A Doctor Says a Woman Died From a Brain-Eating Amoeba After Using a Neti Pot. Are They Safe?

A Seattle woman died earlier this year after becoming infected by the brain-eating amoeba Balamuthia mandrillaris, Fox Q13 reports. And doctors believe her infection started in an unusual, and seemingly innocuous, way: using a neti pot filled with tap water.

Terrifying as it may be, the Seattle woman’s case is extremely rare. Worldwide, only about 200 cases of Balamuthia infection have been diagnosed since the amoeba was first discovered in 1986, according to the Centers for Disease Control and Prevention (CDC). Nonetheless, the incident may spook even devoted neti pot users.

So are neti pots safe? TIME asked Dr. Ben Bleier, an associate professor of otolaryngology at Harvard Medical School and Massachusetts Eye and Ear.

What are neti pots used for?

Neti pots, which resemble tiny teapots, are used to flush mucus and debris from the nasal cavity, often when a person is suffering from allergies, sinus problems or common colds. After tilting your head sideways, you can use the pot to pour a small amount of a saline solution into your upper nostril, letting it drain through the lower nostril as you breathe through your mouth.

Are neti pots safe?

Neti pots are safe and effective for the vast majority of people, as long as they’re used correctly, Bleier says.

“Anybody with a normal nasal cavity, or even someone who’s had sinus or nasal surgery but has a healed nasal cavity, can use these safely, as long as they’re using them within the proper guidelines,” Bleier says. “Those guidelines include using either boiled or distilled water” — not tap water — “and making sure the bottle itself is clean, either with hot soapy water or by microwaving it before use or some combination of those.” (If you do boil your water, make sure it has adequately cooled before use.)

Bleier notes, however, that neti pots may not be the best way to clear nasal congestion. “We actually more frequently recommend using a squeeze bottle,” Bleier says. “They’re slightly different. The neti pot relies only on gravity, and the type of flow you achieve is mainly down the bottom part of the nasal cavity. The irrigation bottles tend to get a little better coverage of the nasal cavity, so they’re a little bit more effective.” Bleier says he doesn’t recommend any particular brand of irrigation bottle, but some common ones are NeilMed, Ocean and Ayr.

Who shouldn’t use neti pots?

Most people only need to perform nasal irrigation when they’re sick or congested, since the nose typically does a good job of cleaning itself naturally, Bleier says. The only people who categorically should not use neti pots or irrigation bottles are those with fresh trauma to the nose, Bleier says, since the fluid can irritate the injury or cause infections to spread.

People should be particularly cautious because of the nose’s proximity to the brain, Bleier says. “The reason that you can get brain infections by nasal irrigation, as opposed to swallowing tap water or bathing in tap water, is that the roof of the nose is one of the only parts of the human body where there’s a direct extension of the brain and central nervous system into the outside world,” he explains.

Still, Bleier emphasizes that such cases are exceedingly rare, and that nasal irrigation is not something to fear. “We still think it’s very, very safe to use,” he says. “You just have to do it in a clean way.”