groundhogs (Marmota
monax)
are the only rodents that may be frequently submitted to state
health department because of a suspicion of rabies. In all cases
involving rodents, the state or local health department should be
consulted before a decision is made to initiate postexposure
prophylaxis (PEP).
For more information about rabies in rodents and lagomorphs,
see: Childs, J. E., Colby, L., Krebs, J. W., Strine, T., Feller,
M., Noah, D., Drenzek, C., Smith, J.S., & Rupprecht, C. E.
(1997). Surveillance and spatiotemporal associations of rabies
in rodents and lagomorphs in the United States, 1985-1994.
Journal of Wildlife Diseases, 33(1), 20-27.
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Bats and Rabies
Do bats get rabies?
Yes. Bats are mammals and are susceptible to rabies, but most do not
have the disease. You cannot tell if a bat has rabies just by
looking at it; rabies can be confirmed only by having the animal
tested in a laboratory. To minimize the risk for rabies, it is best
never to handle any bat.
What should I do if I come in contact with a bat?
If you are bitten by a bat -- or if infectious material (such as
saliva) from a bat gets into your eyes, nose, mouth, or a wound --
wash the affected area thoroughly and get medical attention
immediately. Whenever possible, the bat should be captured and sent
to a laboratory for rabies testing.
People usually know when they have been bitten by a bat. However,
because bats have small teeth which may leave marks that are not
easily seen, there are situations in which you should seek medical
advice even in the absence of an obvious bite wound. For example, if
you awaken and find a bat in your room, see a bat in the room of an
unattended child, or see a bat near a mentally impaired or
intoxicated person, seek medical advice and have the bat tested.
People cannot get rabies just from seeing a bat in an attic, in a
cave, or at a distance. In addition, people cannot get rabies from
having contact with bat guano (feces), blood, or urine, or from
touching a bat on its fur (even though bats should never be
handled!).
What should I do if I find a bat in my home?
If you see a bat in your home and you are sure no human or pet
exposure has occurred, confine the bat to a room by closing all
doors and windows leading out of the room except those to the
outside. The bat will probably leave soon. If not, it can be caught,
as described below, and released outdoors away from people and pets.
However, if there is any question of exposure, leave the bat alone
and call animal control or a wildlife conservation agency for
assistance. If professional assistance is unavailable, use
precautions to capture the bat safely, as described below.
What you will need:
leather work gloves (put them on)
small box or coffee can
piece of cardboard
tape
When the bat lands, approach it slowly and place a box or coffee can
over it. Slide the cardboard under the container to trap the bat
inside. Tape the cardboard to the container securely. Contact your
health department or animal control authority to make arrangements
for rabies testing.
How can I tell if a bat has rabies?
Rabies can be confirmed only in a laboratory. However, any bat that
is active by day, is found in a place where bats are not usually
seen (for example in rooms in your home or on the lawn), or is
unable to fly, is far more likely than others to be rabid. Such bats
are often the most easily approached. Therefore, it is best never to
handle any bat.
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Travel
Should I be concerned about rabies when I travel outside the United
States?
Yes. Rabies and the rabies-like viruses can occur in animals
anywhere in the world. In most countries, the risk of rabies in an
encounter with an animal and the precautions necessary to prevent
rabies are the same as they are in the United States. When
traveling, it is always prudent to avoid approaching any wild or
domestic animal.
The developing countries in Africa, Asia, and Latin America have
additional problems in that dog rabies is common there and
preventive treatment for human rabies may be difficult to obtain.
The importance of rabid dogs in these countries, where tens of
thousands of people die of the disease each year, cannot be
overstated. Unlike programs in developed countries, dog rabies
vaccination programs in developing countries have not always been
successful. Rates of postexposure prophylaxis in some developing
countries are about 10 times higher than in the United States, and
rates of human rabies are sometimes100 times higher. Before
traveling abroad, consult a health care provider, travel clinic, or
health department about your risk of exposure to rabies and how to
handle an exposure should it arise.
Should I receive rabies preexposure vaccination before traveling to
other countries?
In most countries, the risk of rabies and the precautions for
preventing rabies are the same as they are in the United States.
However, in some developing countries in Africa, Asia, and Latin
America, dog rabies may be common and preventive treatment for
rabies may be difficult to obtain. If you are traveling to a
rabies-endemic country, you should consult your health care provider
about the possibility of receiving preexposure vaccination against
rabies. Preexposure vaccination is suggested if:
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Your planned activity will bring you into contact with wild or
domestic animals (for example, biologists, veterinarians, or
agriculture specialists working with animals).
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You will be visiting remote areas where medical care is
difficult to obtain or may be delayed (for example, hiking
through remote villages where dogs are common).
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Your stay is longer than 1 month in an area where dog rabies is
common (the longer you stay, the greater the chance of an
encounter with an animal).
If I get preexposure vaccination before I travel, am I protected if
I am bitten?
No. Preexposure prophylaxis is given for several reasons. First,
although preexposure vaccination does not eliminate the need for
additional therapy after a rabies exposure, it simplifies therapy by
eliminating the need for human rabies immune globulin (HRIG) and
decreasing the number of doses needed – a point of particular
importance for persons at high risk of being exposed to rabies in
areas where immunizing products may not be readily available.
Second, it may protect persons whose postexposure therapy might be
delayed. Finally, it may provide partial protection to persons with
inapparent exposures to rabies.
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