ABSTRACT
Respiratory tract infections include all those infections that normally transmit in the community as well as those that predominate in the health care industry. They are due to a variety of pathogens including viruses, bacteria, and fungi. Because most respiratory tract infections can be caused by inhalation as well as by direct contact, an unknown but possibly signiŸcant fraction of these infections can be ascribed to airborne microorganisms. This chapter focuses on respiratory infections that can be attributed to airborne pathogens but because it is difŸcult, if not impossible, to separate airborne from direct contact infections, all respiratory tract infections are included regardless of transmission mode.
