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Into the Woods ...
Frightening fungi, beastly bacteria and even deadly diseases — it's a wonder anyone heads outdoors anymore. With bugs, parasites and weird bacteria at every turn, what's to stop you from coming down with a rare disease?
But most of the time, people can enjoy the outdoors quite safely without too much fanfare, said Dr. Michelle Barron, an infectious disease specialist at the University of Colorado, Denver.
Knowledge and understanding of diseases can help alleviate people's fears, Barron told Live Science.
So, here's the lowdown on some of the strange diseases you could encounter on your next wilderness jaunt, and some tips on how to avoid them.
GiardiaSlide 2 of 21
The above image shows a Giardia muris protozoan (in blue and yellow) attached to a single intestinal cell, shown in red.
A word to the wise in the wilderness: don't drink unfiltered water — no matter how clean or clear it may appear. You may swallow more than you bargained for; namely, the microscopic parasite Giardia.
The gastrointestinal symptoms that accompany many an-infection are no walk in the woods (think bloating, abdominal pain and watery diarrhea), but they're not so extreme that a person can't live with them, Barron said. Symptoms can last two to six weeks, but anti-parasitic drugs can decrease the amount of time that the symptoms last, according to the Centers for Disease Control and Prevention (CDC).
And while some parasites are only found in certain regions of the country, for Giardia, it doesn't matter where you are in the United States — according the CDC, itcan be found in every region.
Up next, a parasite whose protective shell allows it to survive outside of a warm host.Slide 3 of 21
CryptosporidiosisSlide 4 of 21
Giardia isn't the only parasite lurking in the water — there's also the microscopic parasite Cryptosporidium, which causes cryptosporidiosis (though both the disease and the parasite are referred to as "Crypto").
Unlike Giardia, the tiny protozoan parasite that causes Crypto is protected by an outer shell that allows it to survive for long periods of time without a host, and makes it resistant to certain disinfectants, according to the CDC.
People can become infected when they accidentally swallow water while they're swimming, Barron said. And if Crypto gets into a source of drinking water, entire towns may experience an outbreak, she said.
Barron noted that while the gastrointestinal symptoms are unpleasant — "they're not something you're going to ignore," she said — most people will recover on their own without treatment.
But now, let's turn to another parasite in the water that might as well come from a science fiction film. [Tiny & Nasty: Images of Things That Make Us Sick]Slide 5 of 21
Naegleria fowleriSlide 6 of 21
Naegleria fowleri — also known as the "brain-eating amoeba" — is as bad as its nickname implies. This single-celled microbe, which is found in warm freshwater (such as lakes, rivers and hot springs), causes a rare brain infection called primary amebic meningoencephalitis (PAM) and is almost always deadly. Between 1964 and 2014, there have been only 133 PAM infections in the U.S., and only three people have survived, according to the CDC.
But a person can only become infected if the microbe enters the body through the nose — in what sounds like something out of a sci-fi movie, the amoeba migrates along the olfactory nerve to the brain, where it begins to destroy the brain tissue. Drinking contaminated water, on the other hand, will not lead to an infection.
Infections don't only come from water. Next, learn what to watch out for underground.Slide 7 of 21
HistoplasmosisSlide 8 of 21