Rabies, a zoonotic disease that affects the central nervous system, is progressive and fatal if not treated promptly. Its characteristic symptoms, which vary depending on the stage, culminate in brain and spinal cord inflammation, which inevitably leads to death.
Prevention through post-exposure vaccination is crucial, as once the rabies virus spreads, the outcome is fatal.
The disease is a global public health concern. According to the World Health Organization (WHO), despite the availability of effective vaccines, rabies still causes the deaths of approximately 59,000 people each year, primarily in Asia and Africa.
Its transmission occurs through contact with the saliva of infected animals, commonly through a bite or scratch.
The stages of rabies: from incubation to paralysis
The course of rabies disease is divided into several well-defined clinical stages, each with its own set of symptoms.
1. Incubation period
This initial phase is asymptomatic and can last from one week to several months, although the average is one to three months.
During this time, the virus moves from the point of entry (the bite wound) to the central nervous system. It is during this period that post-exposure prophylaxis with the vaccine is completely effective in preventing the development of the disease.
2. Prodromal Stage
Lasting two to ten days, this phase marks the onset of nonspecific symptoms that are often confused with those of the common flu. The most common initial signs include:
- Fever with chills.
- Tingling, itching, or altered sensitivity at the wound site.
- Joint and muscle pain.
- Generalized fatigue.
3. Stage of the disease
Once the virus reaches the brain, the disease manifests in its most aggressive form. This phase, which lasts between two and seven days, is characterized by brain inflammation (encephalitis) and occurs in two main forms:
Furious (or violent) rage: It accounts for about 70% of cases. It is characterized by symptoms of hyperactivity, anxiety, excitement, and delusions. Patients may experience violent attacks and muscle spasms. Laryngeal spasms are particularly noticeable, impairing swallowing and causing hydrophobia (fear of water) and aerophobia (fear of drafts). Seizures may also occur.
Paralytic (or dumb) rabies: It affects the remaining 30% of patients. This variant, although less dramatic, is equally lethal. It is characterized by progressive muscle paralysis that begins at the site of the bite and spreads throughout the body, as well as loss of sensation. Its course is longer, but the outcome is the same.
4. Coma and Death
Regardless of the type of rabies, the disease culminates in a coma lasting one to ten days. Fatalities result from cardiorespiratory failure or, in some cases, secondary infections.
