Friday, 19 April, 2024
HomeHospital MedicineHospital infections: 2-year ICU study again makes the case for copper

Hospital infections: 2-year ICU study again makes the case for copper

There are some 90,ooo infection related deaths in US hospitals each year. A growing chorus of researchers argue that replacing stainless steel surfaces with copper is the solution.

Keeping patients from getting sick during an inpatient stay has long been a problem for hospitals – and, STAT News reports, it’s an issue that has grown all the more pressing during a pandemic. Even before the rise of COVID-19, hospitals have increasingly struggled to get health-care associated infections in check. There are 2m such infections – and 90,000 related deaths – in US hospitals every year.

The report says as hunt for ways to reduce the spread of pathogens to patients, a growing chorus of researchers is arguing that a simple swap might help: replace stainless steel surfaces with copper. “Copper is the fastest thing that can kill anything,” said Michael Schmidt, a professor of microbiology and immunology at the Medical University of South Carolina and a leading researcher on antimicrobial copper.

Copper’s ability to neutralise microbes is well-known. Researchers studying SARS-CoV-2, the disease that causes COVID-19 found that the virus lasts for several days on stainless steel – which most hospitals use for the majority of surfaces – but dies within hours of landing on copper.

STAT News reports that despite the evidence on copper’s ability to bust up bacteria, many hospital leaders remain unconvinced. They argue it’s still not clear whether reducing the amount of a pathogen in a particular area of a hospital actually translates to a lower risk of infection. “In infection prevention, we’re a pretty pragmatic bunch. We want to know that something is effective,” said Graham Snyder, medical director of infection prevention at UPMC (Pittsburgh). “There’s no doubt about it: Organisms are less likely to survive on an antimicrobial surface. Is that less likely to reduce infections? That’s very hard to prove.”

Schmidt and other researchers studying copper are hopeful that a growing body of research will help make the case for copper. In 2007, he began a study inside eight intensive care unit rooms at three US hospitals where copper was installed on different objects: bedrails, overbed tray tables, intravenous poles, and armrests of visitors’ chairs, as well as on surfaces like nurses’ call buttons. Over six years, Schmidt found that infections in these rooms dropped 58% compared to eight unmodified ICU rooms. He also found significantly lower rates of VRE and MRSA bacteria, notorious for causing inpatient infections, in the copper rooms.

And last fall, Schmidt published his latest research, a nearly two-year study that showed that copper beds inside the ICU of a hospital in Indiana harboured an average of 95% fewer bacteria. (That study was supported by an “unrestricted research grant” from Bed Techs, which retrofits hospital beds with copper. Schmidt’s work has largely been funded by the Department of Defence, but he has also received support from a copper industry group to study the metal in non-patient-care settings.)

Researchers who study copper say its power lies in how it attacks a pathogen. In the presence of bacteria like E. coli, copper releases reactive ions that punch holes in the cell membrane, invade, and then shred the DNA and proteins within. Sometimes copper metal is even more, well, metal. Unlike gold or silver, copper contains a free electron in its outer orbital shell, which interacts with oxygen in the air – resulting in an energised form of oxygen, a molecular grenade of sorts that blasts through viral envelopes and blows up the germ-replicating instructions on the inside.

Hospitals have a clear incentive to curb the spread of pathogens. The average single-bed hospital room in the US sees between four or five infections annually, and the cost, in terms of money wasted and lives lost, is high. For every one person who contracts an infection while in the hospital, their stays are estimated to be as much as 19 days longer, as well as about $43,000 more expensive.

While there is a correlation between installing copper and reducing the burden of bacteria, there is no proven causation between the presence of copper and the decrease in the number of patient infections a hospital sees — an outcome that some hospital leaders said they would like to see before making the switch.

There’s also the equally pragmatic matter of the overall cost of installing copper, which is far more expensive than plastic or stainless steel. For hospitals, which generally run on small operating margins, it’s more worthwhile to put extra money into patient care, including existing resources intended to keep people safe.

“It’s a zero-sum game. We don’t have the resources to do everything,” said David Weber, who, as medical director of epidemiology at UNC Health Care in North Carolina, works to help prevent health care-associated infections.

And as it currently stands, many hospitals already have easy-to-clean surfaces. I don’t need an antimicrobial surface to make sure bedrails aren’t a route of transmission,” Snyder said. “I might decide a better investment is making sure my environmental services team does a good job at cleaning.”

Some hospital leaders also said they’re not convinced that copper’s effectiveness will readily translate to the general hospital environment, given that most studies have been in the ICU.

“The health care community wants to know if this will work in all hospital rooms, and, candidly, we don’t know,” Schmidt said. “That’s one of the principal reasons hospitals are saying they’re reluctant to adopt.”

Still, Schmidt said the results gathered from studies in the ICU suggest that a hospital, on the whole, is likely to see a decrease in health care-associated infections with copper surfaces.

“The mission was to ask a simple question: Could I reduce the incidents of health care-associated infections? My answer was yes,” he said. “And I thought the market would take that observation and run with it.”

Abstract
Microbial burden associated with near-patient touch surfaces results in a greater risk of health care-associated infections (HAIs). Acute care beds may be a critical fomite, as traditional plastic surfaces harbor the highest concentrations of bacteria associated with high-touch surfaces in a hospital room’s patient zone. Five high-touch intensive care unit (ICU) bed surfaces encountered by patients, health care workers, and visitors were monitored by routine culture to assess the effect U.S. Environmental Protection Agency (U.S. EPA)-registered antimicrobial copper materials have on the microbial burden. Despite both daily and discharge cleaning and disinfection, each control bed’s plastic surfaces exceeded bacterial concentrations recommended subsequent to terminal cleaning and disinfection (TC&D) of 2.5 aerobic CFU/cm2. Beds with self-disinfecting (copper) surfaces harbored significantly fewer bacteria throughout the patient stay than control beds, at levels below those considered to increase the likelihood of HAIs. With adherence to routine daily and terminal cleaning regimes throughout the study, the copper alloy surfaces neither tarnished nor required additional cleaning or special maintenance. Beds encapsulated with US. EPA-registered antimicrobial copper materials were found to sustain the microbial burden below the TC&D risk threshold levels throughout the patient stay, suggesting that outfitting acute care beds with such materials may be an important supplement to controlling the concentration of infectious agents and thereby potentially reducing the overall HAI risk.

Authors
Michael G Schmidt, Hubert H Attaway, Sarah E Fairey, Jayna Howard, Denise Mohr, Stephanie Craig

 

[link url="https://www.statnews.com/2020/09/24/as-hospitals-look-to-prevent-infections-a-chorus-of-researchers-make-a-case-for-copper-surfaces/?utm_source=STAT+Newsletters&utm_campaign=b27a856f4d-Daily_Recap&utm_medium=email&utm_term=0_8cab1d7961-b27a856f4d-152512097"]STAT News material[/link]

 

[link url="https://aem.asm.org/content/86/1/e01886-19#sec-6"]Applied and Environmental Biology abstract[/link]

MedicalBrief — our free weekly e-newsletter

We'd appreciate as much information as possible, however only an email address is required.