When a hospital patient checks out of a room, cleaning staff swoop in, disinfecting every item and surface to prevent the spread of infection.
The TV remote, bedframe, call button cord, trash can lid, closet handles, door knobs — nothing can be missed. Bed linens and privacy curtains are removed and double-bagged for laundering. Blinds and curtain rails are wiped down.
Still, dangerous infections spread.
If the previous occupant was infected with methicillin-resistant Staphylococcus aureus (MRSA), for example, the incoming patient has a 40% elevated risk of contracting the same infection — even when a hospital’s cleaning protocol exceeds infection-control standards.
“The danger extends far beyond the handful of patients who stay in that room, spreading from room to room to potentially affect the entire facility,” warn Cornell University researchers.
Hospital pathogens infect 1.4 million patients and cause 140,000 deaths each year in the United States and Europe alone. In the superbug era, with microbes like MRSA increasingly resistant to antibiotic treatment, the limits of surface cleaning are becoming more apparent — and more alarming.
“There is no easy way to clean a hospital or to keep it clean,” cautions Scottish microbiologist Stephanie Dancer, M.D., in a review of hospital surface cleaning strategies.
Hand hygiene among healthcare workers remains the critical line of defense against hospital-acquired infections. But the “Clean Hands Save Lives” message hasn’t worked, prompting a renewed interest in surface cleaning, among other strategies.
“The more contaminated the surface, the more likely healthcare workers and patients will pick up bacteria on their hands,” notes Ojan Assadian, M.D., president of the Austrian Society for Infection Control.
Why Hospital Surfaces Are So Hard to Clean
Infection outbreaks have been traced to all manner of contaminated surfaces: sinks, door handles, stethoscopes, glucometers, computer keyboards, telephone handles in the ICU.
Improvements in surface cleaning have successfully contained many of these outbreaks. A British hospital halted a MRSA crisis after doubling its cleaning schedule, from 60 to 120 hours per week. When a Minnesota hospital introduced bleach wipes, incidence of C. difficile infection dropped from 31 patients a year to 4.
But all too often, surface cleaning falls short.
For instance, in a study of 23 American hospitals, over 50% of surfaces in patient rooms were missed completely after patients were discharged. Cleaning rates fell below 30% for toilet handles, bedpan cleaners, light switches, and door knobs.
Blood pressure cuffs, ultrasound machines, ECG leads, ventilators — medical devices get the short shrift, too. Just a few spores of Clostridium difficile can transmit infection in a vulnerable patient, and yet, as one study notes, “It is likely that numerous items of clinical equipment receive only sporadic cleaning attention or, perhaps, none at all.”
How can that be?
For starters, hospitals are overcrowded and crews are overworked.
“In an era of cost-cutting, those with cleaning responsibilities cannot hope to decontaminate all high-risk surfaces as often as required,” asserts Dr. Dancer.
Stethoscopes, for example, are a common source of contamination and are easily disinfected with alcohol. But, research suggests, “even this simple procedure is abandoned, ignored, or forgotten when staff are overworked.”
What’s more, cleaning crews, especially those outsourced to private companies, may be poorly trained, poorly managed, or both.
Cleaning staff may not know which products can be used for which surfaces, how long a wipe should be used before disposal, or even the distinctions between “cleaning,” “sanitizing,” and “disinfecting.” At some hospitals, housekeeping staff clean bed spaces and rooms whereas custodians disinfect equipment and beds, a division of labour that creates confusion.
Since many cleaning flaws stem from human error, hospitals have begun using automated cleaning. But these systems, especially those involving hydrogen peroxide or UV light, can be expensive and time consuming to operate. Some involve toxic products that can’t be used near patients.
Still, human error is only part of the problem. Cleaning materials themselves can spread infectious microbes.
Some microfiber cleaning cloths “merely distribute organisms across surfaces instead of removing them,” research has found. Likewise, water used for mop rinsing can become contaminated and spread pathogens around the hospital.
Another roadblock to optimal cleaning: hospitals can’t accurately gauge whether a room or particular surface has been disinfected because most cleaned areas are visually inspected. As a British study demonstrated, an inspector can’t look at a door handle or toilet flush and know, with scientific certainty, whether it’s free of pathogens.
“A surface can look clean but be heavily contaminated,” says Prof. Assadian. “Or, you can have a dirty looking surface with no relevant pathogenic bacteria.”
But let’s say all the above problems were solved — that every surface in every hospital was always cleaned to the highest standards by well trained, well-managed staff. Would that stop lethal microbes from being spread via surfaces?
No! Because hospitals face another reality: pathogens come right back.
At a South Carolina hospital, 36 bed rails were sampled for bacteria just before cleaning and then checked at four intervals afterwards. Within three hours, the bacterial burdens had rebounded to unsafe levels.
“Our study suggests that cleaning approximately every 2 hours would be necessary to maintain the population of this pathogen at the proposed non-detectable level,” the researchers concluded.
This is no small finding, as bed rails are the most contaminated surfaces in a hospital room, and dangerous microbes are easily transferred from bed rails to healthcare workers’ hands.
In fact, a Chicago study found VRE bacteria were transferred to gloved hands nearly half of the time after contact with bed rails, and 46% of handprint cultures grew VRE after just 5 seconds of contact with the bed rail.
Not only can pathogens rebound and spread quickly, but some never disappear.
VRE, Dr. Dancer notes, “seems to be particularly adept at withstanding repeated attempts at disinfection, including double bleach-based cleaning.”
Acinetobacter baumannii is hardy, too. Even after extreme cleaning measures were taken to clean rooms contaminated by this bacteria, half the rooms still harboured the organism.
The Future: Cleaning the Air
As cleaning technology improves, so will the effectiveness of surface disinfection. However, just as hand hygiene will never suffice to halt the spread of MRSA, VRE, and the rest, neither will surface cleaning.
Which means hospitals require a third line of defence to fight the superbug crisis: air disinfection.
“You can target the surface itself, which is difficult and time-consuming,” Prof. Assadian notes, “or you can attack the vector that causes contamination of these surfaces.”
In other words, the air.
When an infected patient vomits, coughs, sneezes, talks or even breathes, pathogens can be launched airborne. From there, particles can traverse the hospital via air currents and settle on any surface — a doctor’s lab coat, an IV pole, a stretcher, a supply cart, a computer keyboard a mattress.
A single infected patient walking to a hallway bathroom can pose a major threat.
It is therefore critical for hospitals to inactivate these dangerous particles before they settle on surfaces and are transmitted to patients. By far the most effective method of air disinfection is low-temperature plasma technology, increasingly used in European hospitals.
Plasma technology cleans air 24 hours a day and does not rely, in any way, on human training or management.
Clean hands do save lives, and so do clean surfaces. But unless the air is clean, too, the go-to prevention methods will not stop the pathogens from wreaking havoc at hospitals around the globe.