Isolation of amoebae from the air.

Abstract

Summary In preliminary studies in a hospital in Manchester in which tissue culture was used for cultivation, Hartmannella castellanii was isolated from the air on two occasions and from surface samples on one. Water agar plates with a lawn of Klebsiella aerogenes were exposed in a slit sampler, or as settle plates, in and outside a laboratory in London and the following amoebae were isolated: 12 strains of H. castellanii, 7 of H. leptocnemusjagricola, 5 of H. glebae, 1 of H. agricola, 3 of Naegleria sp. and 1 of Schizopyrenus sp. In outdoor air an average of one amoebic cyst of any species was found in 322 cu. ft (9-1 m3) and one cyst of H. castellanii in 644 cu. ft (18·2 m3). All the isolates of H. castellanii damaged HeLa cells. Four that grew poorly or not at all at 37°C showed a marked cytopathic effect at 33°C. An identification key is given.