Influence of building construction work on Aspergillus infection in a hospital setting

BACKGROUND AND OBJECTIVE: Aspergillus fumigatus is a major pathogen causing nosocomial infections. Hospital outbreaks of invasive aspergillosis have been associated with the renovation and construction of buildings. Building construction work for fire safety upgrading was undertaken during a16-week period in 2001 at Box Hill Hospital. This study was designed to examine the effect of construction on invasive aspergillosis when using standard and additional protective measures. METHODS: Baseline air sampling was conducted in 18 areas. The validity of the air sampling was assessed by comparing the ability of two air samplers to detect Aspergillus conidia. Surveillance of nosocomial Aspergillus infection was conducted by reviewing the records of patients with a sputum culture positive for Aspergillus and those prescribed amphotericin or itraconazole for the period of construction activity and the same period the previous year. RESULTS: Aspergillus was isolated infrequently and there was no statistically significant difference in the levels of viable pathogenic fungi between areas where construction work was undertaken and areas where it was not undertaken. A moderate agreement was observed between the two air samplers (kappa = 0.4; P < .05). There was no difference in the incidence of invasive aspergillosis between 2000 and 2001 (incidence density ratio, 1.2; 95% confidence interval, 0.3 to 4.1). CONCLUSION: The influence of construction work performed with protective measures needs to be examined in an environment with higher levels of airborne fungi to confirm the findings of this study.