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Health | Diseases & Conditions | Infectious Diseases

Bird flu, malaria, plague and West Nile virus are infectious diseases we've all heard of. Find information on these epidemics and more in this section.

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History of Black Plague

It was said that the cause of the black plague was a particularly sinister alignment of the planets, or a foul wind created by recent earthquakes. Learn more about the history of the black plague and how this disease spread.


5 Ways You Still Can't Get Ebola

 5 Ways You Still Can't Get Ebola

Ebola transmission has been a concern after a major outbreak has killed thousands. See five myths about Ebola transmission to learn how you can't get infected. See more »

How Leper Colonies (Leprosaria) Work

 How Leper Colonies (Leprosaria) Work

Leprosy, or Hansen's disease, was the AIDS of the first millennium. Find out how leper colonies (leprosaria) worked at HowStuffWorks. See more »

10 Diseases That Used to Be Death Sentences

 10 Diseases That Used to Be Death Sentences

Some diseases used to kill millions of people, but not any longer. Learn about 10 diseases that used to be death sentences from HowStuffWorks. See more »

5 Germs You Really Can Get From a Toilet

 5 Germs You Really Can Get From a Toilet

Do you fear the public bathroom? You're not alone. Here are the five likeliest things you could catch from a toilet. See more »

How Ebola Works

 How Ebola Works

Ebola has spread beyond its hub of central Africa and shown up in the far reaches of western Africa. Learn more about Ebola at HowStuffWorks. See more »

5 Rare Parasites Found in the Human Body

 5 Rare Parasites Found in the Human Body

Rare parasites can be creepy. We're willing to bet that you'd go to almost any length to avoid spending time with the five rare parasites. See more »

 What causes cold sores?

Do you know what causes cold sores? Find out what causes cold sores in this article from HowStuffWorks. See more »

 What is the SARS conspiracy theory?

Do you know about the SARS conspiracy theory? Find out about the SARS conspiracy theory in this article from HowStuffWorks. See more »

 How does a virus behave in the body?

In general, people are at their most contagious approximately three days after having been exposed to a virus. You can learn more about how a virus behaves in the body from this article. See more »

 How does the flu spread?

Flu season in North America usually begins in November and runs until March. Learn more about how the flu spreads from this article. See more »