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The 5 Worst Diseases in History


K S Lane is a student of pharmacology and has a deep and passionate interest in all kinds of ailments and medications.

Diseases are often horrifying things. They cause terrible symptoms, physical disfigurement and often death. But they can also be fascinating, which is probably why you clicked on this article. To feed your macabre curiosity I’ve listed below five of the worst diseases known to mankind. Be warned: some of them are the stuff of nightmares.

This article lists the 5 worst diseases of all time

This article lists the 5 worst diseases of all time

1. The Most Infectious Disease: Measles

Measles is a condition that most people in first-world counties pay little attention to. Vaccines for measles are widely available and almost completely effective. In the days before the development of the measles vaccine in 1963, however, the disease struck true fear into peoples' hearts. Measles is so contagious that if one person has it nine of ten people closest to that person who are not immune will also become infected. Even in the modern world 430 children die from measles and its complications every single day. The majority of these children are infants who are too young to be vaccinated, have a severe allergy to one of the components in the shot or have parents that think vaccines are mind control mechanisms made by aliens on Pluto.

Symptoms of measles include a red, spotted rash that spreads across the skin. Yikes.

Symptoms of measles include a red, spotted rash that spreads across the skin. Yikes.

2. The Most Painful Disease: Cluster Headache

Cluster Headache is one of the most painful conditions known to mankind. The headaches typically last from 15 minutes to three hours and are characterised by intense, unilateral (one sided) pain around one eye. About 1 in every 1000 people experience them and sufferers have described the pain as "feeling like my eye is going to explode." On sufferer reported that she doesn't keep guns in her house for fear that she'll be driven to suicide when the headaches strike. In summation, it’s a really terrible condition and you definitely don’t want it.

"It feels like a hot poker being thrust through my eye socket."

— A cluster headache sufferer on the pain that he experiences

3. The Most Deadly Disease: Rabies

New, exotic diseases like Ebola and the Zika virus are often thought to be the most deadly of diseases, but in actuality they don’t hold a candle to the cold efficiency of a disease that’s been around since the 1500s; Rabies. An effective vaccine for the condition was developed in 1885 by Louis Pasteur, but before the days of the vaccine rabies was a death sentence. There are only 8 to 10 recorded cases of people surviving rabies after infection, and when you consider that there have been hundreds of thousands of cases worldwide you can start to understand the significance of that. The survival chance is virtually zero. Let’s all take a moment to appreciate good old Louis Pasteur; his expert science-ing saved a lot of people from a pretty horrible fate.

Stray dogs can be particularly susceptible to rabies, as fighting with other infected animals can pass the disease on.

Stray dogs can be particularly susceptible to rabies, as fighting with other infected animals can pass the disease on.

4. The Most Widespread Disease: Hepatitis-B

Hepatitis-B is estimated to affect two billion people worldwide, which is approximately one quarter of the population. It’s a liver infection and can cause long term problems like cirrhosis, jaundice, nausea and liver cancer. Thankfully, not all strains of hepatitis-B are lethal, otherwise the world would be two billion people fewer. The main concern is for the 350 million people who have the chronic form of the illness, which can be fatal.

5. Most Gruesome: Leprosy

Given that the majority of diseases are fairly horrific, naming one as the most gruesome is difficult. However, the spine-chilling physical symptoms of leprosy make the disease a good candidate for such a superlative. Suffers of leprosy, also called Hansen’s disease, initially experience ulcers, skin lesions and eye damage. In the later stages of the condition larger ulcerations, loss of fingers and toes and facial disfigurement may develop. Poor Hansen. Imagine having your name associated with such a horrible disease.

Leprosy causes severe facial and bodily disfigurement

Leprosy causes severe facial and bodily disfigurement

Honourable Mentions

  • Smallpox: smallpox has wracked up the highest death toll of any disease, claiming 300 million victims. The first vaccine was developed by Edward Jenner in 1796. Again, let’s take a moment to thank the scientists for their general braininess.
  • Chronic diarrhoea: fairly self-explanatory. It’s responsible for killing around 525,000 children every year.
  • Epidermodysplasia Verruciformis: along with having a very hard to pronounce name, this causes the growth of tree-bark like warts all over the body. The warts can be removed through surgery, but are highly aggressive and grow back over time.
  • Bubonic plague: this sucker managed to wipe out 60 percent of Europe in less than a decade and causes egg-sized, painful lumps to appear on the body. Not nice.
  • Necrotising fasciitis: flesh eating bacteria chomp their way through the body’s soft tissue after infecting a wound. Very not nice. (Don’t google pictures of this one. You’ve been warned).

New diseases to come?

And there you have it, folks; five of the most infectious, painful, deadly, widespread and gruesome disorders and diseases to date. If these aren’t horrible enough for you then fear not, because new viruses and diseases are mutating all the time. In 50 years we may have a new disease that’s even worse than some of these to add to the list! Isn’t that an exciting prospect?

Were you paying attention? Take this quiz to test your knowledge!

For each question, choose the best answer. The answer key is below.

  1. The measles vaccine was developed in which year?
    • 1963
    • 1965
    • 1960
    • 1962
  2. How many children die of measles each day?
    • 600
    • 400
    • 430
    • 370
  3. Cluster headaches typically last...?
    • For 4 hours
    • From 5 to 10 minutes
    • From 3 hours to a day
    • From 15 minutes to 3 hours
  4. How may recorded cases are there of people suriving rabies?
    • None
    • 8 to 10
    • 200 to 300
    • 6 to 15
  5. Hepatitis B attacks which organ?
    • Heart
    • Liver
    • Stomach
    • Brain
  6. How many people are affected by Hepatitis B worldwide?
    • 900 million
    • 300 million
    • 5 billion
    • 2 billion
  7. Leprosy is also known as?
    • Johnson's disease
    • Korsakoff syndrome
    • Hansen's disease
    • Sanderson's disorder

Answer Key

  1. 1963
  2. 430
  3. From 15 minutes to 3 hours
  4. 8 to 10
  5. Liver
  6. 2 billion
  7. Hansen's disease

Interpreting Your Score

If you got between 0 and 2 correct answers: Hmmm, I think you need to revise a little.

If you got between 3 and 4 correct answers: A solid effort; you're on your way to becoming a diseases expert, but you need a little more revision.

If you got 5 correct answers: Not bad at all! Keep practicing and you're sure to become a disease-master.

If you got 6 correct answers: Great work! Next time, aim for a hundred! I know you can do it!

If you got 7 correct answers: You're a diseases master! Well done!

Sources and further reading:

  • http://conditions.health.qld.gov.au/HealthCondition/condition/14/217/91/Measle
  • https://www.healthline.com/health/top-10-deadliest-diseases
  • https://list25.com/25-deadliest-diseases-in-human-history/
  • https://www.cdc.gov/rabies/index.html
  • https://www.hepatitisaustralia.com/hepatitis-b-facts/about-hep-b
  • https://www.migrainetrust.org/about-migraine/types-of-migraine/other-headache-disorders/cluster-headache/
  • https://www.medicinenet.com/leprosy/article.htm

© 2017 K S Lane

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