An air sanitization system including a reactive oxygen species generator, a variable speed fan, a pathogen sensor and a controller. The reactive oxygen species generator generates reactive oxygen species from an oxygen-containing gas and discharges the reactive oxygen species to a conditioned space. The variable speed fan directs the oxygen-containing gas to the reactive oxygen species generator at a controlled speed. The pathogen sensor senses a level of airborne pathogens in the conditioned space and generates a signal indicative of the level of pathogens sensed. The controller receives the signal from the pathogen sensor and varies the speed of the variable speed fan in response to the signal to decrease a speed of the variable speed fan in response to an increase in the level of airborne pathogens sensed by the pathogen sensor.