A new, automatically controlled incubator for premature infants, supplied by air from out-of-doors, has afforded the opportunity of studying the effect of such a chamber on bacterial contamination of the air breathed by the infants. The incubator has been previously described.1
It is the purpose of the present report to discuss bacterial counts made on the air within the incubator, the air from out-of-doors and the air in different wards in which the incubators were placed, as well as the apparent effect of the reduction in bacteria on infant morbidity and mortality.
Extreme susceptibility to infection is inherent in premature infants. In spite of rigid nursery technic they become infected with discouraging facility. Usually the respiratory tract is attacked first, although the low resistance of the premature infant is not limited to this one system. Infection may begin elsewhere, as in the gastrointestinal tract or the skin, in the