There are no means yet known that would control naturally occurring Naegleria fowleri levels in lakes and rivers making prevention difficult. Because of this, swimmers and other recreational water users should assume that there is always a low level of risk whenever they enter warm freshwater lakes, rivers, and hot springs (for example, when swimming, diving, or waterskiing), particularly in southern-tier states.
The only certain way to prevent a Naegleria fowleri infection due to swimming is to refrain from water-related activities in warm freshwater. Personal actions to reduce the risk of Naegleria fowleri infection should focus on limiting the amount of water going up the nose.
These actions could include:
- Hold your nose shut, use nose clips, or keep your head above water when taking part in water-related activities in bodies of warm freshwater.
- Avoid putting your head under the water in hot springs and other untreated thermal waters.
- Avoid water-related activities in warm freshwater during periods of high water temperature.
- Avoid digging in, or stirring up, the sediment while taking part in water-related activities in shallow, warm freshwater areas.
These recommendations make common sense but are not based on any scientific testing since the low numbers of infections make it difficult to ever show that they are effective.
Source: http://www.cdc.gov
Naegleria Fowleri 