So this explained why only the masses were getting sick.

After they discovered this, they knew the next thing to do was to purify the river by getting the specks of dirt out of the river. And to do this, they needed some highly skilled swimmers, that would swim deep into the river and get out the dirt that contaminated their water. But they didn't have them in their town, they can only get them in a foreign town for a huge amount of Money.

The town head promised to get the swimmers as soon as possible.

Months passed and nothing was done to get the river cleaned.