What is botulism? Did it really cause Otto Warmbier to fall into a coma?

Otto Warmbier, a 22-year-old American student who was jailed in North Korea for alleged anti-state acts, has been released after more than a year in a coma that was said to be associated with botulism.

An official North Korean report has claimed that Warmbier has contracted foodborne botulism shortly after his trial in March 2016 and fell into a coma after taking a sleeping pill.

According to Dr. Sara Siavoshi, a California neuroscientist, botulism is a disease caused by a bacteria known as clostridium.

"This bacteria produces a toxin known as botulinum toxin. This toxin can be ingested by eating improperly canned foods, which allow the toxin to grow. It acts as toxin to the nervous system where it paralyses muscles," Siavoshi told Fox News.

Symptoms of botulism include difficulty breathing due to respiratory muscle weakness, blurred vision, difficulty swallowing and flaccid muscle paralysis. The World Health Organization has classified the condition as "rare" and noted that it is fatal in around three to five percent of cases.

Robert Glatter, an emergency physician at Lenox Hill Hospital in New York City, noted that the symptoms typically begin within 12–36 hours of eating contaminated food, but it can begin after six hours.

While the condition can be contracted through contaminated food, it can also come from wounds. Glatter noted that Botox, which is used to treat wrinkles and migraines, is a diluted form of the same toxin that causes botulism.

Siavoshi noted that botulism alone usually does not cause a person to fall into a comatose state, but it could potentially induce a coma when the patient is administered with a sedative.

"We know that if a patient does develop signs or symptoms of botulism, they usually do not become comatose from the toxin alone," Siavoshi explained.

"The toxin tends to affect the muscles and peripheral nervous system, not so much the brain. However, if one does contract botulism and already has difficulty breathing and is then administered a sedative agent on top of this, they may develop frank respiratory failure and fall into a coma due to oxygen no longer perfusing the brain," she continued.

Siavoshi said that individuals who suffer from botulism can be treated with antitoxins. She further explained that the patient must be observed for any breathing difficulties to avoid respiratory failure.

She stated that Warmbier would need to undergo a full neurologic evaluation if he has actually been in a coma for months. He would also need an extensive amount of physical and speech therapy to aid in his recovery if he exhibits "some degree of intact cognition."

Orlando Health physician Jamin Brahmbhatt noted that most of the patients who receive prompt medical care survive, adding that "time is of the essence," when seeking treatment.