High-risk Staphylococcus aureus transmission in the operating room: A call for widespread improvements in perioperative hand hygiene and patient decolonization practices.

BACKGROUND

Increased awareness of the epidemiology of transmission of pathogenic bacterial strain characteristics may help to improve compliance with intraoperative infection control measures. Our aim was to characterize the epidemiology of intraoperative transmission of high-risk Staphylococcus aureus sequence types (STs).

METHODS

S aureus isolates collected from 3 academic medical centers underwent whole cell genome analysis, analytical profile indexing, and biofilm absorbance. Transmission dynamics for hypertransmissible, strong biofilm-forming, antibiotic-resistant, and virulent STs were assessed.

RESULTS

S aureus ST 5 was associated with increased risk of transmission (adjusted incidence risk ratio, 6.67; 95% confidence interval [CI], 1.82-24.41; P = .0008), greater biofilm absorbance (ST 5 median absorbance ± SD, 3.08 ± 0.642 vs other ST median absorbance ± SD, 2.38 ± 1.01; corrected P = .021), multidrug resistance (odds ratio, 7.82; 95% CI, 2.19-27.95; P = .002), and infection (6/38 ST 5 vs 6/140 STs; relative risk, 3.68; 95% CI, 1.26-10.78; P = .022). Provider hands (n = 3) and patients (n = 4) were confirmed sources of ST 5 transmission. Transmission locations included provider hands (n = 3), patient skin sites (n = 4), and environmental surfaces (n = 2). All observed transmission stories involved the within-case mode of transmission. Two of the ST 5 transmission events were directly linked to infection.

CONCLUSIONS

Intraoperative S aureus ST 5 isolates are hypertransmissible and pathogenic. Improved compliance with hand hygiene and patient decolonization may help to control the spread of these dangerous pathogens.