The Louisiana Department of Health and Hospitals issued its warning following a second death this year caused by Naegleria fowleri, the so-called brain-eating amoeba.
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"If you are irrigating, flushing, or rinsing your sinuses, for example, by using a neti pot, use distilled, sterile or previously boiled water to make up the irrigation solution," said Louisiana State Epidemiologist, Dr. Raoult Ratard. "Tap water is safe for drinking, but not for irrigating your nose."
http://www.nola.com/...erous_if_use.html