The Use of antibacterial or antimicrobial coatings on medical curtains
Antibacterial medical curtains – overview
To mitigate the problem of cross-contamination, manufacturers of hospital curtains will often include an antimicrobial coating on the curtain’s surface. This coating can take many forms, such as layers of germicidal chemicals, or can incorporate elements that can inferior the biological functions of microbes, such as silver or zinc ions. The coating can be applied after the curtain manufacturing process, or it can be impregnated into the material of the curtain.
Manufacturers offering antimicrobial coatings claim that they kill or disrupt microbes on contact, lengthening the time they can go between cleanings or replacements. This process also works on lowering the risk of cross-contamination when the patient privacy curtain is in situ.
Are antibacterial curtains effective at killing bacteria?
It is helpful to be cautious about these claims, evaluating them with a practical, real-world outlook concerning infection control.
To offer an example, consider a patient that coughs vigorously. When that happens, a thick piece of viscous sputum sticks to a medical curtain impregnated with silver ions. While the part of the sputum immediately touching the silver-impregnated curtain may be subject to the effects of the antimicrobial coating, the rest is not. The sputum is unaffected in this area and is ready to cross-contaminate patients and staff, who can unwittingly spread pathogens even further.
No matter how effective an antimicrobial coating is, it cannot be as effective as the physical removal of contaminants from a hard surface that can be repeatedly cleaned with antimicrobial products.
Do antibacterial hospital curtains need to be changed less frequently?
Many studies have been carried out over the past 20 years showing that curtains are frequently and rapidly contaminated and are a source of pathogens including MRSA and VRE. Whilst there is no guarantee that a curtain does not become contaminated immediately, a 2012 study in the American Journal of Infection Control showed that 92% of curtains were contaminated within a week and 95% within 3 weeks.
The question therefore is does an antibacterial coating extend the average period before a curtain becomes contaminated.
A 4-week study published by Cambridge University Press in 2015 addressed exactly this question and found that the median time to first contamination was 14 days for antimicrobial curtains compared to 2 days for standard curtains. The study also found that, after 14 days, the level of contamination was not significantly different in the antimicrobial curtains compared to the standard curtains.
In conclusion, whilst there is an improved reduction in infection in the short term, antimicrobial surfaces provide no significant benefit in the longer term. The length of this period of benefit will be determined by other factors such as the specific infection control regimes and the general presence of pathogens in the surrounding area.
Can antibacterial curtains lead to a false sense of security?
Overworked staff may have a false sense of security with regards to the antimicrobial properties of the curtain and may not inspect it thoroughly or replace it frequently enough. Curtains are commonplace in our homes, and people are used to simply grabbing any part of the curtain to open or close it. This means that any part of the curtain may have been touched, and cleaning staff must inspect the entire curtain for signs of contamination.
The risks associated with the overuse of antibacterial coatings.
Medical science is fighting an ongoing battle with pathogens. Scientists continually need to develop new strains of antibiotics and to create new antivirals and vaccines. Part of medical strategy in this ongoing battle is to minimise opportunities for pathogens to evolve defences. However the commonplace use of antibacterial surfaces in hospitals may risk creating a breeding ground for new types of antimicrobial resistance.
The Journal of Hospital Infection published a research review in 2020 that examined this risk. The review found studies that indicated risks associated with resistance on antimicrobial surfaces, either from novel mutations or by species-sorting, which is the process by which only inherently resistant species survive and flourish on the antimicrobial surface. Furthermore, most studies that look at this problem take place in labs and don’t study the risk of breeding resistant bacteria in a clinical setting, where there are far more variable factors at play than in the controlled environment of a scientific study.
Unfortunately, a medical privacy curtain with antimicrobial properties is an ideal environment for pathogens that are resistant to the coating to evolve and flourish. The use of these coatings should be rationed to essential settings, such as a surgical theatre. They should not be used on curtains when each one risks developing resistant microbes that could spread.