Missouri DHSS Confirms Rare Case of Brain Infection

Naegleria fowleri is a microscopic single-celled free-living ameba that can cause a rare deadly infection of the brain called primary amebic meningoencephalitis (PAM), also known as “brain-eating” infection. Typically, fewer than 10 people a year in the United States get PAM.

The Missouri patient is currently being treated for PAM in an intensive care unit of a hospital, and currently, no additional suspected cases of PAM are being investigated in Missouri.

The ameba is common and naturally present in warm freshwater such as lakes, rivers and ponds; however, PAM is extremely rare. Between 1962 and 2024, there were 167 reported cases of PAM in the United States.

The source of the patient’s exposure is currently being investigated by public health officials. While not confirmed, preliminary information implies the patient may have been water skiing at the Lake of the Ozarks days prior to becoming ill. Recreational water users should assume that Naegleria fowleri is present in warm freshwater across the United States; however, infection remains very rare.

Although a rare occurrence, people become infected by Naegleria fowleri when water containing the ameba enters the body through the nose from freshwater sources. The Naegleria fowleri ameba then travels up the nose to the brain where it damages the brain tissue. This infection cannot be spread from one person to another, and it cannot be contracted by swallowing contaminated water.

People can take actions to reduce the risk of infection by limiting the amount of water going up the nose. These actions could include:

Those who experience the following symptoms after swimming in any warm body of water should contact their health care provider immediately as the disease progresses rapidly:

For more information about Naegleria fowleri, visit the CDC’s webpage.