Rabies: Causes, Symptoms, Diagnosis, Treatment, and Prevention
What is rabies and how does it affect humans and animals?
A deadly viral disease, Rabies affects both humans and animals' brains and nervous systems. Usually transmitted by bites or scratches, rabies is spread by saliva and brain tissue from infected animals. There are many mammals that can contract rabies, but it is more common in dogs, bats, raccoons, foxes, and coyotes. Rabies is found on every continent except Antarctica, but it is more prevalent in Asia and Africa, where most human fatalities occur.
What are the symptoms of rabies?
There are four stages to rabies: incubation, prodromal, acute neurological, and coma. As a result of exposure and the severity of the wound, the incubation period can vary from a few days to several years, depending on the amount of virus, the location and severity of the wound, and the immune system of the individual or animal. Symptoms of the prodromal phase include fever, headache, anxiety, sore throat, cough, and tingling at the bite site. A prodromal stage lasts between two and ten days. Rabies is characterized by the acute neurological stage, which involves neurological symptoms such as aggression, confusion, hallucinations, hydrophobia (fear of water), hypersalivation (excessive drooling), difficulty swallowing, convulsions, paralysis, and respiratory distress. There are two to seven days of acute neurological symptoms. A coma can last from a few hours to a few days after rabies has reached its final phase, resulting in death from cardiac or respiratory failure.
How is rabies diagnosed and treated?
For diagnosing rabies, saliva, blood, cerebrospinal fluid, or brain tissue of a suspected person or animal is tested. Fluorescent antibody tests are the most reliable way to detect rabies antigens in brain tissue samples. However, this test can only be performed after death or euthanasia of the animal, or in rare cases, a biopsy of the person. Thus, rabies diagnosis is often based on clinical signs and exposure history.
A series of injections of human rabies immunoglobulin (HRIG) and rabies vaccine is used to treat rabies as part of post-exposure prophylaxis (PEP). A rabies vaccine is a preparation of weakened or killed viruses that stimulate the immune system to produce antibodies, which neutralizes the virus and prevents it from spreading. HRIG is a preparation of antibodies that neutralize the virus and prevent it from spreading. It is important to administer PEP as soon as possible after exposure, preferably within 24 hours of exposure, and before symptoms develop. If given correctly and timely, PEP is highly effective in preventing rabies. Rabies, however, cannot be treated effectively once symptoms appear, and it almost always leads to death.
How can rabies be prevented?
By avoiding wild and stray animals, especially those that act abnormally or aggressively, you can prevent rabies. Immediately seek medical attention if you are bitten or scratched by an animal, as well as washing the wound thoroughly with soap and water. Depending on the type, location, and severity of the exposure, as well as the animal's vaccination status, PEP should be administered according to the recommendations of the health authorities. If the animal is rabies-free by testing or observation, PEP is not required.
Vaccinating pets and domestic animals against rabies, and keeping them away from wildlife, is another important measure to prevent rabies. In addition to protecting animals from getting and transmitting rabies, vaccination reduces the need for PEP in case of exposure. In many countries, vaccination programs for dogs have succeeded in eliminating canine rabies, and have also reduced human rabies cases.
It is also recommended that travelers traveling to rabies-endemic or epidemic areas receive pre-exposure prophylaxis (PrEP), which involves receiving three doses of the vaccine prior to their trip. In case of exposure to rabies, PrEP can provide partial protection, and can simplify the PEP regimen. However, PrEP does not eliminate the need for PEP, and travelers should still avoid contact with animals and seek medical attention if exposed.
Summary
An infected animal's saliva or brain tissue transmits the disease, usually through a bite or scratch. Rabies is a deadly disease that affects both humans and animals. Pets and domestic animals can be vaccinated against rabies by avoiding contact with wild and stray animals, washing wounds with soap and water, getting PEP after exposure, and washing wounds with soap and water. PrEP is also effective in preventing rabies when it is taken before traveling to areas where rabies is prevalent. Rabies can be treated with PEP if given as soon as possible following exposure, but once symptoms appear, there is no cure.
