Detection and analysis of airborne aerobes and Gram-negative bacteria and spread identification of airborne Escherichia coli using ERIC-PCR in hospital environment

This study was conducted to understand the enumeration and composition of airborne aerobes and Gram-negative bacteria and the spread of microbial aerosols in hospital environment. The aerobes and Gram-negative bacteria were identified and counted, and the similarity of Escherichia coli from different sites was analyzed by ERIC-PCR. The results showed that the enumerations of aerobes and inhalable aerobes in the corridor and hall were apparently higher than those in the three rooms (P<0.05). The airborne aerobes were mainly Staphylococcus and Escherichia. Gram-negative bacteria accounted for 40.08-46.98% of the total number. ERIC-PCR results of 44 E. coli isolates indicated that the similarity was between 56-100%. And 8 E. coli isolates from the three Rooms had more than 90% similarity with E. coli isolates from the corridor and hall. It could be concluded that the aerosols in the injection room can spread through air exchange. And thus effective measures should be taken to control and minimize the spread of microbial aerosols.