We can use water purifiers and not have to worry about the water we drink. There are different ways to purify water. If we purify the water the germs and the bacteria are gone, then the water we drink will be good for us and we won't have to worry about diseases.
Another way to purify water is to use a water pump that purifies water as you pump it. Then, the water is drinkable.
There are also water bottles with filters in them, so they filter the dirty water you are drinking, as you drink your water.
You can also boil water and kill all possible germs that are in the water. All you have to do is put a pot of water over a stove or fire and wait for it to boil.