Rabies in the U.S.

*** Health and Safety Alert Bulletin ***

Raising Rabies Awareness

Rabies in the U.S.

Public Health Alert Notice of Rabies Outbreak in NM

What is Rabies?

The rabies virus is transmitted through saliva or brain/nervous system tissue. You can only get rabies by coming in contact with these specific bodily excretions and tissues.

It’s important to remember that rabies is a medical urgency but not an emergency. Decisions should not be delayed.

Wash any wounds immediately. One of the most effective ways to decrease the chance for infection is to wash the wound thoroughly with soap and water.

See your doctor for attention for any trauma due to an animal attack before considering the need for rabies vaccination.

Your doctor, possibly in consultation with your state or local health department, will decide if you need a rabies vaccination. Decisions to start vaccination, known as post exposure prophylaxis (PEP), will be based on your type of exposure and the animal you were exposed to, as well as laboratory and surveillance information for the geographic area where the exposure occurred.

In the United States, post exposure prophylaxis consists of a regimen of one dose of immune globulin and four doses of rabies vaccine over a 14-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, and 14 after the first vaccination. Current vaccines are relatively painless and are given in your arm, like a flu or tetanus vaccine.

Over the last 100 years, rabies in the United States has changed dramatically. More than 90% of all animal cases reported annually to CDC now occur in wildlife; before 1960 the majority was in domestic animals. The principal rabies hosts today are wild carnivores and bats.

The number of rabies-related human deaths in the United States has declined from more than 100 annually at the turn of the century to one or two per year in the 1990’s. Modern day prophylaxis has proven nearly 100% successful.

In the United States, human fatalities associated with rabies occur in people who fail to seek medical assistance, usually because they were unaware of their exposure.

Rabies virus becomes noninfectious when it dries out and when it is exposed to sunlight. Different environmental conditions affect the rate at which the virus becomes inactive, but in general, if the material containing the virus is dry, the virus can be considered noninfectious

What are the signs and symptoms of rabies?

The first symptoms of rabies may be very similar to those of the flu including general weakness or discomfort, fever, or headache. These symptoms may last for days.

There may be also discomfort or a prickling or itching sensation at the site of bite, progressing within days to symptoms of cerebral dysfunction, anxiety, confusion, agitation. As the disease progresses, the person may experience delirium, abnormal behavior, hallucinations, 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.

Disease prevention includes administration of both passive antibody, through an injection of human immune globulin and a round of injections with rabies vaccine.

Once a person begins to exhibit signs of the disease, survival is rare. To date less than 10 documented cases of human survival from clinical rabies have been reported and only two have not had a history of pre- or post exposure prophylaxis.

What to do with an animal that has bitten a person

Dogs, Cats, and Ferrets

Rabies virus might be excreted in the saliva of infected dogs, cats, and ferrets during illness and/or for only a few days before illness or death. A healthy dog, cat, or ferret that bites a person should be confined and observed daily for 10 days. Administration of rabies vaccine to the animal is not recommended during the observation period to avoid confusing signs of rabies with possible side effects of vaccination. Animals in confinement should be evaluated by a veterinarian at the first sign of illness. Any illness in the animal should be reported immediately to the local health department. If signs suggestive of rabies develop, the animal should be euthanized and the head shipped for testing. Any stray or unwanted dog, cat, or ferret that bites a person may be euthanized immediately and the head submitted for rabies examination.

Other Animals

Other biting animals that might have exposed a person to rabies should be reported immediately to the local health department. Management of animals other than dogs, cats, and ferrets depends on the species, the circumstances of the bite, and the epidemiology of rabies in the area, the biting animal’s history, current health status, and the animal’s potential for exposure to rabies. Previous vaccination of these animals might not preclude the necessity for euthanasia and testing

Skunks, raccoons, foxes and bats that bite humans should be euthanized and tested as soon as possible. The length of time between rabies virus appearing in the saliva and onset of symptoms is unknown for these animals and holding them for observation is not acceptable.

After exposure to wildlife in which rabies is suspected, prophylaxis is warranted in most circumstances. Because the period of rabies virus shedding in wild animal hybrids is unknown, these animals should be euthanized and tested rather than confined and observed when they bite humans.

Vaccination should be discontinued if tests of the involved animal are negative for rabies infection

CDC MAPS SHOWING GENERAL REPORTED RABIES CASES 2000-2011: BOTH WILD AND DOMESTIC ANIMALS.

WILD

DOMESTIC

 

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 a bat has bitten them. However, because bats have small teeth that 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 call your local animal control to have the bat captured and tested. Do not let the bat go.

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 animal control authority to make arrangements for rabies testing.

What type of exposure occurred?

Rabies is transmitted only when the virus is introduced into a bite wound, open cuts in skin, or onto mucous membranes such as the mouth or eyes.

Other factors to consider when evaluating a potential rabies exposure include the natural occurrence in the area, the biting animal’s history and current health status (e.g., abnormal behavior, signs of illness), and the potential for the animal to be exposed to rabies (e.g., presence of an unexplained wound or history of exposure to a rabid animal).

A currently vaccinated dog, cat, or ferret is unlikely to become infected with rabies.

When an exposure has occurred, the likelihood of rabies infection varies with the nature and extent of that exposure. Under most circumstances, two categories of exposure — bite and nonbite — should be considered.

Bite

Any penetration of the skin by teeth constitutes a bite exposure. All bites, regardless of body site, represent a potential risk of rabies transmission, but that risk varies with the species of biting animal, the anatomic site of the bite, and the severity of the wound.

Bites by some animals, such as bats, can inflict minor injury and thus be difficult to detect.

Was the bite from a provoked or an unprovoked attack? Bites inflicted on a person attempting to feed or handle an apparently healthy animal should generally be regarded as provoked. If it was an unprovoked attack, that’s more likely to indicate that the animal is rabid.

Non bite

The contamination of open wounds, abrasions, mucous membranes, or theoretically, scratches (potentially contaminated with infectious material from a rabid animal) constitutes a non bite exposure.

Non bite exposures from terrestrial animals rarely cause rabies. However, occasional reports of rabies transmission by non bite exposures suggest that such exposures should be evaluated for possible post exposure prophylaxis administration.

Other contact by itself, such as petting a rabid animal and contact with blood, urine, or feces of a rabid animal, does not constitute an exposure and is not an indication for post exposure vaccination.

Rabies PEP Vaccinations

Rabies PEP vaccinations consists of a dose of human rabies immune globulin and four doses of rabies vaccine given on the day of the exposure, and then again on days 3, 7, and 14. The vaccine is given in a muscle, usually in the upper arm. This set of vaccinations is highly effective at preventing rabies if given as soon as possible following an exposure.

If a person has previously received PEP vaccinations or received pre exposure vaccinations, only two doses of vaccine (on the day of exposure and then 3 days later) are needed. Human rabies immune globulin is not required. Your doctor and local health department will be able to guide you through the process.

For people who have never been vaccinated against rabies previously, PEP anti-rabies vaccination should always include administration of both passive antibody and vaccine.

The combination of human rabies immune globulin (HRIG) and vaccine is recommended for both bite and non bite exposures, regardless of the interval between exposure and initiation of treatment.

People who have been previously vaccinated or are receiving pre exposure vaccination for rabies should receive only vaccine.

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.

The vaccine should be given at recommended intervals for best results. Talk to your with your doctor or state or local public health officials if you will not be able to have shot at the recommended interval. Rabies prevention is a serious matter and changes should not be made in the schedule of doses.

People cannot transmit rabies to other people unless they themselves are sick with rabies. The prophylaxis you are receiving will protect you from developing rabies, and therefore you cannot expose other people to rabies. You should continue to participate in your normal activities.

Rabies Vaccines and Immunoglobulin Available in the United States

Type

Name

Route

Indications

Human Diploid Cell Vaccine (HDCV)

Imovax® Rabies Intramuscular Pre exposure or Post exposure

Purified Chick Embryo Cell Vaccine (PCEC)

RabAvert® Intramuscular Pre exposure or Post exposure

Human Rabies Immune Globulin

Imogam® Rabies-HT Local infusion at wound site, with additional amount intramuscular at site distant from vaccine Post exposure

Human Rabies Immune Globulin

HyperRab TM S/D Local infusion at wound site, with additional amount intramuscular at site distant from vaccine Post exposure

Remember, be careful around both Wild and Domestic animals of show any rabies signs. Safety First, Safety Always!

 Information from the CDC, World Book of Medical Encyclopedia and NM Dept of Health.

Today’s post comes to us courtesy of Ken Oswald
Safety and Security Manager for Plateau
koswald@plateautel.com