Technology That Defends Against Hospital-Acquired Infections

Can automated disinfection systems help reduce healthcare-associated infections?

In the news: Medicare cut payments to five Middle Tennessee hospitals because of failure to control healthcare-associated infections (HAIs) and prevent serious complications.

Gateway Medical Center, Saint Thomas Midtown Hospital, TriStar Hendersonville Medical Center, TriStar Southern Hills Medical Center and TriStar Stonecrest Medical Center were not alone in these cuts. In fact, 721 hospitals nationwide will see reduced Medicare payments for similar reasons.

This is one way the federal government is cracking down on formidable problems such as HAIs, and with good reason. The Centers for Disease Control and Prevention (CDC) estimates that one in 25 hospital patients (or more than 2 million people annually) acquires at least one HAI during their stay. And, when a patient contracts an infection, the CDC reports the average hospital costs add up to more than $15,000.

“The average hospital spends around $140,000 annually combating HAIs,” says Eric Bates, director of hospitality at Jewish Senior Living Center in Milwaukee.

Healthcare facilities that fail to ramp up their efforts to reduce these types of infections face stiff penalties — among them, a reduction in Medicare payments. As a result, hospital infection preventionists have renewed their interest in new technologies and programs designed to help keep infections at bay.

Ultraviolet-C (UV-C) technology, used to disinfect hospital operating rooms since the 1970s, is emerging as a preeminent means of disinfecting common areas and patient rooms in healthcare facilities. In fact, a healthcare business and policy news website recently predicted that the market for UV-C disinfection systems would grow from $30 million in 2014 to $80 million by 2017. But, the same source pointed out that as healthcare facilities add this equipment, questions remain, including how to deploy the systems most efficiently and, more importantly, whether the units do indeed reduce HAIs as promised.

Despite the unknowns, Bates proclaims he’s already a UV-C convert. Jewish Senior Living Center, he says, has seen a reduction in HAIs since adding the systems.

“We have already seen a significant drop in infections and estimate that this system will pay for itself within a year and a half,” he says. “When people say they really cannot afford to add this technology, I say, ‘They really cannot afford not to.’”

Germ Zappers

Portable room disinfection systems being eyed by environmental services professionals use Mercury vapor or Xenon lamps that produce ultraviolet light to destroy harmful bacteria, viruses, fungi and bacterial spores that might endanger patients. The systems are effective against common HAI-causing pathogens including Clostridium difficile, norovirus, influenza virus, Vancomycin-Resistant Enterococci and staph bacteria.

“UV-C systems kill any one-cell organism — and most super bugs are one-cell organisms,” says Alvin Arzaga, who as research assistant at Jewish Senior Living Center heads up the facility’s UV-C program and works with the University of Wisconsin-Milwaukee to study the technology’s effectiveness. 

There are three types of UV rays. UV-A is a long wave that passes through the ozone, while UV-B is a medium wave that is mostly absorbed by the ozone. This technology uses UV-C, which is completely absorbed by the Earth’s atmosphere. And because microorganisms on Earth are not exposed to UV-C naturally, they can not defend against it.

“That’s why this technology works to kill these organisms,” says Arzaga. “These systems can kill Ebola in 90 seconds.”

How they kill depends on which system is used: Mercury or Xenon. Mercury uses Photodimerization, which fuses the rungs of the DNA ladder to generate “typos” in the DNA, while Xenon systems add three additional processes. These include:
• Photohydration, which also damages the DNA rungs. The bases absorb water and change into a new molecule. 
• Photosplitting, which breaks the DNA backbone, similar to cutting a ribbon into pieces. 
• Photocrosslinking causes damage that prevents the cell from making new proteins, which are an important aspect of the cell wall. 

Whatever the technique, the energy produced by UV-C systems essentially passes through the cell walls of these microorganisms, where it is absorbed by DNA, RNA and proteins, and renders the cell unable to replicate. In other words, it’s no longer infectious.

That being said, Arzaga maintains Xenon has some inherent advantages over Mercury vapor systems. For example, Mercury is a toxic chemical element, so if a bulb breaks it can contaminate the area. Mercury also takes between 25 and 45 minutes to disinfect a standard patient room, while Xenon can complete a cycle in 5 to 10 minutes. Lastly, Mercury only attacks along a single spectrum, 253.7 nanometers, while Xenon’s germicidal spectrum goes from 200 to 280 nanometers.