A 2-year comparative study of mold and bacterial counts in air samples from neutral and positive pressure rooms in 2 tertiary care hospitals.

Immunocompromised patients are at risk of invasive fungal infection. These high-risk patients are nursed in protective isolation to reduce the risk of nosocomial aspergillosis while in hospital-ideally in a positive pressure single room with high-efficiency particulate air filtration. However, neutral pressure rooms are a potential alternative, especially for patients requiring both protective and source isolation. This study examined mold and bacterial concentrations in air samples from positive and neutral pressure rooms to assess whether neutral pressure rooms offer a similar environment to that of positive pressure rooms in terms of mold concentrations in the air. Mold concentrations were found to be similar in the positive and neutral pressure room types examined in this study. These results add to the paucity of literature in this area.