Familiarity with rabies

Rabies is a viral disease and one of the most important common diseases between humans and animals that mammals can contract. The rabies virus causes growth and lesions in the nervous system. Therefore, it is considered a nervous disease.

Most of the clinical symptoms that occur in rabies are related to the swelling caused by the virus in the brain, spinal cord and nerve roots. In general, clinical symptoms in animals appear in two ways: 1- The angry or crazy form of this type of animal disease becomes nervous and attacks other animals. 2- Paralyzed form in which the animal is paralyzed and relaxed and usually shelters in a corner. Therefore, the change in the natural behavior of animals should be considered as rabies infection. In other words, for example, if a jackal or a fox attacks a human or does not run away upon seeing a human, this is considered a change in the animal's natural behavior and should be considered as a sign of illness, and the same is true if a bat roosts during the day.

The study of ancient historical and medical texts shows that humans have been familiar with rabid dogs for a long time and had established laws and regulations to prevent them from biting humans, and based on these laws and regulations, dog owners were obliged to restrain them by tying and collaring them and accept the consequences of not restraining their dogs. However, in those days, people were not aware of the contagiousness and commonality of rabies between humans and animals, and they paid more attention to the injuries caused by angry dogs as a result of their bites. However, with the developments that occurred in the field of epidemiology in the 18th century, the infectiousness and the common nature of the disease were recognized, and the control and treatment of the disease became more important than the wound caused by the bite.

Rabies is endemic in most of the countries of Asia and Africa, and the most losses and casualties due to the disease are observed in these two continents, and its human casualties in the world are estimated to be around 55,000 people every year. On the other hand, about 99% of these deaths occur in developing or underdeveloped countries, and more than 99% occur as a result of rabid dog bites. About 56% of human deaths due to rabies occur in Asia and 44% in Africa, and losses in other continents are not significant. In the continent of Africa and Asia, the annual loss of rabies to livestock is estimated to be around 12.3 million animals. Most of the damages caused by the disease in the United States include the costs of prevention in people bitten by animals, and almost all of it is related to bites by wild animals and prevention in people at risk.  These costs are about 300 million dollars annually. In Central and South America, in 1985, the annual loss of cattle and calves due to rabies was estimated at 100,000 and the annual damages were estimated at 30 million dollars. In the world, more than one billion dollars are spent annually to prevent rabies. In Iran, human deaths from rabies are about 2 to 10 people per year, but livestock losses and losses fluctuate a lot and may include 200 cows and calves.

Domestic and wild carnivorous animals and bats are the reservoir of the rabies virus, which can transmit the disease to other mammals, including humans and domestic animals. Humans are usually the final host for the virus, and transmission from humans to humans and other animals is rare. In Europe, the red fox is considered the most important reservoir of the disease. Therefore, in France, to control the disease in red foxes from 1986 to 1995. About 261 million dollars have been spent, which is mostly related to the prescription of oral vaccine for this animal.

Dogs and other carnivorous animals that are infected with the disease excrete the disease virus along with salivary secretions, and in most cases, this virus enters the human body and other domestic animals through the bite of a rabid animal. The rabies virus does not enter the blood of the sick animal, so there is no viremia in this disease. However, the virus is excreted alternately with saliva and urine and is found in the cerebrospinal fluid and in some other tissues such as the central nervous system, salivary glands and muscles. Therefore, to control the disease, it is better to burn or bury the carcasses as soon as possible to reduce the contamination of the environment with the virus. Sometimes in North America, disease transmission is caused by the bites of blood-sucking bats.

The basis of rabies prevention and control is based on disease control in animals, which can be followed in three main parts: 1. Wildlife disease control 2. Disease control in the population of dogs without owners 3. Disease control in the owner's dog population 1- Disease control in wildlife The importance of wildlife in the spread of rabies in Iran is not very clear, although many cases of attacks by wolves, jackals and rabid foxes on animals and humans have been reported. To control the disease in these animals, there is an edible vaccine available in the market, which is placed inside the prey such as a chicken's head and spread on the path or place of gathering of wild animals. 2 - Disease control in the population of dogs without owners Dogs without owners are one of the most important reasons for biting people in our country. Therefore, to control the disease, these dogs must be vaccinated or controlled or exterminated in some way. In practice, it has been seen that the extermination of dogs is not very effective considering their reproductive characteristics, which usually give birth twice a year and give birth to several puppies each time. Because they increase their population again only in a short period of time. On the other hand, extermination is often done with the use of firearms, and due to the howls of animals when they die, people usually do not show much desire to exterminate them. In addition, it is difficult to catch dogs and destroy them after injecting the painkiller. Therefore, in recent years, it has been suggested to catch dogs and release them after sterilization and vaccination. In this case, breeding of dogs is prevented biologically. Following this method in some places like some states of India has had a very favorable result. Another method has been used to vaccinate stray dogs in Nepal, which can be used in other places after study. Officials of the World Animal Health Organization in the study of rabies in Nepal found that many stray dogs are not owned but are related to people and they can control these dogs. Therefore, in the implementation of the vaccination program, people were asked to restrain these dogs for vaccination, and this plan was successfully carried out. 3- Disease control in the owner's dog population Control of the disease in the owner's dog population is usually done by injecting a vaccine and marking them using a collar. Also, sick dogs and suspicious dogs are destroyed or quarantined. To control the disease in the owner's dog population, at least 70% of them should be vaccinated.

If you are bitten by animals, to prevent the disease: 1- Wash the bitten place quickly with soap and water, and if soap is not available, wash well with water. 2- Avoid dressing the wound. This simple action can prevent you from contracting rabies in many cases. However, to be sure, you should go to the health center as soon as possible so that you can be injected with anti-rabies vaccine and serum. Note that if the disease in humans is not prevented in time and the disease appears, the human usually dies within one to five days after the onset of clinical symptoms. In any case, rabies is incurable and eventually causes the death of the patient.

If the halal meat trap is bitten by a rabid animal, it can be slaughtered for up to 48 hours and the meat can be used after separating the bite site. But after this period, due to the fact that the virus grows and multiplies in the animal's body, these animals cannot be slaughtered and their meat cannot be consumed, and they must be exterminated. Of course, these animals can be quarantined for about 6 months, and if the disease does not appear, they can be declared free of the disease by taking special measures and removed from the quarantine. But during this period even the milk of those animals should not be used and usually due to the high costs, quarantine of these animals is not possible and extermination is preferred.