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You may have heard the term brain-eating amoeba, but what exactly is it? And does it actually eat your brain?
The scientific name for this amoeba is Naegleria fowleri. It’s a tiny, single-celled organism that’s found in warm freshwater and in soil.
Contrary to its common name, this amoeba doesn’t actually eat your brain. Still, a Naegleria infection can cause serious brain damage and swelling that often leads to death. The condition is called primary amebic meningoencephalitis (PAM).
While this amoeba is found around the world, cases of infection are actually quite rare. According to the Centers for Disease Control (CDC), only
Symptoms of a Naegleria infection can appear anywhere from 24 hours to 14 days after initial exposure to the amoeba.
The early symptoms are similar to those of meningitis and can include:
- severe headache
- nausea or vomiting
Once the initial symptoms develop, the infection progresses rapidly.
Later symptoms include:
- stiff neck
- light sensitivity
- loss of balance
The amoeba enters your body through your nose. It then travels from your nose and to your brain, where it begins to cause an infection. Contrary to popular belief, you can’t develop a Naegleria infection from drinking contaminated water.
Infection typically occurs when you’re swimming in a warm, freshwater lake or river. You can also encounter the amoeba in other water sources, such as contaminated tap water or improperly chlorinated pools, though this is rare.
In addition, Naegleria loves the heat and thrives in warm or hot water, so infections tend to happen during the summer months, especially amid extended heat waves.
The Naegleria amoeba can be found worldwide. In addition to the United States, infections have been reported in Australia, Africa, Asia, Europe, and Latin America.
In the United States, Naegleria is mostly found in the southern states where the climate is warmer. However, it’s also been found in northern states, such as Minnesota and Connecticut.
In recent years, there have been a few news stories of people developing Naegleria infection after using neti pots to irrigate their sinuses.
These cases weren’t due to the neti pot itself. Instead, they were caused by using contaminated tap water in neti pots, which allowed the amoeba to enter people’s noses.
If you use a neti pot, these tips can help you avoid an infection:
- Purchase water that’s labeled as “sterile” or “filtered” for use in your neti pot.
- Use tap water that’s been boiled for at least one minute and allowed to cool down.
- Use a water filter that’s labeled as meeting NSF standard 53. You can shop for these online.
If you think you may have a Naegleria infection, make an appointment to see your healthcare provider right away. Be sure to let them know if you’ve been in any freshwater recently.
Depending on your symptoms, they may collect a sample of cerebrospinal fluid (CSF) for testing. CSF is the fluid that surrounds and protects your brain and spinal cord. It’s collected through a process called a lumbar puncture. This is done by inserting a needle between two of the vertebrae in your lower back.
A lumbar puncture can provide information on CSF pressure as well as levels of blood cells and proteins, which are abnormal in people with PAM. The actual Naegleria amoeba may also be visible under the microscope in a CSF sample.
Because the infection is so rare, there are limited studies and clinical trials regarding effective treatments for Naegleria infection. Most treatment information comes from of studies within a laboratory or through case studies.
One promising treatment is the antifungal medication amphotericin B. It can be given intravenously or injected into the area around your spinal cord.
Another new drug called miltefosine appears to be useful for treating Naegleria infections.
Additional medications that may be given to treat Naegleria infection include:
Infection with Naegleria is very rare, but it’s always a good idea to take a few precautions when you’re spending time in water.
Here’s a look at some tips to reduce your risk:
- Avoid swimming in or jumping into freshwater lakes, rivers, or streams, especially during warm weather.
- If you do plan to swim in freshwater, try to keep your head above water. Consider using nose clips or holding your nose shut with your fingers.
- Try not to disturb or kick up the sediment when swimming or playing in freshwater.
- Make sure to only swim in pools that have been properly disinfected.
Infection with the amoeba Naegleria fowleri can cause a severe and often fatal condition called primary amebic meningoencephalitis. Infection occurs when the amoeba enters your nose and travels to your brain.
Naegleria infection is extremely rare. However, if you regularly swim in freshwater during warm weather, you may want to consider taking some steps to reduce your risk.