Rabies Virus

 

Introduction:

Rabies is a deadly virus spread to people from the saliva of infected animals. The rabies virus is usually transmitted through a bite.

 

Animals most likely to transmit rabies in the United States include bats, coyotes, foxes, raccoons and skunks. In developing countries, stray dogs are the most likely to spread rabies to people.

Rabies is a viral disease that causes inflammation of the brain in humans and other mammals.Early symptoms can include fever and tingling at the site of exposure.These symptoms are followed by one or more of the following symptoms: nausea, vomiting, violent movements, uncontrolled excitement, fear of water, an inability to move parts of the body, confusion, and loss of consciousness.Once symptoms appear, the result is virtually always death, regardless of treatment. The time period between contracting the disease and the start of symptoms is usually one to three months but can vary from less than one week to more than one year.The time depends on the distance the virus must travel along peripheral nerves to reach the central nervous system.

 

Symptoms:

After a rabies exposure, the rabies virus has to travel to the brain before it can cause symptoms. This time between exposure and appearance of symptoms is the incubation period. It may last for weeks to months. The incubation period may vary based on

 

the location of the exposure site (how far away it is from the brain),

the type of rabies virus, and

any existing immunity.

The first symptoms of rabies may be similar to the flu, including weakness or discomfort, fever, or headache. There also may be discomfort, prickling, or an itching sensation at the site of the bite. These symptoms may last for days.

 

Symptoms then progress to cerebral dysfunction, anxiety, confusion, and agitation. As the disease progresses, the person may experience delirium, abnormal behavior, hallucinations, hydrophobia (fear of water), and insomnia. The acute period of disease typically ends after 2 to 10 days. Once clinical signs of rabies appear, the disease is nearly always fatal, and treatment is typically supportive. Less than 20 cases of human survival from clinical rabies have been documented. Only a few survivors had no history of pre- or postexposure prophylaxis.

 

The signs, symptoms, and outcome of rabies in animals can vary. Symptoms in animals are often similar to those in humans. These include early nonspecific symptoms, acute neurologic symptoms, and ultimately death

 

 

ater signs and symptoms may include:

 

Fever

Headache

Nausea

Vomiting

Agitation

Anxiety

Confusion

Hyperactivity

Difficulty swallowing

Excessive salivation

Fear brought on by attempts to drink fluids because of difficulty swallowing water

Fear brought on by air blown on the face

Hallucinations

Insomnia

Partial paralysis.

 

Causes:

The rabies virus causes a rabies infection. The virus spreads through the saliva of infected animals. Infected animals can spread the virus by biting another animal or a person.

 

In rare cases, rabies can be spread when infected saliva gets into an open wound or the mucous membranes, such as the mouth or eyes. This could happen if an infected animal licked an open cut on your skin.

 

 

Animals that can transmit the rabies virus:

Any mammal (an animal that suckles its young) can spread the rabies virus. The animals most likely to spread the rabies virus to people include:

 

Pets and farm animals

Cats

Cows

Dogs

Ferrets

Goats

Horses

 

Wild animals

Bats

Beavers

Coyotes

Foxes

Monkeys

Raccoons

Skunks

Woodchucks

In very rare cases, the virus has been spread to tissue and organ transplant recipients from an infected organ.

 

Risk factors:

Factors that can increase your risk of rabies include:

 

•Traveling or living in developing countries where rabies is more common

•Activities that are likely to put you in contact with wild animals that may have rabies, such as exploring caves where bats live or camping without taking precautions to keep wild animals away from your campsite

•Working as a veterinarian

•Working in a laboratory with the rabies virus

•Wounds to the head or neck, which may help the rabies virus travel to your brain more quickly.

 

 

Treatment:

If you've been bitten by an animal that is known to have rabies, you'll receive a series of shots to prevent the rabies virus from infecting you. If the animal that bit you can't be found, it may be safest to assume that the animal has rabies. But this will depend on several factors, such as the type of animal and the situation in which the bite occurred.

 

Rabies shots include:

 

A fast-acting shot (rabies immune globulin) to prevent the virus from infecting you. This is given if you haven't had the rabies vaccine. This injection is given near the area where the animal bit you if possible, as soon as possible after the bite.

A series of rabies vaccinations to help your body learn to identify and fight the rabies virus. Rabies vaccinations are given as injections in your arm. If you haven't previously had the rabies vaccines, you'll receive four injections over 14 days. If you have had the rabies vaccine, you'll have two injections over the first three days.