10 Most Terrifying Parasites Ever

Bedbugs have officially invaded. The CBS News Early Show reports that across the country, infestations are becoming so common exterminators are having a hard time keeping up. In New York City, the crawly blood-suckers are being spotted in upscale lingerie shops and trendy boutiques - one thing about these blood suckers, they have taste.

Bedbug

Brown and about the size of an apple seed, Cimex lentacularius hides during the day and comes out at night, (shown piercing the skin of its host and drinking its fill. The bites don't spread disease but leave red, itchy welts. Bedbugs are so hard to exterminate that some people simply throw out their furniture, clothing, and bedding.

Botfly

Botflies aren't easily confused with common houseflies - they're hairy and about twice as big. They lay their eggs on a mosquito, which then lands on a person. Once hatched, the larvae invade the skin of the unlucky host (as seen in this photo).

Botfly

The babies proceed to eat their way to the muscle, leaving a sore around the breathing hole they make in the skin. Here's the truly disturbing part: Infected people report being able to feel and even hear the maggots moving about. Surgery is often necessary to remove the organisms.

River Blindness

If you're planning a safari, be on the lookout for black flies, which can cause an illness known as river blindness. This swollen hand got that way after being bitten by a black fly infected by the nasty Onchocerca volvulos. Swollen flesh is one symptom of river blindness - others include eye sores and, eventually, blindness. Worldwide, it is the #2 cause of blindness, with about 90 percent of cases occurring in Africa.

River Blindness

This microscopic amoeba has a long name - Acanthamoeba keratitis - and a long rap sheet to match. If you wear contacts and like to camp, be extra careful about how you clean and insert your lenses. Make sure your hands are clean when you touch your eye, because acanthamoeba can invade the cornea, causing an infection that can lead to blindness. Acanthamoeba is common in nature and can be found in water, soil, and air.

Sandfly

If you're planning a vacation to South America, the Middle East, southern Europe or any of the 88 countries where sand flies like to hang, don't forget the insect repellent. Small and silent, the female sand fly can transmit a parasite that causes leishmaniasis. The bite is so small you might not even know you've been bitten - at first.

Sandfly

There are two ways to get sick. Cutaneous leishmaniasis causes severe skin sores, while visceral leishmaniasis attacks the internal organs. You'll know you have the skin kind within a few weeks or months of being bitten. If you get the kind that attacks your insides, it can be months or even years.

Leech

This bloody mess is the doing of a common leech. And if a leech can do that kind of damage, imagine what Tyrannobdella rex - the name means "tyrant leech king" - can do with its enormous teeth. So far he's been spotted in the Upper Amazon in Peru - as if people who live in the rain forest don't have enough don't scary critters to worry about.

Threadworm

This little nasty has a foot fetish. The threadworm, a.k.a. Strongyloides, is oddly attracted to the soles of the feet. Maybe that's why mom always made us put on shoes in the backyard. The larvae enter the bloodstream and travel to the lungs, where they break through the tissue and move up to the throat.

Threadworm

They might give you a clue that they've made your body "home" by the pneumonia-like symptoms you get as larvae move through the lungs. Or you might just get itching and swelling, and sometimes a red line under the skin that marks when they've been on the move. Untreated infection can lead to organ failure and death.

Lungworm

It's summer and you're watching your diet - good for you. But watch out for lettuce. If you eat raw produce that's hiding a tiny snail or slug, you might get infected with a sneaky little beast known as the rat lungworm. Seems snails and slugs can get the worm from eating rat feces - and then pass it along to humans.

Lungworm

Is escargot your thing? Make sure it's fully cooked. Is your kid a fearless eater? Warn him to stay away from garden slugs - children have been infected by eating them on a dare.

Tapeworm

Planning a stay-cation? Don't be lulled into a sense of false security. Make sure you cook your BBQ thoroughly so you don't end up feeding your loved ones a side of tapeworm. Tapeworms attach to the intestinal wall, where they feed on nutrients from digested food.

Tapeworm

Tapeworms are looong.Typically, they grow to about nine to 15 feet, though some reach 50 feet. Often the host doesn't even know it's there until the worm gets really big. Expect the symptoms, if you have any, to be flu-like: headache, nausea, stomach cramps.

Babesiosis

Maybe the chilly waters off Cape Cod are more your style. Still, don't be cavalier about the ticks. In addition to the well-known Lyme disease, tick-borne illnesses include babesiosis, an illness sometimes called the Malaria of the North. Fire Island, New York, as well as Nantucket and Martha's Vineyard in Massachusetts are favorite haunts. If you get bitten by this bug, symptoms can include fevers and shaking chills.

Malaria

Lucky you, you have tickets to the tropics! But watch for mosquitoes. Some females can inject you with the malaria parasite, which takes up residence in the liver. Left untreated, the parasites multiply in red blood cells. At best you'll feel like you have a bad cold. Worst-case scenario? Coma and even death.