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Rabies is caused by a virus.
A virus cannot reproduce on its own. It “high jacks” a cell of a host and makes that cell produce more viruses!

 Shaped somewhat like a bullet.

 Rabies is a special virus because it is lethal to pets and people.
 All states require pets to be vaccinated for rabies.

All mammals are susceptible to rabies. This not only includes dogs and cats but livestock and humans as well.
Rabies is know as a zoonotic disease since it can affect both humans and animals.
In U.S. 93% of all rabies occurs in wild animals

 Why do we worry so much about rabies?
 What is a zoonotic disease?
 What kinds of animals get rabies?
 How does the rabies virus reproduce?

 Rabies is transmitted through the saliva of an infected animal. This usually occurs by a bite wound.
 The virus then travels up the nerves toward the brain and spinal cord. It even leaves one nerve cell and moves to the next. How do you suppose it does that?

 In early stages rabies is very difficult to detect.
 After an animal is bitten it usually takes two to twelve weeks before it shows any symptoms, however it may take as long as two years.
 This period of time is known as the incubation period.
Do I look like I have rabies?

 The first symptoms are flu- like. Human patients complain of feeling tired with pain and stiffness.

 Soon afterwards, symptoms begin to include neurological dysfunction (problems with the brain and nerves).
 This may include slight paralysis, anxiety, sleeplessness, paranoia, and delirium.

 In addition to neurological symptoms the patient will begin to produce large quantities of saliva and tears. The ability to swallow and speak are also lost.
 It is because of these characteristic symptoms that animals often “foam at the mouth.”

 Because patients are unable to swallow water they exhibit hydrophobia or fear of water.
 This is seen in approximately 50-80% of patients.

 The virus spreads from the brain to the salivary glands where viral particles are able to be shed in the saliva, thus allowing the animal to spread the virus to others.

 Rabid animals may also exhibit aggressive behavior. This makes them more likely to bite other animals allowing infection to spread.

 Once the onset of symptoms has begun the animal usually dies within ten days.
 Rabies is almost always fatal.
 There are only six reported cases in all of human history of humans surviving rabies after the onset of symptoms.

 What is happening during the incubation period of rabies?
 Summarize the symptoms of rabies.
 Why do bites spread rabies?

 Despite the fact that rabies is nearly always fatal once an animal is infected, it can be easily prevented.
 Vaccination is the most effective and commonly utilized method of prevention.
 Vaccinations are commonly given to pets and livestock.
 This method of prevention has greatly reduced the incidence of disease in many countries.

The first human was successfully vaccinated for rabies in 1885 after being bitten by a rabid dog.
While human vaccination has been available for many years, vaccination is normally only given to people who are exposed to a rabid animal or those who are at an increased risk of being exposed, such as veterinarians and animal care workers.

 Rabies is found in nearly all nations.
 Nations highlighted in red were at a high risk for rabies.
 The majority (99%) of rabies in humans is seen in Asia and
Africa.
Is the United States at high risk for Rabies?

Remember: rabies was such a big problem in France in the 1800s that it caused Pasteur to make a vaccine for rabies one of his highest priorities.
Pasteur biographies for kids

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The majority of rabies cases in the U.S. are caused by bats. Skunks and raccoons are also a major reservoir for the disease.
 Bat bites cause the largest number fatalities since the bites are often small and people may not even realize that they have been bitten.

Different colors for the same wild animal reservoir indicate a different variant of the rabies virus.
Source: JAVMA. 2008. 233: 884-897
How do you interpret the graph?

Wild Animal Sources
Texas
Raccoons Bats
17 482
Virginia 359
New York 279
North
Carolina
245
30
104
34
Skunks Foxes
362 32
185
75
98
90
25
58

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Never handle wild animals, especially skunks, raccoons and bats.
Never try to nurse sick animals back to health, call your local wildlife rescue service instead
Make sure wild animals can’t get into your garbage cans.
Never purposely feed wild animals.
Never handle wild animals that are acting unafraid of humans.
Never handle wild animals that approach you.
We’re cute, but we could be dangerous!

 Because rabies is such a deadly disease, testing is very important.
 If a wild animal bites a person, the animal should usually be tested immediately.
 If an person is bitten by a pet, the pet is put in quarantine for a period of ten days to see if it develops symptoms.
 If an animal is shedding the virus in its saliva it will almost always start showing symptoms within ten days.

Pets are kept away from all human contact during this time, and watched carefully by a veterinarian.

 Since rabies affects the brain the best way to test for it is by examining brain tissue.
 This is done with a method call direct fluorescent antibody testing.
 This test can only be done post mortem (after the animal is dead.)

 Always vaccinate your pets!
 Puppies and kittens should be vaccinated at sixteen weeks of age and then at one year of age.
 Every animal should get a vaccine every three years for the rest of their life.
 In Texas, pet rabies vaccination is required by state law!
Vaccinate us so we will be
SAFE!

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What are some things YOU can do to prevent getting exposed to rabies?

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Most research is focused on public health (vaccines in food for wild animals, better vaccines, vaccination programs for pets, etc.)
 We Need:
 More fundamental research on how a virus is able to multiply.
 Research on stopping the migration of rabies throughout the nervous system.

World Rabies Day is a worldwide campaign against rabies. One person in the world dies from rabies every 10
MINUTES, equaling 55,000 each year!
The disease is 100% fatal, but 100% preventable. Human deaths are happening most frequently in underprivileged countries, but the presence of rabies and it's risks are still remarkably high even in the U.S.
For more information go to: http://www.worldrabiesday.org/