Minimally invasive surgeries have spurred a growth in procedures, especially for patients with conditions that are difficult to treat, such as osteoarthritis. Joint replacement surgeries, for example, are quick and relatively low risk, but can make a world of difference for patients who undergo the procedures.

However, any patient that has a surgical procedure in a hospital risks infection from antibiotic-resistant bacteria, whose prevalence has been rising dramatically in recent years. And according to researchers from the University of Bath, antibiotic-resistant bacteria might be a problem even outside of the hospital.

Staphylococcus epidermidis is a common bacterium found on many peoples skin, and it is a relative of MRSA. In recent years, staph infections have become a problem as this usually harmless bacteria developed antibiotic-resistant mutations. Researchers took swabs from patients who suffered from staph infections after undergoing joint replacement or trauma fixation surgeries, and compared them to healthy volunteers. They were shocked to find that some of the healthy volunteers were harbouring deadly strains of the bacteria on their skin.

Joint replacement surgeries can make a positive difference in patients’ lives, but the prevalence of deadly strains of staph bacteria outside the hospital indicate that going under the knife might pose a greater threat than previously thought. Resistant infections are often fatal, and the bacteria’s presence outside a laboratory of hospital environment can give them an unfortunate evolutionary edge.

Researchers recommend that patients with deadly strains of staph already living on their skin be identified before surgery, and addressed before hygiene becomes a more deadly issue.