Dog - Rabies

What causes rabies?

Rabies is caused by a virus which is transmitted by the bite of an infected animal. It can affect most warm blooded animals and is almost always fatal, both to dogs and humans infected from the bite of a rabid dog.

It is a disease of antiquity, the danger from the bite of a mad dog was known even in the 23rd century BC.

Is the disease widespread?

Rabies occurs in every continent with the exception of Australia and Antarctica. Unaffected countries are usually islands or 'almost' islands. They include Great Britain, Ireland, Japan, Norway, Sweden and the Iberian peninsula.

How is the virus spread?

Rabies virus does not survive very long away from the body. It is also very sensitive to disinfectants and even soap and water. Infection is maintained by infected animals biting others. In Europe foxes are the main reservoir while in North America skunks, racoons and bats are important. In Asia, Africa and Latin America the main reservoir is not wildlife but stray, free living dogs. It is in these areas that infection of man is more common.

How long is the incubation period?

Incubation period is the time from exposure (being bitten) to the development of clinical signs. This can vary from two weeks to six months or even more. Once it has entered the body of a susceptible host via a bite, spread is not via the blood stream but by the virus entering nerves in which it multiplies and makes its way to the brain and spinal cord. The speed at which clinical signs develop depends upon:

• The site of infection, the nearer the bite is to the brain and spinal cord, the sooner clinical signs are apparent
• The severity of the bite
• The quantity of virus injected at the time of the bite

What are the clinical signs?

The first sign of rabies in an infected animal is a marked change in temperament. Quiet dogs become agitated and active friendly extroverts frequently become nervous, shy or aggressive.

There are then two recognised forms of the clinical disease:

1. Furious rabies. The dog becomes highly excitable and sometimes will display a depraved appetite, eating and chewing stones, earth and rubbish (pica). Paralysis usually then sets in and the dog may be unable to swallow and so cannot eat or drink. Hydrophobia (fear of water) is not a sign of the disease in dogs but does occur frequently following infection in man. The dog usually dies in a violent seizure.
2. Dumb rabies. This type occurs more commonly. It involves progressive paralysis of the limbs, distortion of the face and an inability to swallow. Owners will frequently report that the dog has something stuck in the mouth or throat. Care must be taken in examination since the saliva is infected. Ultimately the dog becomes comatose and dies.

Is it possible to survive a bite from a rabid animal?

There are isolated reports of both dogs and people surviving but without vaccination the chances are poor.

Is vaccination effective?

Circulating antibodies as a result of vaccination must be adequate before any virus enters the nervous system. Boosters must also be administered at least according to the vaccine manufacturers’ recommendations although some countries involved with the PETS (pet travel) scheme insist that any dogs travelling under PETS are boosted annually despite the fact that the manufacturers’ recommendations may indicate a booster every two or even three years.

Is there any treatment available?

There is no effective treatment for a dog with rabies. In the UK, if the disease is suspected the dog has to be kept in isolation, prevented from escaping or injuring anyone and DEFRA notified immediately. DEFRA will then arrange euthanasia and post mortem examination.

Can I be infected if bitten by a rabid dog?

Yes, the disease is zoonotic (i.e. can be transmitted to man). The virus is present in the saliva of the infected dog but is only present for a limited time.

If you are bitten by any animal that may be suspect, i.e. stray or feral dogs abroad, etc. you should immediately wash the wound very thoroughly with soap and water and seek medical advice of a doctor without delay.

Treatment with serum or vaccine may be recommended and is very successful if commenced without undue delay.

Can my dog be vaccinated against rabies?

With the introduction of the Pets Passport and PETS travel scheme, rabies vaccination is now available for any dog in the United Kingdom and is mandatory, together with certain other requirements, including microchipping, if you wish to travel with your dog to participating countries and return to Britain without the need for your dog to undergo quarantine.

If you require further details, please contact us and request the PETS handout.