Microbiologic air contamination and building-associated illness

Summary Microbiologic air contamination plays, among other factors, a role in building associated illnesses i.e., hypersensitivity diseases, bacterial and fungal infections, sick building syndrome. Airborne microorganisms are separated into obligate parasites, such as the viruses and a few bacteria, that must find a suitable host within a brief period, and facultative saprophytes that are usually found in living hosts an/or in the environment (primary and opportunistic pathogens). The etiology of hypersensitivity diseases is biological allergens such as those from fungi (moulds), bacteria,Amoebae and other protozoa. Humidifiers, cold air coils and porous material belonging to mechanical ventilation system can all be reservoirs/amplifiers/disseminators for living organisms, allergens or other microbial products. Legionella is an ubiquitous bacterium in the environment. Bioaerosols from potable water and air conditioning components appear to be the source of most human infections with this organism (Legionnaire's disease and Pontiac fever).Aspergillus fumigatus has a risk of penetration indoor but affects only people with seriously impaired immunity. Responsibility of airborne moulds, bacterial endotoxins or mycotoxins in sick building syndrome complaints is unclear. Design, operation and maintenance of ventilation systems are fundamental to assure well-being to building occupants.