Rage

Description of the virus

The rage is caused by a virus of the family of the Rhabdoviridae and kind Lyssavirus. They are wrapped viruses, their genome is a molecule of ARN (Ribonucleic acid) of negative polarity of helicoid form. For this reason (wrapped virus), they have a great sensitivity to the physicochemical agents of Désinfection and thus a low resistance in the external medium (the virus does not tolerate the temperatures from 38 to 40 [[degree Celsius °C]], it becomes inactive however once in little time in an organization it is protected).

The rabies virus infects all the mammals. It has a nervous tropism, and in particular the central Nervous system (SNC), which explains the disorders observed. Whatever the treatment, death is inescapable once the declared clinical signs.

Transmission and symptoms

An animal infected by the rabies virus can start to excrete it up to 15 days before the first clinical signs. The virus is then present in all secretions of the animal, including in its deposit. Considering its brittleness in the external medium, the entry of the virus in the organization is done only by the means of an effraction of the Peau or by the Muqueuse S oral or ocular.

The transmission in vitro can also be done by way Aérosol, via the mucous membranes; it is, for example what occurs in the caves inhabited by mad Chauve-souris: one reported two cases of speleologists having contracted the rage after having been in contact with mad Aérosol S coming from Chauve-souris… In a rarer way, the transmission can also intervene in a surgery by corneal transmission.

In Europe, the nonflying terrestrial vectors of the rage can be the fox, the wolf, the badger, the roe-deer but also the dog, the cat, the cow. In America, the rage is transmitted by the raccoon or the coyote. The rage is generally transmitted by bite, but can also be transmitted by simple licking. After an human infection, the virus penetrates (directly or indirectly) the peripheral Nervous system. He travels then along the Nerf S towards the central nervous system. During this phase it cannot be easily detected by the Immune system of the host, and vaccination can always confer an immunity. Once the virus reaches the Cerveau it causes a encéphalite quickly and the symptoms appear. It can also infect the Spinal-cord, causing a Myélite.

The incubation period is generally from three to twelve weeks but can reach two years. In the animal, the symptoms depend on the species concerned. Typically, one observes a Ataxie generalized, Hyperesthésie, pains cervical, a hypersalivation marked and sometimes of the convulsions of the facial muscles (as private individuals of the masséters). In the case of the carnivores, an abnormally aggressive behavior can be observed but is not systematic. In this case the animal seeks to bite any object being located near its head, and does not release not taken after bite. The barking of a mad dog is specific, bitonal. One thus systematically seeks to draw aside in first intention the rage when a dog comes in consultation with nervous disorders. One observes at the man of the disorders of the higher cerebral functions, anxiety, confusion, agitation, until reaching the Delirium , the behavioral problems, the Hallucination S and the Insomnie S. the production of great quantity of saliva and tears with difficulty of swallowing are typical advanced phases. Specifically at the man also at the end of the evolution a Hydrophobie develops: the sight of liquid causes a nonreasonable fear, whereas the contact involves feelings of insupportable burns. Death, inevitable, occurs from two to ten days after the primary symptoms.

According to I. Solomon, in a third of the cases, the disease takes the form of an ascending paralysis resembling the Syndrome of Guillain-Barred.

Prevention and treatment

The rage is a disease almost constantly mortal at the man when the first signs appear. The cases of survival are completely exceptional. On the contrary, the anti-rabic vaccination practiced between the contamination and the appearance of the first signs are very effective.

Preventive medication

A preventive vaccine against the rage exists. It is inoculated with the people whose activity is a risk factor of infection. The veterinary surgeons or the people going in certain countries as India are examples. This preventive vaccine does not exempt curative vaccination.

Curative vaccination

One can prevent the disease with the proviso of being caught there before the first signs do not appear, i.e. for the incubation period, by applying a curative Vaccination like showed it Louis Pasteur in 1885.

Knowing that the disease is most frequently transmitted by bite, but sometimes as by licking of wound or by scratch, and as it runs out between two and eight weeks before she declares herself, that leaves a reaction time. In fact the duration of the infection depends on the amount of Virus inoculated, of the localization of the bite (the closer it is to a zone rich in nervous terminations , more quickly the disease is declared) and of the gravity of the wound.

Recalls must be made regularly. It is useful to withdraw as much as possible the material infected after the bite if it is necessary.

When the disease is declared without preliminary vaccination, she generally synonymous with died: indeed, there are only five known cases of patients having survived thanks to a vaccination after the appearance of the Symptôme S.

However fine 2004, Wauwatosa in the Wisconsin, an experimental treatment made it possible to save without vaccination a young American teenager contaminated by a Chauve-souris. The treatment consists in plunging the patient in an artificial coma to slow down the progression of the disease and managing an intensive medical care to him.

Action to be taken in the presence of a case of rage or suspicion of rage

It is necessary to immediately announce any case of rage to the technical chief or the local administrative authority. Any dog mordor must be regarded as suspect of rage.

Action to be taken with regard to the dog mordor

It is very important to know that a few days before the observation of any symptom of the disease, the dog which becomes dangerous is able by its bite to transmit the rage. Also it is necessary to keep it in observation during at least 15 days. As a fourrière, the dog must be nourished and watered. After some time, if the dog is mad, he will die in the ten days. Any dog having bitten a person, even if it does not present any sign of rage, must be placed in observation. During this period of observation, if the signs of the disease appear, the rapid evolution of the fatal character of the evil make it possible to establish the diagnosis. One should not sacrifice a dog mordor as one is tempted to do it. By prudence, this one can thus deprive the possibility of knowing if it were truly mad…

Action to be taken with regard to the bitten person

When the symptoms of rage appear at the man it is too late to intervene: death is the only exit. This is why it is advisable to respect the following recommendations scrupulously:

When a person is bitten, either very deeply, or in many places of the body, or of face, or with the head, or with the neck, or with the fingers, this one must undergo the anti-rabic treatment as soon as possible even if the dog mordor does not present signs of rage and even if it were not in contact with a mad dog. This bitten person must make bleed the wound abundantly then to disinfect the wound with a disinfectant (potash permanganate, for example) and to take adapted antibiotics immediately, then to go in an health center in order to be made manage the antitetanus serum and the anti-rabic vaccine.

Infected zones

The disease would kill between: 40000 and: 70000 people each year throughout the world and these figures must be regarded as alarming.

In France, the last cases of rage on human beings, go back to 1924, however travellers can be contaminated abroad, in the countries at the risks, and return sick. The disease was regarded as disappeared since the beginning of the year 2001, although:

the disease still remains in an animal tank represented in particular by some Renard S of the north and the east of France, and by the bat, but it is very little probable that these animals transmit the virus to the man.
There is a permanent risk coming from the animals, in particular the Chien S, imported illegally, of the countries of the Europe of the East and the Morocco, in spite of the sanction envisaged to be condemned to five years of Prison and: 75000 Euro S of fine.

At the time of the summer 2004, a small bitch, named Tiki , imported illegally Morocco, the July 11th, like remembering stay, made blow a wave of panic in the south-west of the France. Died the August 21st, three days after having expressed the first signs of the disease, the bitch could have contaminated other animals or the human ones, with which it had been in contact during many displacements of its owner in the area. Under the effect of the disease, it would have caused bites on several occasions. Finally the whole of the people and animals threatened could be found and threatens it circumscribed.

For Switzerland, the country is recognized unscathed of rage since January 1st, 1999. The appearance by terrestrial way of case coming from wild animals is improbable. However, the cases of bat or imported animals carrying are not excluded. Moreover, in 2002, a case of infected bat was deferred on the canton of Geneva and in 2003 on the canton of Vaud, an imported dog of North Africa was declared positive.

Obligatory declaration

In Belgium, France and Switzerland, this disease is on the list of the Infectious illness to obligatory declaration.

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