Naegleria fowleri infection acquired by mice through swimming in amebae-contaminated water

Area of Science:

• Microbiology
• Infectious Diseases
• Neuroscience

Background:

• Naegleria fowleri is a free-living ameba known to cause primary amebic meningoencephalitis (PAM), a rare but severe brain infection.
• Understanding the pathogenesis and transmission routes of N. fowleri is crucial for developing effective prevention and treatment strategies.

Purpose of the Study:

• To investigate the susceptibility of mice to Naegleria fowleri infection through swimming exposure.
• To establish and validate a mouse model for studying experimental primary amebic meningoencephalitis.

Main Methods:

• Groups of mice were exposed to varying concentrations of Naegleria fowleri (10^2 to 10^6 amebae/ml) in water.
• Exposure durations ranged from 2.5 to 20 minutes.
• Mouse mortality and infection outcomes were recorded.

Main Results:

• Mouse mortality varied significantly, ranging from 0% to 70%.
• Mortality was directly correlated with both the concentration of Naegleria fowleri and the duration of swimming exposure.
• Fatal naeglerial infections were observed in mice exposed to the amebae.

Conclusions:

• Swimming exposure to Naegleria fowleri can lead to fatal infections in mice.
• The mouse model is confirmed as a viable tool for studying experimental primary amebic meningoencephalitis.
• This study provides further evidence for the pathogenicity of N. fowleri in a mammalian model.