Isolation of free-living amoebae from soil and vegetables; study of the morphology and pathogenicity of the isolated strains
Ciurea van Saanen, M.
Revue Medicale de la Suisse Romande 101(3): 229-238
In the neighbourhood of Lausanne, Switzerland, amoebae were isolated in all of the 5 soil samples (peat, lawn, leaf mould and 2 vegetable gardens) tested. After cultivation at 28 and 37 deg C, trophozoites which developed at 37 deg killed 100% of mice in 3 to 7 days after intra-nasal inoculation. These were identified by SEM as Naegleria fowleri and Acanthamoeba culbertsoni. Amoebae developing at 28 deg C were non-pathogenic to mice and were identified as N. gruberi and A. rhysodes. Amoebae were also isolated in washing water from vegetable samples in the Canton of Vaud. Amoebae which developed at 37 deg C killed 100% of mice and were identified as A. culbertsoni; none of those developing at 28 deg C (N. gruberi, A. castellanii, Hartmannella glebae, A. rhysodes, A. polyphaga, A. palestinensis and Schizopyrenus sp.) was pathogenic. No cases of amoebal meningo-encephalitis have been reported from Switzerland.