Understand Amoeba Risk in Warm Water

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Warm water provides the perfect environment for many infectious organisms, like bacteria and parasites, to live and breed. As the summer warms up, you may be tempted to swim in freshwater rivers or lakes in your area. But before you jump in, learn more about amoebas and the dangers they can pose.

What is an Amoeba?

An amoeba is a single-celled organism or parasite that can enter your body and cause illness. Certain types enter your body through your nose and then spread into your brain. Other types enter your gastrointestinal system when you swallow water.

Once inside your body, it can spread to almost any organ — and can be easily spread to other people through:

  • Contaminated food
  • Contaminated objects
  • Contaminated
  • Hands that aren’t properly washed
  • Other bodily contact

One particular type of amoeba, Naegleria fowleri, is especially dangerous. This amoeba can cause severe, often fatal, infections in the brain. Infection typically occurs when people go swimming in contaminated warm freshwater.

Amoeba infections are rare in the United States, but may be more likely in developing countries. If you’re traveling to other countries in South America or Africa, drink only bottled water and avoid swimming in freshwater.

What Are the Symptoms of Infection From Amoebas?

Symptoms may show up within a few days or few weeks of exposure and can include:

  • Diarrhea
  • Fever
  • Nausea
  • Vomiting

Naegleria fowleri causes more serious symptoms, such as:

  • Confusion
  • Hallucinations
  • Severe, sudden headache
  • Loss of balance or coordination
  • Seizures
  • Stiff neck

If you or a loved one experience these symptoms, seek medical attention right away at your nearest emergency department.

How Can I Prevent Infection From Amoebas?

While millions of people are exposed to Naegleria fowleri each year, only a handful will get an infection. You can take steps to reduce your risk for infection by avoiding swimming in freshwater and sticking to a properly treated pool instead.

If you do choose to swim or enjoy watersports in freshwater, it’s best to:

  • Avoid swallowing any water
  • Take a shower after you’re done enjoying the water
  • Wear nose clips

How is Infection from Amoeba Diagnosed?

Your doctor will ask questions about your symptoms and if you’ve recently been in a body of freshwater or been to a country where amoeba infections are common. They may also take a stool sample to verify the presence of amoebas.

If your doctor suspects Naegleria fowleri infection, an MRI or CT scan of your brain may be recommended to look for bleeding, and/or a spinal tap or lumbar puncture may be needed to get a sample of your spinal fluid.

Know Where to Go for Care

Most infections from amoebas — such as less serious amebiasis — can be treated by your primary care physician with antifungal medicines you can take in the form of a pill or get through an IV. These medicines kill the amoebas.

However, if you show signs of the more dangerous Naegleria fowleri infection, go immediately to the emergency department nearest you.

Learn more about AdventHealth emergency care and find the nearest location.

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