Danger from rabies

To date, rabies is still a disease that cannot be cured once it has developed. Every year, around 30,000 - 50,000 people die from rabies worldwide. In Vietnam, in recent years, thanks to the extensive rabies vaccination program and the people's awareness, the proportion of people

Livestock bring easy-to-transmit rabies to humans (Photo: aphis.usda.gov)

Death from rabies gradually diminishes. The number of deaths from rabies in 2000, 2001 and 2003 was 47 people, 60 people and 30 people respectively. However, the number of deaths from rabies in 2004 increased to 82 people. Therefore, people still have to uphold the sense of prevention and vigilance against rabies to continue reducing the mortality rate due to this disease.

* The cause of rabies

Rabies is caused by a virus called rhadovirus. The virus is transmitted to humans when a person is bitten by a rabid animal. The incidence of human disease depends on the incidence of disease in animals. In Vietnam, animals that transmit rabies to the most common are wild dogs; besides it could be cat, bat, monkey .

Wild virus is characterized by a very strong affinity for nerve cells. The virus at the bite only doubles with a small amount in the tissue near the nerve cell and if not killed by the body's immune system, it will begin to enter the nervous system. After the virus enters the nervous system, the immune response produced by the vaccine will no longer effectively kill the virus. Bites at the head, face, and neck are high risk of causing rabies, due to the possibility of virus entering the central nervous system faster.

* Symptoms of rabies

Rabies has an incubation period of about 10 days to 1 year; The average incubation period is 30 to 40 days. During this time the virus invades gradually following the nerve lines to the brain; At that time, symptoms of rabies will begin. The clinical manifestations of people infected with rabies virus are complex but can be divided into 2 main forms:

- Brain rabies : accounts for 70-80% of rabies cases. Patients have manifestations of consciousness disorder, fear of wind, fear of water; Finally, the patient will fall into confusion and death.

- Rabies : paralysis usually starts first in the limb bitten and gradually spreads to all limbs, pharynx, facial muscles and respiratory muscles.

In both cases, death is inevitable within 2-12 days after symptom onset.

Currently, with preventive medicine facilities widely deployed, our country is gradually controlling rabies.In 2004, 610,810 people were vaccinated with rabies.However, there are still about 82 people who develop rabies and die.These deaths are recorded across all regions: North

Pathogenic bacteria (Photo: pathguy.com)

(40 cases), Trung (14 cases), South (22 cases) and Central Highlands (6 cases).Therefore, when bitten by animals, people should not be subjective but must have a sense of vaccination.

One of the most important things is the handling of wounds as soon as the animal is bitten , scratched or even licked on the injured skin to minimize the amount of rabies virus at the place of entry. The following should be done quickly: use soap, or detergent to wash the wound several times under running water; Apply antiseptic such as alcohol 70o solution, alcohol iodine solution at wound. Note not to cover the wound. Immediately go to the nearest preventive health center to get vaccinations and additional instructions. Animal should be monitored for 10 days; If the animal dies during this time, immediately report it to the preventive health officer.

It can be said that the rabies vaccine is a major advance in medicine, helping to repel rabies and save many lives. The rabies vaccine is in fact rabies viruses grown in the laboratory, and then killed (or inactivated). The rabies vaccine is divided into two main groups: Fuenzalida vaccine and cell-based vaccine. The main difference of these two groups of rabies vaccine is the environment used to cultivate the virus.

The rabies vaccine fuenzalida is produced from viral culture in rat brains. Therefore, in the purification process to separate the virus, it is very difficult to remove all unnecessary components such as protein, and myelin of the rat brain. It is these residual components, especially the amount of myelin (a component of the nerve fiber) that is residual, that can cause the nervous system damage of the vaccinated person, such as: encephalitis - meningitis, inflammation Meningitis, meningitis, transverse myelitis . These lesions can occur at a rate of about 1 / 8,000-1 / 27,000 cases of vaccination with fuenzalida vaccine.

Patients with rabies
(Photo: visualsunlimited)

The rabies vaccine inoculated on cells is produced from cell culture of virus.For example, the French Verorab vaccine is produced by cultivating rabies virus on Vero cells.Therefore, there will be no residual myelin and therefore no brain pathology after vaccination.

In recent years, the World Health Organization has advised countries to gradually shift to the use of rabies vaccine on cells, proceeding to stop using fuenzalida vaccine. However, due to economic conditions, there are still two vaccines mentioned above in our country so that people can choose.

In parallel with the vaccination with one of the two vaccines, depending on the location of the bite near the central nervous system, such as the head, face, neck, shoulders, chest, back and regions with many nerves like the tip of the finger hands, toes, genitals or deep wounds, many bites . patients may be given more anti-rabies serum at the site of the wound . The purpose of injecting anti-rabies serum in the wound is to neutralize the remaining viral load after washing the wound, while waiting for the vaccine to produce antibodies for the patient.

To date, rabies is still a disease that cannot be cured once it has developed, and is still causing many deaths in Vietnam. Therefore, people need to pay close attention to the prevention of animal bites; When bitten by animals, it is necessary to immediately go to preventive medicine facilities for timely vaccination and counseling.

Doctor Nguyen Trung Nghia (Director of Preventive Health Center in Can Tho City)