The story of Aimee Copeland—the 24-year-old Georgia woman fighting for her life—put necrotizing fasciitis on the map this week. A rare condition, it is a bacterial infection that tears through the body's fascia, destroying all tissue in its path. It has earned the nickname “flesh-eating disease”—and left many people wondering if such a horrible fluke could ever befall them, too. The Daily Beast rounds up a list of bizarre conditions that rarely strike, but still manage to terrify. Hypochondriacs, beware.

Necrotizing Fasciitis Necrotizing fasciitis—often referred to as “flesh-eating disease”—is an infection that can be caused by any one of many different kinds of bacteria. It results when bacteria penetrate deeply below the skin, into the spaces surrounding the body’s musculature. Once it has done so, it’s able to spread rapidly, producing toxins and proteins that dissolve the body’s tissues. Immediate treatment and aggressive surgery—often including amputation—are crucial to the treatment of this condition, which, if left unattended, is lethal.

Paralytic Shellfish Poison (PSP)Who’s at risk? Anyone who eats shellfish, alas. This disease is caused by naturally occurring toxins that are found in the tissue of some shellfish. The first symptom of PSP is a tingling in the fingers and toes, followed by loss of limb control, and then abdominal and chest paralysis, impeding the ability to breathe. Death can occur within 30 minutes. There is no known antidote. The infected shellfish do not appear or taste differently than uninfected shellfish; the toxin can only be detected in a lab.

Premature aging syndrome (Progeria) Progeria is a rare genetic condition that causes rapid and premature aging in children. Kids fail to grow in the first year of life; they lose hair and eyebrows, and their faces are wrinkled and shrunken, giving them an elderly appearance. The condition has no cure and most people who have it do not survive past adolescence.

Acanthamoeba keratitisA rare condition in which a microscopic amoeba, the acanthamoeba, invade the cornea of the eye, causing severe pain and even blindness. The amoeba are extremely common—they’re often found in tap water. In the United States, roughly 85 percent of cases occur in contact lens users, because scratches to the cornea as well as improperly sterilized contacts increase the risk of amoeba invasion.

River Blindness Disease (Onchocerciasis)It is the world’s second leading infectious cause of blindness, named for its most common site of infection: near fast-moving bodies of water where the blackfly deposits its larvae. The larvae produce parasitic worms that can enter the human body and take up residence for as long as 14 years. Once inside the body, the worm can lay millions of larvae, which cause severe and diverse symptoms, which can include depigmentation, blindness, itching, and elephantiasis.

Fibrodysplasia Ossificans Progressiva (Stone Man Syndrome)Extremely rare and disabling, this seemingly unthinkable condition causes bones to grow in muscles, tissue, and connective fiber; bone forms across joints, forming a second skeleton of sorts and increasingly restricting movement, until the afflicted patient becomes statuesque in their immobility. The condition is genetic and there is no treatment. The growth of new bone formation is spurred by any injury to the body. There are roughly 700 known cases worldwide, or one out of every 2 million people.

Prion Diseases (transmissible spongiform encephalopathies)Prion diseases are a family of related neurodegenerative diseases that affect animals and humans. They are believed to be caused by prions, or toxic agents that cause certain proteins—mostly in the brain—to fold abnormally, to devastating effect. Examples of prion diseases include:

Fatal familial insomnia—a highly genetic condition, in which people become unable to fall asleep. Onset is typically during middle age, which is characteristic of the long incubation periods most prion diseases show.

Kuru—an exceedingly rare condition, Kuru occurred at epidemic proportions among the Fore people of New Guinea in the 1950s. It came from their practice of eating the deceased among them—and catching the prion disease either from the cannibalism itself or from close contact with the infected flesh.

Candiru fish—aka, “the penis fish”A native of the Amazon River, this small, nearly translucent fish can grow up to six inches long. It has become a terrifying legend: the candiru seeks out orifices where it can enter living bodies and feed on the host’s blood. Even worse, the candiru is allegedly able to travel from the river and up a stream of human urine, then into the urethra, where it lodges and swells. Every man’s worst nightmare. The first documented case of the removal of a candiru fish from a urethra was not until 1997, raising the possibility that this outcome is more myth than medical fiasco. Either way, it’s probably best not to piss into the Amazon.