Roles of sunlight and natural ventilation for controlling infection: historical and current perspectives.

BACKGROUND: Infections caught in buildings are a major global cause of sickness and mortality. Understanding how infections spread is pivotal to public health yet current knowledge of indoor transmission remains poor. AIM: To review the roles of natural ventilation and sunlight for controlling infection within healthcare environments. METHODS: Comprehensive literature search was performed, using electronic and library databases to retrieve English language papers combining infection; risk; pathogen; and mention of ventilation; fresh air; and sunlight. Foreign language articles with English translation were included, with no limit imposed on publication date. FINDINGS: In the past, hospitals were designed with south-facing glazing, cross-ventilation and high ceilings because fresh air and sunlight were thought to reduce infection risk. Historical and recent studies suggest that natural ventilation offers protection from transmission of airborne pathogens. Particle size, dispersal characteristics and transmission risk require more work to justify infection control practices concerning airborne pathogens. Sunlight boosts resistance to infection, with older studies suggesting potential roles for surface decontamination. CONCLUSIONS: Current knowledge of indoor transmission of pathogens is inadequate, partly due to lack of agreed definitions for particle types and mechanisms of spread. There is recent evidence to support historical data on the effects of natural ventilation but virtually none for sunlight. Modern practice of designing healthcare buildings for comfort favours pathogen persistence. As the number of effective antimicrobial agents declines, further work is required to clarify absolute risks from airborne pathogens along with any potential benefits from additional fresh air and sunlight.

Dietary intervention in chronic fatigue syndrome.

BACKGROUND: Anecdotal reports and books have been published linking an over growth of Candida Albicans with chronic fatigue syndrome (CFS), suggesting dietary change as a treatment option. Little scientific data has been published to validate this controversial theory. This study aims to determine the efficacy of dietary intervention on level of fatigue and quality of life (QoL) in individuals with CFS. METHODS: A 24-week randomized intervention study was conducted with 52 individuals diagnosed with CFS. Patients were randomized to either a low sugar low yeast (LSLY) or healthy eating (HE) dietary interventions. Primary outcome measures were fatigue as measured by the Chalder Fatigue Score and QoL measured by Medical Outcomes Survey Short Form-36. RESULTS: A high drop out rate occurred with 13 participants not completing the final evaluation (7HE/6LSLY). Intention to treat analysis showed no statistically significant differences on primary outcome measurements. CONCLUSION: In this randomized control trial, a LSLY diet appeared to be no more efficacious on levels of fatigue or QoL compared to HE. Given the difficulty with dietary compliance experienced by participants, especially in the LSLY group, it would appear HE guidance is a more pragmatic approach than advocating a complicated dietary regime.