Rabies

Rabies is potentially deadly disease that is mainly transmitted through the bite of a rabid animal, according to the Centers for Disease Control and Prevention (CDC). (Read about "Animal & Insect Borne Diseases") CDC says about 90 percent of all rabies cases reported each year involve wild animals like bats, foxes, skunks and raccoons. Dogs, cats and cattle account for less than 10 percent of the reported rabies cases. Rabies kills more than 50-thousand people and millions of animals around the world each year, according to CDC. In the United States, the number of rabies-related human deaths has declined from more than 100 annually in the early 1900's to an average of one or two per year.

Symptoms

The rabies' virus infects the peripheral and central nervous system. (Read about "Nervous System") It causes acute encephalitis or brain inflammation (Read about "Encephalitis and Meningitis" "The Brain"), and it can be fatal if untreated.

According to CDC, early symptoms of rabies in humans are flu-like and typically consist of:

• fever
• headache
• general malaise

Later, neurological symptoms appear and may include:

• insomnia (Read about "Sleep")
• hallucinations
• confusion
• anxiety (Read about "Anxiety")
• slight or partial paralysis
• agitation
• excitation
• hypersalivation
• difficulty swallowing

CDC says death usually occurs days after symptoms begin. Most human deaths in the United States, in recent years, have been the result of the individual not seeking medical attention because they were unaware they had been infected.

Transmission

CDC says the rabies virus is usually passed to an uninfected animal through the bite and the virus-containing saliva of the infected host. The incubation period may vary from a few days to several years, but is usually 1 to 3 months. Most human infection comes from domesticated animals, mainly dogs. Immunization of dogs for rabies has resulted in a massive drop in infections, says CDC.

Diagnosis

CDC says several tests are necessary to diagnose rabies in humans; no single test is sufficient. Tests are performed on samples of saliva, spinal fluid, serum and skin biopsies of hair follicles from the nape of the neck. (Read about "Laboratory Testing" "Biopsy")

The direct fluorescent antibody test (dFA) is most commonly used to detect rabies in animals. This test requires brain tissue from animals suspected of being rabid and can only be performed after the animal is dead, according to CDC.

CDC says fast and accurate diagnosis of rabies in humans and other animals is essential for proper treatment, and saving a patient from unnecessary physical and psychological trauma.

Treatment

Once the symptoms of rabies appear, there is no treatment for the disease. However, scientists have developed an effective rabies vaccine that provides immunity to rabies when administered after an exposure as well as protection before an exposure occurs, according to CDC. Pre-exposure vaccination is recommended for people in high risk groups, like veterinarians, animal handlers and some laboratory workers. Post-exposure prophylaxis is indicated for people who may have been exposed to a rabid animal. CDC says prompt medical attention is extremely important if you are exposed to a potentially infected animal.

Prevention

While the rabies vaccine can prevent rabies, CDC says there are a number of steps you can take in the fight against this infectious disease:

• Vaccinate pets such as dogs, cats and ferrets against rabies.
• Keep your pets well supervised.
• Do not handle wild animals.
• Call an animal control officer if you see an animal acting strangely.
• If you do get bitten by an animal, wash the wound with soap and water for at least 5 minutes and call a doctor.

Above all, if you suspect you have been infected by rabies, get medical help right away.

Related Information:

    Microorganisms