The case of a woman who died from a brain-eating amoeba after using filtered tap water to clear her sinuses has some wondering how to safely use neti pots.

The woman, 69, was using tap water filtered using a Brita Water Purifier in a neti pot, according to a report published in the peer-reviewed International Journal of Infectious Diseases. She died of died from Balamuthia mandrillaris, an amoeba that might live in water and can travel to the brain, causing deadly infection.

This isn't the first time someone died from an amoeba believed to be in neti pot water. In 2013, a Louisiana man in his 20s died from another type of brain-eating amoeba, Naegleria fowleri, after using tap water in his neti pot.

A neti pot is a teapot-shaped container used to rinse out sinuses to relieve congestion often related to allergies and colds. Most people use neti pots at home, filling them up with a saltwater solution and then pouring the solution (using the neti pot) into one nostril so that it runs through the sinuses and out the other nostril.

Neti pots require sterile water. What is sterile?

Never use tap water in a neti pot, according to recommendations from the Food and Drug Administration and the Centers for Disease Control and Prevention. The CDC advises several ways for making sure water is sterile: Boiling and then cooling the water; using distilled water; filter the water using a filter that removes amoebas; or use chloride bleach to treat the water.

More:Woman dies from brain-eating amoeba after using neti pot with filtered tap water

Using distilled or cooled boiled water is the preferred method. Distilled water can be bought at most grocery stores and will be labeled distilled or sterile. To use boiled water, make sure the water has been boiled for one minute and then left to cool. At elevations above 6,5000 feet, the water should be boiled for three minutes, according to the CDC.

Filtered water is the next best option, but the filter being used must read “NSF 53” or “NSF 58” or contain the words “cyst removal” or “cyst reduction."

For anyone unable to use water sterilized or filtered using the above methods, use a double dose of chlorine bleach disinfectant and let it stand for 30 minutes. If the water is murky, strain it through a clean cloth, paper towel or coffee filter before treating it, the CDC recommends.

Keep the neti pot clean.

Wash and dry your hands before using the neti pot, and make sure the neti pot itself is clean and dry between uses, the FDA recommends.

It might not be safe for young children

Very young children might not be able to tolerate nasal rinsing using a neti pot, the FDA warns. Talk to your child's pediatrician before using the device.

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