Evaluation of the Results of a Periodic Environmental Biosecurity Assessment Program on Air Quality in Controlled Environment Rooms of Hospitals

Abstract

Aim: Determine the utility of the Periodic Environmental Biosecurity Assessment Program (PEBAP) in achieving clean air as measured by the number of colony-forming units (CFU) of fungi and bacteria in the air. Background: There is no international consensus on the sampling frequency, the recommended limits for microorganisms in the air nor on the usefulness of routine microbiological air monitoring of hospitals. Methods: During the PEBAP, data were recollected between 2010 and 2017 in eight hospitals in southeast Spain. Air samples were collected in very high risk rooms (VHRRs) and high risk rooms (HRRs), unoccupied, using active sampling methods. Temperature, relative humidity, air changes per hour (ACH), and differential pressure were measured. When limits of CFU of opportunistic fungi and bacteria established in the PEBAP were exceeded, corrective measures were adopted. Results: We found a reduction ( p < .01) of percentage of air samples with fungi growth throughout the years of PEBAP in all rooms. Aspergillus was the most frequent opportunistic fungus. We found a high compliance of the standards of CFU of bacteria in HRR, and the percentage of compliance in VHRR was lower than in HRR in all years. Differences in environmental and design parameters were statistically significant ( p < .05) between rooms, except for ACH. Conclusions: PEBAP resulted in a useful tool to maintain and improve air quality in hospitals. The control of environmental biosecurity requires a multidisciplinary approach from preventive medicine, engineering, and cleaning services. Aspergillus is the most frequent opportunistic fungus in southeast Spain.

Relationship Between Airborne Fungi Presence and the Position of the High Efficiency Particulate Air Filter in the Heating, Ventilation, and Air Conditioning System

“…In this study, the most frequently isolated fungi were nonopportunistic, but when opportunistic fungi were isolated, Aspergillus spp. was the most frequent (Sabuco-Tébar et al, 2022). This is in line with Caggiano et al (2014) who found that Aspergillus spp.…”

“…The high-efficiency filtration in HVAC systems reduces airborne infectious particles and prevents the spread of fungal spores (Dai et al, 2021; Hahn et al, 2002; Oren et al, 2001). The samples were recollected in a periodic environmental biosecurity assessment program for validation of controlled environment rooms; these programs are a useful tool that contribute to improving and maintaining indoor environmental conditions (Sabuco-Tébar et al, 2022). A limitation of retrospective studies is that they do not use measuring instruments designed to observe the event (Hernández-Avila et al, 2000).…”

“…This research was realized during a periodic environmental biosafety assessment program for validation of controlled environment rooms. These programs are an effective tool to improve air cleanliness (Faure et al, 2002; Pasquarella et al, 2012; Sabuco-Tébar et al, 2022), but the collection of samples by appointment represents a limitation for this study. In our study, the results show a greater number of ACH in the rooms with presence of fungi in the air with values of the median and the 75th percentile of ACH above the limits established in the Spanish standard.…”

“…In addition to the correct maintenance and validation of controlled environment rooms through periodic environmental biosecurity assessment programs, which are a useful tool to maintain and manage proper hospitals indoor air quality (Pasquarella et al, 2012; Sabuco-Tébar et al, 2022), it is essential to carry out a correct design of the facilities. Despite the recommendations in UNE 100713 (2005), we have found no studies on the influence of the terminal position of the HEPA filter in the HVAC system on the presence of airborne fungi in controlled environment rooms in hospitals.…”