How does rabies manifest after a dog bite in a human? - briefly
Rabies in humans typically manifests with non-specific symptoms such as fever and headache initially. As the disease progresses, it can lead to severe neurological symptoms like hydrophobia (fear of water), photophobia (sensitivity to light), and paralysis.
How does rabies manifest after a dog bite in a human? - in detail
Rabies, caused by the Lyssavirus, is a viral disease that affects the nervous system and can be transmitted through the saliva of infected animals, most commonly dogs. When a person is bitten by an infected dog, the virus enters the body and begins its journey towards the central nervous system (CNS). The incubation period for rabies can vary significantly, ranging from weeks to several months or even years in some cases. However, once symptoms appear, the progression of the disease is rapid and typically fatal.
The initial signs of rabies infection in humans are often non-specific and may include fever, headache, and general malaise. As the virus reaches the brain, more specific neurological symptoms develop. These can be divided into two main stages: the prodromal phase and the acute neurological phase.
The prodromal phase is characterized by a constellation of non-specific symptoms that may include anxiety, confusion, agitation, and changes in behavior. Patients might also experience pain or abnormal sensations at the site of the bite, known as paraesthesia. This phase can last for days to weeks before progressing to the more severe neurological manifestations.
The acute neurological phase is marked by a rapid onset of encephalitis (inflammation of the brain) and other severe symptoms. Patients may exhibit hydrophobia, an intense fear of water that can lead to spasms of the muscles in the throat and larynx when attempting to drink or swallow. Another classic symptom is aerophobia, a fear of drafts or fresh air, which can cause panic attacks and difficulty breathing.
Other neurological symptoms during this phase may include hallucinations, delirium, insomnia, and paralysis. Patients might also develop hypersalivation (excessive saliva production) due to the dysfunction of the autonomic nervous system. The progression of these symptoms is usually rapid and relentless, leading to coma and death within days if left untreated.
It is crucial to note that once clinical signs of rabies appear, treatment options are extremely limited, and the mortality rate approaches 100%. Therefore, prevention through prompt vaccination after a suspected or confirmed dog bite is essential. Post-exposure prophylaxis (PEP) involves the administration of human rabies immunoglobulin (HRIG) and a series of rabies vaccines to prevent the onset of symptoms and save lives.
In conclusion, rabies manifests in humans bitten by infected dogs through a progression of non-specific symptoms followed by severe neurological signs. Recognizing these symptoms early and seeking immediate medical attention can be life-saving, as timely intervention with PEP is the most effective way to prevent this deadly disease.