Inactivation of Respiratory Syncytial Virus in Aerosol

Aerosols of respiratory syncytial virus were kept at different relative humidities (RH). Viability was studied by a plaque method. Virus recoveries 1 min. after aerosolization were highest at high RH. The stability of the aerosol was maximal at 60% RH. The total decay after 61 min. varied from 1.1 log. p.f.u. to 2.5 log. p.f.u., with peak values at 30% RH (2.3 log. p.f.u.) and 80% RH (2.5 log. p.f.u.), suggesting two processes with different kinetics. Oxidation was excluded as a cause of inactivation by experiments in pure nitrogen.