The survival of bacteria in dust. II. The effect of atmospheric humidity on the survival of bacteria in dust

Abstract

Dust from scarlet-fever wards was exposed to a controlled range of atmospheric humidities by enclosure in metal boxes containing anhydrous calcium chloride and saturated solutions of potassium carbonate, sodium nitrite, potassium bromide and sodium sulphate.The death-rate of total organisms,Staphylococcus aureusandStreptococcus pyogenesin the dust was assessed by periodic sampling of series of twenty 10mg. portions. A positive correlation between atmospheric humidity and death-rate was observed for the three groups of organisms counted in three specimens of dust.