Bacterial bioaerosols determination in nurse stations in a governmental hospital in Tehran

Bacterial exposure in hospitals due to the presence of pathogens in hospitals is one of important health problems for medical staff. The World Health Organization (WHO) reported a global outbreak of hospital infections from 5.7% to 19.1% in the 2011 report. The aim of this study was to identify bacterial bioaerosols in nursing stations in a public hospital in Tehran to determine the occupational hazards of them.

This cross-sectional study was conducted three times at fifteen nursing station in 15 different departments of a public hospital in Tehran. 45 samples were prepared on three culture media including Mackangi Agar, nutrient agar and Manitol Salt Agar. Air samples were prepared according to NIOSH 0800 method by a bacterial sampler with a flow rate of 28.3 L/min for 5 min. Samples were analyzed by microbial screening test.

Mean of the bacterial infection was 180.03±125.27 CFU/m3. The results showed that there were gram positive staphylococcus aureus in the all air samples of nursing stations. Moreover, in 26.7% of occupational exposure nursing stations with Acinetobacter Iwoffii was observed as the most common gram negative bacteria.. Maximum bacterial number was found in orthopedic nursing station (399.99 CFU/m3) and heart transplant nursing station had the minimum bacterial infection (43.73 CFU/m3).

Eighty percent of occupational exposure in the samples had higher exposure to bacterial pathogens than the standards set by ACGIH (75 CFU/m3). Due to the presence of Staphylococcus aureus, E. coli and Acinetobacter Iwoffii in nursing stations, there was a risk of hospital infections in health care workers. It seems unsuitable surface sterilization and lake of useful engineered controlling methods has led to bio aerosol scattering in the air of studied stations