Although rare, amoebas found in untreated water can cause fatal brain infections if they get in your nasal passage[0], via neti-pots or swimming, for example.

Although rare, amoebas found in untreated water can cause fatal brain infections if they get in your nasal passage[0], via neti-pots or swimming, for example. [0] https://www.ijidonline.com/article/S1201-9712(18)34525-9/pdf https://www.ijidonline.com/article/S1201-9712(18)34525-9/pdf