Engineering Infection Controls to Reduce Indoor Transmission of Respiratory Infections

Researchers at the University of Colorado conducted a comprehensive scoping review of 672 studies on engineering infection control interventions to reduce the spread of respiratory infections transmitted through indoor air. The study, funded by the National Institute for Occupational Safety and Health at the Centers for Disease Control and Prevention, aimed to identify and describe primary studies evaluating the effects of such interventions. The researchers analyzed studies published between 1929 and 2024 and found significant heterogeneity in the available evidence, highlighting the need for refinements in classification of interventions and outcomes to strengthen reporting of these evaluations.

Key Takeaways:

• The study identified 672 studies on engineering infection control interventions published between 1929 and 2024, with most (n = 606) evaluating environmental samples only.
• Approximately half of the studies (n = 405) included at least 1 intervention classified as pathogen inactivation, while fewer involved pathogen removal (n = 200) or air exchange or dilution (n = 143).
• The study found that harms, such as toxic byproducts, were rarely measured in the studies, and there was a gap in evidence for studies measuring efficacy outcomes highly relevant for human infection transmission or harms.
• Significant heterogeneity in the available evidence was identified, highlighting the need for refinements in classification of interventions and outcomes to strengthen reporting of these evaluations.
• The study emphasized the importance of improving reporting of interventions and outcomes, including the use of standardized classification systems.

Statistics:

• 672 studies on engineering infection control interventions were identified, with publication dates ranging from 1929 to 2024.
• 606 studies (90%) evaluated environmental samples only, while 57 studies included human participants and 9 included sentinel animal subjects.
• 405 studies (60%) included at least 1 intervention classified as pathogen inactivation.
• 332 studies (70%) measured the quantity of viable nonpathogenic organisms from air samples.

Sources:

• National Institute for Occupational Safety and Health at the Centers for Disease Control and Prevention
• University of Colorado
• Medline, Embase, Global Health, Cochrane Central Register of Controlled Trials, CINAHL, Scopus, and Environmental Science Collection
• Annals of Internal Medicine
• NewsRx