The top 5 deadliest infectious diseases, are:
Names after the Malaysian village it was discovered in, Nipah has an average Case fatality rate (the percentage of people infected who die) of about 50%. It was discovered among pig farmers in 1999 and later in people who had been exposed to fruit previously eaten by bats. The disease can cause serious respiratory problems, hallucinations due to swelling of the brain and in some cases seizures. There are currently no treatments or vaccines for this virus and despite the early beliefs it came only from the animals, it can in fact be easily transmitted by humans.
2. H5N1 – Bird Flu
Mainly found in Asia and Europe, this strain of influenza is most often deadly to birds. However, some really clever scientists one day decided to produce genetically engineered bird flu in order to make it compatible with ferrets. As our immune systems are very similar to ferrets, that means us too.Bird flu has a case fatality rate of about 54% and though there is a vaccine it hasn’t yet been made widely available to the public.
3. Marburg Haemorrhagic fever
The initial 1967 outbreak killed 23% of the scientists who discovered this disease. They were Working on a Polio vaccine at the time and this involved testing on Monkeys imported from Uganda. Surprisingly they found this horrible disease, and they found it by catching it. It caused fevers, vomiting, internal bleeding, diarrhea, and sometimes the eventual shut down of circulatory systems. The official case fatality rate is 23%, but outbreaks keep occurring in Africa and due to condition in these places, the case fatality rate can be increased to about 80%.
One of five species of the dreaded Ebola virus, it is the disease holding winning title for the most outbreaks and deadliest ones. It causes vomiting and fever, failure of blood vessels causing bleeding under the skin and has an average fatality rate of 83%. Scientists today are working ever closer to finding treatments and vaccines for Ebola and new trials are being launched often to help eradicate this deadly disease.
Surprisingly enough, Rabies is actually the deadliest disease in the world in terms of case fatality rates. It has a case fatality rate of about 100% with fewer than 10 known examples of people living through rabies. We have a vaccine to stop us getting it but no treatment once we have begun to show symptoms, this is why it isn’t killing all of us. Once infected, it can takes months for the infection to manifest, so most of the time when someone is bitten by a strange animal they will go and get some shots and not feel a thing.
If you are one of the unfortunate few who develops symptoms though, it’s pretty definite death comes not to far after.