Another dangerous amoeba is thought to be associated with neti pots and nasal rinses.Here's what you need to know

new york – Scientists have known for years that neti pot users can become infected with brain-eating amoebas if they use the wrong type of water. On Wednesday, researchers linked a second type of deadly amoeba to nasal rinsing.

The Centers for Disease Control and Prevention has released a report linking Acanthamoeba infections to neti pots and other nasal irrigation devices for the first time.

Officials also once again warned that flushing the nasal passages with regular tap water can have extremely rare but potentially fatal consequences.

“We published this study because we wanted people to be aware of this risk,” said Dr. Julia Haston of the CDC.

A neti pot is one of the well-known nasal irrigation tools. It looks like a small teapot with a long spout and is usually made of ceramic or plastic.

The user fills it with saline and pours the liquid into one nostril. It exits through the other end and flushes allergens and other nasty pollutants out of your nasal passages.

Neti pot use in the United States has skyrocketed in recent decades, due in part to the increasing prevalence of allergies and other respiratory illnesses, market researchers say.

There are other ways to clean the nasal passages, such as specially shaped cups or squeezable plastic bottles.

Although tap water in the United States is treated to meet safe drinking standards, it may still contain low levels of microorganisms. While drinking or cooking with tap water is usually not a problem, using tap water for other purposes, such as humidifiers or nasal irrigation, can pose additional risks.

CDC officials cited a 2021 study that said about one-third of U.S. adults incorrectly believe tap water is free of bacteria and other microorganisms. Nearly two-thirds of people say tap water is safe to use to clean their sinuses.

The CDC recommends using boiled, sterile or distilled water.

If tap water is used, it should be boiled for at least one minute, or three minutes at high altitudes, before cooling and use, officials said.

More than a decade ago, health officials linked nasal rinsing to deaths in the United States from a brain-eating amoeba named Naegleria fowleri. More recently, researchers have begun to focus on nasal irrigation as a common theme in diseases caused by another microscopic parasite, Acanthamoeba.

Although Acanthamoeba causes many different types of disease, it remains dangerous, with a fatality rate of 85% in reported cases.

“These infections are very serious, even life-threatening,” said Haston, lead author of the report published in the journal Emerging Infectious Diseases.

The new study focused on 10 patients who developed the disease between 1994 and 2022, three of whom died. Although researchers said they do not know how the patients were infected, they noted some commonalities. All of them had weakened immune systems and were rinsing their noses.

Seven patients reported nasal irrigation to relieve chronic sinus infections, and at least two of them used a neti pot. Two other patients performed nasal gargles as part of a traditional Indian cleansing ritual.

This amoeba is found naturally throughout the world. environment — in lakes, rivers, seawater, and soil.

It can cause skin and sinus diseases, and it can also infect the brain and cause deadly inflammation. This microorganism is also thought to be associated with non-fatal but vision-threatening eye infections, sometimes through contaminated contact lens solution.

U.S. health officials have identified about 180 cases of infection with this single-celled organism since the first infection was diagnosed in 1956.

In most cases, researchers don't know exactly how people became infected. But as they investigated cases over the past few decades, CDC researchers increasingly received information that nasal irrigation was used in many cases, Haston said.

Studies have shown that it is also commonly found in tap water. A study conducted in Ohio in the 1990s found that more than half of the tap water samples examined contained amoebas and similar microorganisms.

“It's very likely that we're all constantly exposed to Acanthamoeba,” she says.

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