by Aejaz Iqbal
If someone is bitten or scratched by an animal that might have rabies, or if infected saliva touches an open wound, the first step is to wash the injury for fifteen minutes with soapy water, povidone iodine, or detergent. This reduces the viral load. Medical attention must then be sought without delay.
Rabies is a viral disease that attacks the central nervous system, including the brain. It spreads to humans mainly through the bite or scratch of an infected animal, most often a dog. Once inside the body, the virus moves along the nerves towards the brain, where it causes inflammation. The time before symptoms appear may range from a few days to several months, depending on the location and severity of the bite. Rabies is almost always fatal once symptoms emerge, yet it is fully preventable if treated promptly after exposure. The key is to clean the wound at once and seek medical care without delay.
The first signs of rabies may appear within a few days or take more than a year to surface after a bite. The earliest sensations are tingling, prickling, or itching around the site of the wound. These may be followed by flu-like symptoms, including fever, headache, muscle pain, loss of appetite, nausea, and fatigue.
As the disease advances, neurological symptoms develop. These may include irritability, restlessness, confusion, hallucinations, muscle spasms, seizures, or partial paralysis. Many sufferers become extremely sensitive to light, sound, or touch. Excess saliva may gather in the mouth, while spasms of the throat make swallowing difficult. This creates the well-known image of foaming at the mouth. It also leads to a fear of choking and an intense fear of water, known as hydrophobia.
Doctors often perform several tests, but may not be able to confirm rabies until the disease is advanced. Laboratory results can show antibodies, though these often appear only later in the illness. At times, the virus may be isolated from saliva or through a skin biopsy, yet by the time a diagnosis is certain, it is usually too late for treatment.
For this reason, patients are generally given preventive care immediately after suspected exposure, without waiting for confirmation. If a person develops viral encephalitis after an animal bite, doctors treat them as if they may have rabies.
The incubation period is the time between exposure and the appearance of symptoms. It usually lasts two to three months but can range from one week to a year. The duration depends on where the virus entered the body and how much virus was introduced. A bite closer to the brain tends to bring faster symptoms. Once the signs begin, rabies is almost always fatal. Anyone exposed should seek medical attention at once, without waiting for illness to appear.
Rabies infection is caused by the rabies virus, which spreads through the saliva of infected animals. It is most often transmitted through bites, but in rare cases, it can enter through open wounds or mucous membranes such as the eyes or mouth. An example would be when an infected animal licks an open cut on the skin.
If someone is bitten or scratched by an animal that might have rabies, or if infected saliva touches an open wound, the first step is to wash the injury for fifteen minutes with soapy water, povidone iodine, or detergent. This reduces the viral load. Medical attention must then be sought without delay.
Before symptoms appear, a series of injections can prevent rabies from developing. Since it is often impossible to know whether the animal carried the virus, doctors usually assume it did and begin treatment. Once symptoms have begun, treatment focuses only on comfort and breathing support.
The rabies vaccine is not given routinely. It is reserved for those at high risk, such as laboratory workers, veterinarians, or people frequently in contact with animals. These individuals may receive preventive vaccinations.
Others may receive the vaccine after suspected exposure to the virus, in what is known as post-exposure prophylaxis. The vaccine contains a harmless version of the virus that cannot cause disease but prompts the immune system to produce protective antibodies.
The vaccine is given in the upper arm. For pre-exposure protection, three doses are required over twenty-eight days. For post-exposure protection, people who have not been vaccinated earlier need four doses of the vaccine along with rabies immune globulin. The globulin is administered as soon as possible, close to the wound, to block the virus from entering the nervous system.
(The author is a microbiologist. Ideas are personal.)
