Rabies Disease: Symptoms, Causes, Vaccine, and Treatment

Rabies is a serious disease that can be found worldwide and can lead to death if not treated. Rabies disease, which primarily affects mammals, including humans, is commonly seen. Research has shown that four out of ten children worldwide die from the rabies virus. Increasing awareness of rabies and seeking medical intervention in suspicious cases will reduce the death rate caused by rabies. Although the incidence of rabies has decreased since the 1970s, the rabies virus can still cause serious cases today. Particularly in regions like South Africa and Asia, where there is insufficient information about the rabies virus, the incidence of rabies remains high. Currently, 95% of rabies-related deaths occur in South Africa and Asia. Even for people living in developed cities, the rabies virus can still pose a threat. Therefore, it is important to have detailed information about the disease.

What is Rabies Disease?

Rabies is a zoonotic disease that can be transmitted from animals to humans. Rabies is a viral disease that can affect the nervous systems of mammals and lead to death. The rabies virus is transmitted through the bite of an infected animal, and symptoms can appear within a few weeks or take several months to develop. This means that individuals at risk of contracting rabies should immediately seek medical care. Rabies can be treated if diagnosed early, but if treatment is delayed, it can be fatal.

The rabies virus is an RNA virus and can spread in two different ways in the body. After entering the body, it can enter the peripheral nervous system and travel toward the brain. The peripheral nervous system, also known as the somatic nervous system, facilitates communication between the organs, limbs, and the brain. Once the rabies virus enters the peripheral nervous system, symptoms may appear more quickly. Another method of spread is the multiplication of the virus in safe muscle tissue, followed by spreading to the neuromuscular junctions, or the nerve-muscle junctions, which transmit the signal to the brain. Once the virus enters the nervous system, it causes acute inflammation in the brain. Following the onset of inflammation, coma and death occur in a short period.

Rabies disease appears in two forms. The first type, called furious or encephalitic rabies, accounts for 80% of human rabies cases. In this form, symptoms such as hyperactivity or hydrophobia are observed. The second type, called paralytic or dumb rabies, leads to paralysis in affected individuals.

How is Rabies Transmitted?

One of the most common questions regarding rabies is, "How is rabies transmitted?" Rabies is often feared to be transmitted through street animals, but it is generally transmitted through the bite or scratch of an infected dog. 99% of rabies cases worldwide are due to the bites of infected dogs. Most cases occur as a result of bites or scratches from street dogs. Regular vaccination of dogs can prevent the risk of rabies transmission. However, unvaccinated dogs have a higher risk of transmitting the rabies virus. In addition to dogs, rabies can also be transmitted through bites from animals such as bats, raccoons, jackals, skunks, and foxes. Rarely, rabies virus can also be found in mammalian rodents.

Rabies Disease Symptoms:

Rabies disease exhibits different symptoms depending on the stage of the virus in the host. As the disease progresses through five stages, symptoms become more severe. These stages are as follows:

• Incubation Period: The incubation period is an asymptomatic stage. This process can develop within 1 week to 1 year, depending on how the virus enters the body and the number of viral particles. It is known that the incubation period changes depending on the distance between the bite and the brain. It is important to understand that as symptoms begin to appear, the risk of death from rabies increases.
• Prodromal Period: During the prodromal period, flu-like symptoms are observed. Symptoms include a fever above 38°C, headache, sore throat, cough, nausea, vomiting, fatigue, discomfort at the site of the bite, and signs of anxiety.
• Acute Neurological Period: This is the period when the virus begins affecting the brain and nerves. Various neurological symptoms start to appear. Symptoms include aggression, partial paralysis, uncontrolled muscle twitching, stiffness in neck muscles, foaming at the mouth, difficulty breathing, spasms, photophobia (fear of light), hallucinations, insomnia, frequent nightmares, and persistent erections.
• Coma Stage: After the neurological period, patients enter a coma. This stage typically lasts up to three days, after which the patient dies. During the coma stage, the patient does not respond to treatment.

A common symptom of rabies is hydrophobia (fear of water). This widespread belief is based on the development of hydrophobia in the disease. Patients experience difficulty swallowing due to symptoms in their throat, with intense spasms felt during swallowing, causing discomfort when trying to swallow. Water, which triggers the swallowing reflex, induces anxiety in the patient, leading to the misconception that rabies patients fear water.

Rabies Disease Treatment:

If bitten, scratched, or licked by a stray or unvaccinated animal that is suspected to have rabies, it is crucial to consult a healthcare facility to prevent rabies. Early and accurate diagnosis is life-saving in rabies treatment.

For a person to contract rabies, they must be bitten, scratched, or licked by an infected animal. If the animal is not confirmed to have rabies, the patient undergoes various tests to determine if they have been infected. Laboratory tests are conducted to check for antibody levels, though changes may not be visible during the incubation period. A skin biopsy may be done, but it may not provide a definitive result. It is essential to begin prophylactic treatment as soon as a suspicious event occurs, as waiting too long after the onset of symptoms or diagnosis may be too late for treatment.

When Should the Rabies Vaccine Be Administered?

For individuals at risk of contracting rabies, the question "When should the rabies vaccine be administered?" arises. The rabies vaccine is given immediately after a bite, followed by regular doses. The goal is to help the patient develop antibodies against the rabies virus. The treatment, involving the injection of an inactivated rabies virus, prevents the person from contracting rabies. The vaccine is administered in the upper arm, and the person produces antibodies to protect against potential rabies infection. For rabies protection, the vaccine is given in three doses over 28 days. If exposure or risk of exposure occurs, four doses of the rabies vaccine are administered.

After a suspicious event, taking immediate precautions can be life-saving. It is recommended to wash the bite area with soap and water or an antiseptic such as povidone-iodine within 15 minutes. After washing, the person should seek medical attention at the nearest healthcare facility. If bitten by an animal confirmed to have rabies, rabies immune globulin (RIG) is applied to the wound to prevent infection.

In patients who begin showing symptoms of rabies, the chances of responding to treatment are low. In such cases, doctors focus on alleviating symptoms to comfort the patient. During the prodromal period, patients may require mechanical ventilation.