Rabies: Symptoms, Causes, Treatment

What are the symptoms of rabies?

Rabies is a viral infection that affects the central nervous system and can be fatal if not treated promptly. The symptoms of rabies typically progress through several stages:

1. Prodromal Stage (Early Symptoms)

• Fever: Usually mild but can be present.
• Headache: Persistent and can be severe.
• Fatigue and Weakness: Generalized malaise and discomfort.
• Pain or Paresthesia at the Bite Site: Tingling, itching, or discomfort at the site of the animal bite, even if it has healed.
• Nausea and Vomiting: These gastrointestinal symptoms are common.

2. Acute Neurological Stage

• Agitation and Anxiety: Severe restlessness, confusion, or agitation.
• Hydrophobia: Fear of water, where even the thought or sight of water can cause painful spasms in the throat.
• Aerophobia: Fear of drafts of air or wind, which can trigger throat spasms.
• Hallucinations: Visual or auditory hallucinations may occur.
• Hyperactivity: Extreme and uncontrollable movements or behaviors.
• Difficulty Swallowing: This can lead to drooling or foaming at the mouth.
• Muscle Spasms and Paralysis: Gradual paralysis, often beginning in the lower limbs.

3. Coma and Death

• Paralytic Stage: Progressive paralysis leading to respiratory failure.
• Coma: The patient may slip into a coma, typically occurring within a few days of severe symptoms.
• Death: Death usually occurs from cardiac arrest or respiratory failure.

What are the causes of rabies?

Rabies is caused by the rabies virus, which is a member of the Lyssavirus genus. The virus primarily affects mammals and is usually transmitted through the saliva of an infected animal. Here are the main causes and modes of transmission:

1. Animal Bites

• Dog Bites: The most common cause of rabies in humans, especially in regions where rabies is prevalent in stray or unvaccinated dogs.
• Bat Bites: In many countries, especially in the Americas, bats are a significant source of rabies transmission.
• Other Mammals: Raccoons, skunks, foxes, and coyotes are also common carriers of rabies and can transmit the virus through bites.

2. Non-Bite Exposure

• Scratches: Although less common, scratches from an infected animal can transmit rabies if the animal’s saliva contacts the wound.
• Open Wounds or Mucous Membranes: The virus can enter through open cuts, wounds, or mucous membranes (such as the eyes, nose, or mouth) if they come into contact with the saliva or brain tissue of an infected animal.

3. Rare Transmission Modes

• Inhalation: In very rare cases, rabies has been transmitted through inhaling aerosolized virus particles in bat caves or laboratories.
• Organ Transplants: Transmission through organ transplants from an infected donor has been reported, although this is extremely rare.
• Human-to-Human Transmission: Direct human-to-human transmission through bites is extremely rare, though it has occurred in isolated cases, particularly through organ or tissue transplants.

Reservoirs of the Virus

• Wildlife: In the wild, rabies is maintained in populations of bats, raccoons, skunks, foxes, and other carnivores.
• Domestic Animals: Unvaccinated domestic dogs and cats can become infected and transmit rabies to humans.

Rabies is nearly always fatal once symptoms appear, but it can be prevented if post-exposure prophylaxis (PEP) is administered promptly after exposure. This involves a series of rabies vaccinations and, in some cases, rabies immune globulin (RIG).

What is the treatment for rabies?

Treatment for rabies depends on whether exposure to the virus has occurred or if the disease symptoms have already developed.

1. Post-Exposure Prophylaxis (PEP)

PEP is the main treatment approach for rabies exposure before the onset of symptoms. It is highly effective if administered promptly.

• Immediate Wound Care:
• Thoroughly wash the wound with soap and water for at least 15 minutes to reduce the amount of virus.
• Disinfect the wound with an antiseptic, such as iodine or alcohol.
• Rabies Vaccination:
• Series of Rabies Vaccines: Administer a series of rabies vaccines (four doses typically) over a period of 14 days. The vaccine stimulates the immune system to fight the virus.
• Day 0 (the day of the first vaccine), Day 3, Day 7, and Day 14 are the usual schedule days for these injections.
• Rabies Immune Globulin (RIG):
• Administer RIG only if the person has not been previously vaccinated against rabies. This is a dose of antibodies that provides immediate, short-term protection while the body responds to the rabies vaccine.
• The RIG is injected directly into the wound and, if necessary, into the muscle near the bite site.

2. Post-Symptom Treatment

Once rabies symptoms appear, the disease is almost universally fatal. However, experimental treatments have been attempted:

• Milwaukee Protocol:
• This is a controversial and experimental treatment method that involves placing the patient in a medically induced coma to protect the brain while the body attempts to fight off the virus. The success rate is extremely low, and very few patients have survived using this method.

3. Supportive Care

If a person develops symptoms of rabies, treatment focuses on comfort and supportive care, as there is no cure:

• Pain Management: Pain relief and sedation may be provided to manage symptoms like seizures, agitation, and muscle spasms.
• Respiratory Support: Mechanical ventilation may be necessary if the patient develops respiratory failure.
• Fluids and Nutritional Support: Intravenous fluids and nutritional support may be provided.

Prevention

• Vaccination:
• Pre-Exposure Vaccination: For people at high risk, such as veterinarians, animal handlers, or travelers to areas where rabies is common, pre-exposure vaccination is recommended.
• Animal Vaccination: Regular vaccination of pets and domestic animals is crucial in preventing the spread of rabies.

Prompt and appropriate post-exposure treatment is the key to preventing rabies. Once clinical symptoms have appeared, the chances of survival are extremely low, making prevention through PEP critical.