Etiology and transmission
Rabies is an infectious, virulent and inoculable disease. The agent is a virus, called Lyssavirus of the Rhabdoviridae family, very fragile in the external environment. Rabies affects ALL mammals without exception, but we will consider rabies in dogs here.
It is contaminated by the saliva of a sick animal, by bite. The virus, on this occasion, passes into the traumatic lesion. It multiplies locally and reaches a nervous branch. By ascending route along the nerves it ends up reaching the brain where it multiplies actively. It then descends along the nerves to reach various organs (heart, skin, eye). The most important are the salivary glands where it continues to replicate. The blood does not contain viruses which prevents transmission by vectors (insects, ticks, etc.)
Symptoms and diagnosis
The incubation phase, which is very variable, on average from 15 to 60 days (around 6 months quarantine in the countries which practice it) can exceptionally be longer. Symptoms finally appear and the disease progresses in 4 to 5 days on average. In the days preceding the illness, and at most 8 days before, the virus will excrete in the saliva making the animal particularly dangerous.
“Everything is rage, nothing is rage” used to say an old adage. It is to say the polymorphism of the disease which goes from a “furious form” to a “paralytic form” with all the possible intermediaries.
Often the very first sign of rabies in dogs is a simple behavioral change, restlessness or apathy, sometimes a hallucinatory impression or a particular so-called bitonal bark … Hyperesthesia or pruritus are also classic. In dogs there is no hydrophobia. Finally appear little by little, sometimes immediately a paresis then a paralysis of the hindquarters, the jaws … The outcome is ALWAYS death.
The clinical picture, very varied and the uncharacteristic symptoms, are to be compared with a possible contamination: bite, trip abroad or contact with a dog coming from abroad.
Laboratory tests are necessary to confirm the disease: immunology, culture, etc.
Treatment and prophylaxis
As soon as the symptoms declare, there is NO treatment. In case of suspicion and BEFORE the first signs, repeated injection of serum uses.
Prophylaxis, which is very effective, involves vaccination.
Animal rabies is subject to mandatory declaration (Disease deemed legally contagious) which triggers a protocol aimed at identifying humans and animals that have been in contact with a rabid animal.
Risks in humans
If in Western Europe the disease is extremely rare, it is common in Africa and Asia, and exists in Central and South America and in Eastern Europe. In these countries there is rabies in wild animals and “street rabies”, meaning that a dog in the wild can transmit the disease. Rabies is responsible for 50 to 60,000 deaths per year. It is a very current disease, and 98% of human cases are due to a dog bite.
Humans are almost exclusively contaminated by the saliva of rabid animals with which they can come into contact by biting or simply licking if the skin is damaged. Other modes of transmission are exceptional (transplants, professional contact, inhalation). The virus being very fragile on the outside, indirect contamination does not exist.
The incubation phase of rabies, where it is possible to prevent human disease, is longer the closer the bite is to one extremity.
In practice it will be necessary to retain
- In the event of a bite by any animal or licking by an unknown animal. Consult a doctor to treat the bite and have the biting animal placed under surveillance, knowing that it can excrete virus through its saliva at most eight days before the first symptoms; identify the animal, registration being compulsory. If the owner refuses to carry out the 3 legal inspections. As soon as possible after the bite, 8 and 15 days after – call in the police.
At the end of the period, the dog had no symptoms: No action to take.
So, if he dies, samples should take to verify the cause of death. If he is rabid, an investigation will launch to find humans and animals that have been in contact with him.
- If you are planning a trip abroad with your animal, especially outside the European Union, check with the Embassies of the countries concerned to find out the procedures specific to each country, the minimum being registration, possession of a passport and rabies vaccination – think about it 3 months before -. Logic would not get ANY dog area at risk, especially in Africa.
- Do NOT take or buy dog of unknown provenance that could pass (Africa) or be high (Eastern Europe) in rabies enzootic areas. This import is illegal.
- In the event of a bite, contact the health authorities.
- NEVER bring back – illegally – an animal.
In conclusion, all the cases of rabies declared in recent years have been in imported dogs. In view of the enormous human risk, we must be vigilant and scrupulously respect the regulations in force. This is the only way to keep our country free from rabies.