top of page
  • Instagram
  • TikTok
  • LinkedIn
  • YouTube
  • Facebook
  • Twitter
Search
Daneeya Sheeraz
Jun 19, 20234 min read

Demystifying the Madness of Rabies

Updated: Mar 23


Source: Centers for Disease Control and Prevention (CDC)

✨Outline✨

A Brief Overview

Rabies is a viral disease mostly caught by being bitten by a rabid animal. While any mammal may contract rabies, it is most commonly found in dogs, bats, cats, raccoons, foxes and skunks. Bats are the leading cause of rabies transmission to humans in the United States. However, worldwide, dogs account for 99% of deaths by rabies. Most rabies cases are present in Asia and Africa, alongside tens of thousands of deaths. 40% of deaths due to rabies are in children aged less than 15 years.

Photo by Justin Sullivan/Getty Images

Rabies is contracted when an animal or human is bitten by a rabid animal and the virus in the saliva travels into the wound. The virus then moves to the brain and spinal cord through nerves. This may take 3 to 12 weeks and no symptoms of rabies appear during this time. After reaching the brain, the virus will multiply and cause inflammation of the brain and spinal cord. Then it will move to the salivary glands and infect the saliva. At this point, symptoms start to become apparent. After this stage, most animals will die within a week. After symptoms appear, rabies is 100% fatal or extremely deadly!


Rabies Prevention

Avoiding exposure to animals known for carrying rabies such as unvaccinated dogs and bats is key. Whether an animal does or does not have rabies cannot be assessed just by looking at it, therefore keeping away and avoiding being bitten is the best way to prevent rabies. Vaccinating pets and stray animals against the virus regularly is very important. Pets should also be kept away from stray animals and wildlife that may have the disease.


As children are at highest risk of being bitten by dogs, they should be supervised and taught to behave around animals with care. If a person is bitten, it is preferable that the animal in question be caught and tested.


After being bitten, post exposure prophylaxis (the “action” taken to prevent a disease) should be administered on the day of exposure to humans. This is a dose of human rabies immune globulin and rabies vaccine. The bite wound should also be washed for at least 15 minutes with soap and water. Afterwards, the rabies vaccine is given repeatedly on days 3, 7 and 14 following exposure.


Two doses of pre-exposure prophylaxis can offer rabies protection for up to 3 years. People such as wildlife workers, veterinarians, animal control officers, zoo employees, some laboratory workers and other people regularly in contact with animals that may have rabies are advised to take these doses.


Post and pre exposure prophylaxis is extremely important as after rabies symptoms begin to appear, there is no effectual treatment.

Cases of transmission of rabies by inhalation of infected air droplets or organ transplants of infected organs have been confirmed but are very unusual. Contraction by humans through the bites and saliva of other people is technically possible but has never yet been recorded. The same is true for consumption of milk or raw meat from infected animals.


Signs and Symptoms

The incubation period for this virus is typically 2 to 3 months. However, this may be as little as a week or as long as a year due to several factors. Initial symptoms include tingling sensations, fever, pain and burning of the bite wound.

Rabies occurs as two forms: furious rabies and paralytic rabies. The difference in symptoms is as described below:

  • Furious rabies: hyperactive behaviour, hydrophobia (fear of water), aerophobia (fear of drafts/fresh air), hallucinations and difficulty in coordination. Death happens after symptoms appear from cardiopulmonary arrest.

  • Paralytic rabies: 20% of human rabies cases are paralytic. This form continues for a longer time than furious rabies. Muscles fall prey to paralysis, starting from those near the bite wound. Then the patient develops a coma. Death occurs after this. Paralytic rabies is frequently misdiagnosed.


The Two Protocols for Treatment

A protocol for rabies treatment was developed in 2003 by Rodney Willoughby Jr. It is called the Milwaukee Protocol. A slightly modified but still very similar version of this exists in Brazil as the Recife Protocol. The first case of rabies cured using the Milwaukee Protocol was a 15 year old girl who had received a bat bite to the hand. She was successfully treated in 2004 and survived with only a few complications. Since then, the Milwaukee Protocol has been published as having been used for 38 rabies cases and the Recife Protocol has been used once. Amongst the 38 published cases, 11 people were able to survive.


The protocols are used when the chance to administer post exposure prophylaxis has passed. The patient is put into a medically induced coma and given antiviral drugs alongside ketamine and amantadine. The difference between the two protocols lies primarily in the way sedation is withdrawn. In the Milwaukee Protocol sedation is slowly removed after day 8 and by day 12, the patient receives no sedation. However, in the Recife Protocol to avoid changes to the patient’s immune system (immunomodulation), sedation is removed according to the concentrations of antibodies for the rabies virus present in the cerebral spinal fluid. These protocols were developed to give the patient’s immune system a longer fighting chance while obtaining as little damage to the nervous system as possible by reducing brain activity. However, these protocols need large rabies treatment centres to be able to be carried out, and in places where the majority of rabies cases occur, this sort of infrastructure and resources are not available. Moreover, the Milwaukee Protocol has largely been deemed a failure.


Sources

Comments

bottom of page