After years of severe stomach pains and other painful symptoms, Jackie discovers she's been suffering from Schistosomiasis, or snail fever.

Only 20 percent of infected individuals will show symptoms of Zika, making it often misdiagnosed. To make matters worse, it can result in devastating birth defects if a woman catches before or during pregnancy.

Charlye Hebert has been experiencing nausea, vomiting and diarrhea for months. Despite an initial diagnosis and treatment for stomach ulcers, her symptoms have yet to subside.

Doctors and family are stunned when they discover the cause of Kennedy's poor health is due to an extreme allergy to nickel, which can be traced to the metal braces on her teeth.

Xander's condition takes a devastating turn when his skin starts peeling off his body.

Now that doctors know what's wrong with Xander, they put him on life support to give him the best chance of recovery.

After spending two months in a coma as a result of a Group A Streptococcus infection, Katy wakes up to the devastating news that all four limbs had to be amputated in order to keep her alive.

After complaining about pain on his head, 8-year-old Andrew is rushed to the ER, where doctors remove a botfly larva from his scalp.

When doctors cannot find anything in his mouth, biology professor John Allen takes matters into his own hands and extracts a rare parasite called Gongylonema pulchrum.

After suffering from an array of symptoms for months, Al Ceccarelli is diagnosed with Strongyloides, a disease caused by parasitic worms found in tropical climates.

As soon as doctors make an incision near Paul’s eye, out pops a larva.

An ovarian teratoma removed from Kira’s body featured hair, teeth, tissue and other cells, resulting in her erratic behavior and sickness.

Sam's worsening flu-like symptoms takes him to the emergency room, where his urine indicates something dangerously wrong with his renal system.

With Brianna's head abrasion getting worse, her parents rush her to the ER where a dermatologist hears something terrifying coming from her scalp.

When a high school football star begins to experience odd symptoms, his parents take him to the hospital.

Stephanie noticed her 4-year-old son, Alex, came home with less energy than usual. But what seemed like the result of a long day at school quickly turned into a race to the emergency room.

See why the new season of Monsters Inside Me may be the most terrifying one yet.

What is believed to be a finger injury turns into something much worse when 1-year-old Evelyn begins to experience labored breathing, sweating and vomiting.

Neuropsychiatrist Garrett finds himself in the hospital as a patient when a mysterious illness has caused his vital organs to start shutting down.

After years of severe stomach pains and other painful symptoms, Jackie discovers she's been suffering from Schistosomiasis, or snail fever.

After finding out what’s wrong with her eye, Melanie is forced to administer medication that may cause more harm than good.

Erica’s postpartum joy is short lived when she begins to suffer from mysterious pain not long after giving birth to her daughter.

Weeks after delivering her baby via caesarian section, Erica is shocked to discover the cause of her subsequent intestinal troubles.

When a teenager named Jordan begins to experience repiratory issues, his Mom races him to the hospital. Doctors diagnose him with a type of pneumonia … and both Jordan and his parents are forced to face the possibility of death.

A software programmer is admitted to a hospital and begins to show a strange symptom... speaking only in computer code! His wife fears he has gone insane when doctors discover that he has the most dangerous parasite in the world!

A teenager named Jordan's contracted the deadly Hantavirus - a dangerous virus that can be contracted from infected mice.

Boil-like legions lead to a diagnosis of lung cancer, just in time for Christmas. But during surgery, doctors are surprised to find a different sort of infection.

After being born several weeks premature, baby Lillian's development takes a dangerous turn when she begins to suffer from seizures.

A college student gets an oozing rash that grows rapidly! He thinks it is a staph infection but when it grows to cover most of his arm, he knows something worse is going on!

Tara keeps feeling stabbing pains in her scalp, so she investigates the Internet for answers. What she finds is almost unbelievable - botflies. She decides to cut open her scalp.

A seemingly harmless cat scratch leads to a rash that feels "alive"! A dermatologist confirms that the rash is really a case of hookworm and if it isn't stopped soon, it could turn deadly!

When medicine fails to stop the Cytomegalovirus inside baby Lillian's brain, her parents are forced to make an agonizing decision that could mean life or death for their daugther.