[Antibiotic resistance gene contamination status in air conditioning filter dust of a hospital in Wuhan City].

OBJECTIVE

To understand the differences in the types and levels of antibiotic resistance genes contamination in the dust of air conditioning filters in hospital inpatient wards.

METHODS

Wet cotton swabs were used to collect dust samples from air conditioning filters in 19 wards of 7 departments of a third-grade general hospital in Wuhan. The 24 antibiotic resistance genes related to 6 major antibiotics were qualitatively detected by PCR, and 6 typical resistance genes were detected by real-time PCR.

RESULTS

Sulfonamides(sulI, sulII), β-lactams(mecA, blaOXA-51, blaTEM, blaCTX-M, blaSHV, blaKPC, blaNDM-1, blaIMP, blaVIM), aminoglycosides(aac(6᾿-aph(2᾿, aacC2), macrolides(ermA, ermC, ereA), quinolones(qnrA, qnrB, qnrS), a total of five categories of 19 antibiotic resistance genes were detected in the dust of the filter. These include four carbapenem resistance genes(blaNDM-1, blaIMP, blaVIM, blaKPC). The average of absolute content(copies/g) of the six typical resistance genes from high to low was: sulI(1. 06×10~9)>sulII(1. 78×10~8)>blaNDM-1(3. 97×10~7)>aac(6᾿-aph(2᾿(3. 20×10~7)>blaTEM(1. 03×10~7)>aacC2(1. 13×10~6). Among the seven tested departments, traumatic surgery detected up to 18 resistant gene species and 6 typical genes with the highest absolute content. The absolute content of six typical genes in ICU and surgical wards was higher than medical wards.

CONCLUSION

A variety of antibiotic resistance genes are detected in the dust of some hospital ward air conditioning filters, suggesting that there may be current or past pollution of resistant bacteria in the relevant environment.