Minimizing pathogenic bacteria, including spores, in indoor air

Five experiments were conducted to assess whether aerosolized bacteria, including spores, respond like particulate contaminants to the primary (electrical) forces that control the distribution of small particulate contaminants in indoor air. Such response would suggest an approach to minimizing infection in offices, hospitals, nursing homes, and other facilities. It also would have implications for protection against intentionally introduced pathogenic bacteria, including spores. The experiments used two different genera and five different strains of bacteria, including spores. Micrococcus luteus was used as a surrogate for Gram-positive cocci, because M. luteus is similar in size, shape, and cell wall composition to staphylococci, streptococci, and enterococci. Similarly, spore-forming and vegetative Bacillus subtilis were used as surrogates for Gram-positive bacilli such as Bacillus anthracis. The experiments were conducted in a dedicated aerosol physics test facility with culture-based measurements made at timed intervals. The results indicate that the organisms do respond like particulate contaminants to typical electrical forces in a room.