https://www.msn.com/en-us/health/other/neti-pots-nasal-rinsing-devices-linked-to-potentially-deadly-amoeba/ar-BB1jUb3w?cvid=fb3021b1a2a84484d7e9550fff44315a&ocid=winp2fptaskbarent&ei=17

It’s based on a study that only looked at 10 people, so nothing definitive.

Best Way to avoid these kinds of problems is to always use distilled (or vigorously boiled for 10 mins and used withing 24 hours) water, and always wash your pot immediately after with hot soapy water. Also make sure to dry thoroughly and if your neti pot is made of soft plastic, replace it after 3-4 months of use.