Some of these small parasites have been mutating and are now resistant to many over-the-counter medications.
The U.S. Supreme Court is set to rule next month on whether to ban life without parole for minors convicted of murder.
The cases center on two 14-year-olds — one in Alabama, the other in Arkansas.
The decision could have a ripple effect across the country, affecting more than 2,000 prisoners, if the Supreme Court decides to ban life without parole for all juvenile offenders.
One of those prisoners is 37-year-old Joe Donovan of Massachusetts, who has been behind bars for 20 years.
This segment was produced by Deb Becker.