An Experimental Model of Primary Amoebic Meningoence phalitis Due to Naegleria australiensis in Iran

BACKGROUND: The main aim of the present research was to develop the experimental meningo encephalitis due to Naegleria australiensis isolated from geothermal water sources in mice model, November 2017 in Iran. METHODS: Naegleria australiensis was isolated from geothermal water sources in northern Iran. The number of amoebae was adjusted to be 1×10(4)/ml amoebae. The experimental infection was done using 3 wk old male (BALB/c) mice. Seven animals were used for experimental amebic infection and one animal was selected for the control. Intranasal (IN) and intracerebral (IC) inoculation of amoebae were done. The mice were then monitored on daily observation and as soon as they present any brain involvement they sacrificed. The brain of all animals was then dislocated and passaged in non-nutrient agar. RESULTS: One mouse out of seven infected mice were showed clinical symptoms of meningoencephalitis. Within few hours of culture of the brain, many vegetative forms of amoebae were detected in plate culture. The other infected animals and control mice showed no clinical symptoms until day 14. After 14 d all the animals sacrificed. The culture was negative up to one month. CONCLUSION: The lack of brain involvement of other animals in the present study could be due to animal immune system or it may be possible that the amoebae did not reach to olfactory bulb of nostrils.