Rabies: Causes, Symptoms, Transmission, Treatment and Prevention
Rabies is a viral, zoonotic disease. It is most often transmitted through the bite of a rabid animal. In up to 99% of cases, domestic dogs are responsible for the transmission of the rabies virus to humans. However, rabies can affect both domestic and wild animals.
The rabies virus infects the central nervous system of mammals, causing brain disorders. Most of the annual rabies cases reported to the Centers for Disease Control and Prevention occur in wild animals, such as bats, raccoons, skunks, and foxes.
Once clinical symptoms appear, rabies is virtually 100% fatal. Although it is a deadly viral disease, it can be prevented through vaccination.
The disease is present primarily among poor and vulnerable populations living in remote rural locations. Approximately 80% of human cases occur in rural areas.
Mode of transmission
The rabies virus is transmitted through direct contact (via broken skin or the mucous membranes of the eyes, nose, or mouth) with the saliva or tissue of an infected animal. People usually get infected following the bite of a rabid animal. It is also possible – though rare – for humans to contract rabies from exposures other than bites, such as scratches, abrasions, or open wounds that are exposed to saliva or other potentially infectious materials.
Other types of contact, such as petting a rabid animal or contact with the blood, urine, or feces of a rabid animal, are not associated with the risk of infection.
Transmission of rabies via transplants has been recorded, but it is very rare.
As an RNA virus from the Rhabdoviridae family, once the virus is contracted, it can spread in the body in two ways. The rabies virus can enter the peripheral nervous system directly and travel to the brain or replicate in muscle tissue, where it is sheltered from the host's immune system. From there, it enters the nervous system through the neuromuscular junctions.
Symptoms
Symptoms of rabies begin about 3 weeks after infection. The most common symptoms of rabies consist of pain at the site of inoculation, anxiety, weakness, discomfort, hydrophobia (fear of water), aerophobia (fear of drafts or air movements), and/or delirium. The infected person often experiences episodes of fever, tremors, painful spasms, and/or excessive salivation.
As the virus continues to attack the nervous system, two different types of the disease can develop: furious rabies and paralytic rabies.
People who develop furious rabies will be hyperactive and excitable and may exhibit erratic behavior. Other symptoms include:
- insomnia
- anxiety
- agitation
- confusion
- hallucinations
- excessive salivation or foaming at the mouth
- difficulty swallowing
- fear of water
Paralytic rabies takes longer to set in. Infected people become paralyzed slowly, eventually slipping into a coma and dying.
Diagnosis
There is no test to detect early stages of rabies infection. When a person is bitten by an animal that might be infected, doctors will immediately start prophylactic treatment by administering a preventive rabies vaccine injection to stop the infection before symptoms occur.
After symptoms appear, a doctor may recommend blood, tissue, or saliva tests to confirm the virus infection.
Treatment
In case of a bite, it is recommended to clean the area with soap and water. Contact a doctor to determine if you need rabies treatment known as post-exposure prophylaxis (PEP), which consists of a dose of immunoglobulin and four doses of rabies vaccine administered over a 14-day period.
Prevention
The best way to prevent it is by avoiding wild animals, including injured ones. If you find an injured animal, do not touch it; instead, contact local authorities for assistance.
Since pets can contract rabies from wild animals and then transmit it to humans, preventing rabies in pets is also an important step. The disease can be prevented by vaccinating pets. There are several rabies vaccines approved for dogs, cats, horses, and domestic ferrets. All dogs and cats between 12 and 16 weeks old should be vaccinated by a veterinarian.
If you come into contact with a rabid animal, human rabies can be prevented with prompt and appropriate medical care. See a doctor before symptoms appear.
Vaccination is recommended for people who are in constant contact with animals, whether wild or domestic.
References
https://www.who.int/news-room/fact-sheets/detail/rabies
https://www.healthline.com/health/rabies
https://kidshealth.org/en/parents/rabies.html
https://vcahospitals.com/know-your-pet/rabies-in-dogs
https://www.cdc.gov/rabies/transmission/index.html
https://www.medicalnewstoday.com/articles/181980#what-is-rabies
https://www.medlife.ro/glosar-medical/afectiuni-medicale/rabie-turbare-cauze-simptome-tratament
https://www.alphega-farmacie.ro/articole/afectiuni/rabia-boala-uitata
https://www.catena.ro/dictionar/rabie
https://doc.ro/sanatate/rabia-boala-fatala-care-poate-fi-prevenita
