Cholera (CALL er uh) is a disease caused by Vibrio cholerae bacteria. Cholera gets into the body through contaminated water or food. Severe diarrhea from cholera can kill a person in just a few hours. Preventing cholera is as simple as providing safe, clean drinking water. Emergency water filter pouches help to do exactly this. They are filled with sugar syrup and salt. You drop the pouch into muddy water or even urine. After a few hours, the pouch fills with enough drinking water for a whole day. The flavor is like a sports drink. Which of the following could explain how an emergency water filter pouch makes a safe drink out of dirty water?
