What is rabies? How did it originate?
Rabies is a preventable but potentially fatal viral disease that attacks the central nervous system. It was first recorded around 4,000 years ago and is endemic in over 150 countries worldwide. The virus can affect mammals of all kinds. The first human vaccination against the disease was given in 1885, and despite being highly preventable through vaccination, rabies currently kills approximately 59,000 people every year.
Once symptoms of rabies appear, the disease almost always results in death for the person displaying these symptoms. Only 14 people around the world have survived being infected after showing symptoms of rabies as of the year 2016.
Cases of human rabies in the United States are rare, with only 1 to 3 cases reported annually. Twenty-five cases of human rabies have been reported in the United states in the past decade (2009-2018). Seven of these infections were acquired outside of the U.S. and its territories.
What are the symptoms of rabies?
There are two types of rabies, furious rabies and paralytic rabies. In the early stages, both kinds present symptoms similar to many other diseases, including a high fever, headache, and general discomfort and fatigue.
As the disease develops, furious rabies causes muscle spasms in the diaphragm and throat, which leads to a fear of water due to an inability to swallow, while overproduction of saliva causes foaming at the mouth. Infected persons feel anxiety and often display violent, confused or hyperactive behaviour, and experience hallucinations, paralysis, coma and then death.
In paralytic rabies, also known as dumb rabies, the primary symptom is muscle weakness, which leads to paralysis, starting from the infection site and spreading to other parts of the body with fatal results.
Symptoms can appear within hours of infection, or up to 12 weeks later. For this reason, it’s important to seek medical advice after a bite or scratch in a high risk area, even if you feel fine.
How is rabies transmitted?
Rabies is spread through the saliva of an infected animal via a bite or scratch. Any mammal can carry the virus, but the most common carriers are dogs, bats, foxes, raccoons, jackals, mongooses and cats.
99% of human deaths from rabies worldwide are a result of infection by a rabid dog.
What is the transmission seasonality?
Rabies rates are not generally seasonal but there is some evidence that infection rates from bats are lower during colder months due to hibernation patterns.
What should you do if you are bitten or scratched by an animal that you think might be rabid?
If you have been bitten or scratched by an animal that you suspect may be a carried of rabies, the the CDC’s recommendations are as follows:
- Thoroughly clean the bite or scratch with soap and water and povidone iodine or other substances with virucidal activity, if you have access to them
- Visit a doctor as soon as possible after you have been bitten or scratched, and at the very least, on the same day of the incident, as the doctor will be able to provide you with postexposure prohphylaxis (PEP) – this is a treatment that is almost 100% effective in preventing the onset of rabies
- Ensure that the doctor provides you with the necessary treatment – rabies immunoglobin may be injected into the site of the wound after the wound is cleaned thoroughly, followed by a course of rabies injections
- For those who have not been vaccinated against rabies previously, a series of 4 doses of the rabies vaccine will be administered on day 0 (the day of the bite or scratch), day 3, day 7 and day 14. For those who have already received the full course of rabies vaccine prior to exposure to rabies, only 2 doses are necessary, administered on days 0 and 3.
- Adhere to the vaccine schedule as strictly as possible
If you are going to be travelling to areas where there is a risk of rabies or where you are going to be in contact with animals, it is best to receive a course of the rabies vaccine prior to your trip.
What is a rabies certificate?
A rabies certificate is issued to prove an animal or human has been vaccinated and should be carried when travelling to different countries where they require it. Examples can be found on the CDC website.
Is rabies curable?
Once symptoms appear, rabies is usually always fatal. However, if treatment begins before symptoms appear, it is very effective in curing the disease.
If you are bitten or scratched in a high risk area of the world, immediately wash the area with soap and running water for several minutes, disinfect with an iodine-based disinfectant or alcohol, and dress the wound. Seek professional medical help as soon as possible, and explain that you have been scratched or bitten.
Medical treatment should begin within a few hours of contact with a rabid animal, and involves further jabs of the rabies vaccine and possibly immunoglobulin, which helps your body fight the virus.
How to prevent rabies?
The best way to prevent rabies is by vaccination.
When travelling to a place where there is a risk of rabies, the CDC recommends you avoid all contact with wild or domestic animals, alive or dead, as the signs of infection are not always obvious.
It is important to explain the dangers of rabies to any children you are travelling with, and ensure they tell you if an animal scratches, bites or licks them. If they do come into contact with any animal, check carefully for any wounds so action can be taken against the disease.
Even if you have had the rabies vaccination, you should seek medical treatment if you come into contact with an animal that may have rabies.
How long before a trip do you have to get rabies vaccine?
Vaccination against rabies requires a course of treatment which takes up to four weeks to complete. You should therefore start the course at least one month before you leave on your trip.
Who should get the rabies vaccine?
If you are planning to visit a place where rabies is common, you are advised to get vaccinated.
This is especially important if you plan to stay for more than a month, if access to medical treatment is limited or if you plan to do any high risk activities, for example cycling, running or exploring the wilderness.
If you are pregnant you are advised to get vaccinated if there is a high risk you could be exposed to rabies and there is a lack of access to medical care.
Some people are advised to get vaccinated due to exposure to the virus through their work. This includes people handling bats or imported animals in quarantine centers, and laboratory workers who handle samples of the rabies virus.
Who should not get the rabies vaccine?
The CDC does not recommend the rabies vaccine for people who have previously experienced an allergic reaction to the rabies vaccine or any component of the vaccine.
If you have a weakened immune system because of HIV/AIDS, cancer or other diseases that affect the immune system, are taking medications that affect your immune system, have cancer, or are going through cancer treatment with radiation or drugs, the vaccination is not recommended.
Should any of the above apply to you, contact your doctor for further advice on whether or not you should have the vaccination.
If you have come into contact with an animal with rabies, you will need to get vaccinated anyway as part of your post-exposure treatment.
What is the minimum age requirement for rabies vaccine?
According to the World Health Organization (WHO), the rabies vaccine can be given to people of all ages, including infants under 1 year.
What is the effectiveness of the rabies vaccine?
Both the WHO and CDC rate the rabies vaccine as safe and effective in preventing rabies.
Post-exposure treatment is nearly 100% effective if it’s started before any symptoms of rabies appear.
What are the side effects of the rabies vaccine?
Mild side effects usually last a few days, and include redness, pain, swelling and itchiness at the vaccination site, headaches, stomach upset, aching muscles and dizziness.
In rarer cases, you may experience joint pain, fever and hives on the skin. Serious side effects are extremely rare.
How many jabs are needed?
You need at least three doses of the vaccine to be protected. The second jab is given a week after the first, and the third is administered either 21 or 28 days after the first jab.
A person who is exposed and has never been vaccinated against rabies should get 4 doses of rabies vaccine – one dose right away, and additional doses on the 3rd, 7th, and 14th days. They should also get another shot called Rabies Immune Globulin at the same time as the first dose.
A person who has been previously vaccinated should get 2 doses of rabies vaccine – one right away and another on the 3rd day. Rabies Immune Globulin is not needed.
How long does it last for?
You are advised to get a booster vaccine to extend protection one year after initial vaccination, if you plan to travel to a high risk area again.
People whose jobs expose them to a high risk of catching rabies should get a booster jab every six months to two years.
Your doctor can advise you on the best course of action for ongoing protection.
When and where was the last outbreak of rabies?
India has the highest amount of deaths from rabies, around 20,000 a year. Thailand experienced an outbreak of rabies in 2018, attributed to the 10 million stray dogs in the country.
