The survival ofEscherichia coliin an aerosol at air temperatures of 15 and 30 °C and a range of humidities

Abstract

SUMMARYThe survival ofEscherichia coliin an aerosol was studied at several temperatures and over a range of relative humidities using a Henderson apparatus.Death occurred in two phases, the first lasting approximately 1 min; in the second the number of viable microorganisms declined exponentially.E. coliwas robust and remained viable for many hours. Death was most rapid at low humidities (< 50% r.h.) at 15 and 30 °C, with half-lives of 14 and 3 min respectively. In humid conditions the half-lives were much longer, approximately 83 and 14 min respectively.Based on this work, preliminary recommendations for the climate of livestock buildings can now be given to control the airborne spread ofE. coli.