A heightened awareness of the dangers of cross-contamination in the healthcare environment is prompting environmental services (ES) professionals and infection control practitioners (ICPs) to pay closer attention to the way antibacterial wipes are being used in facilities. A new study coming out of the United Kingdom about the ability of wipes to spread bacteria is garnering attention as well.
The study, conducted by a team of researchers at the Welsh School of Pharmacy at Cardiff University in Wales, revealed that antimicrobial wipes used to clean and disinfect environmental surfaces in hospitals can contribute to the spread of pathogenic microorganisms after their first use. The study examined the ability of antimicrobial wipes to kill and remove bacteria from surfaces and to prevent the spread of healthcare-acquired infections (HAIs). The researchers found that current protocols utilized by hospital staff have the potential to spread pathogens after only the first use of a wipe.
The team, led by Jean-Yves Maillard, BSc, PhD, senior lecturer in pharmaceutical microbiology at the Welsh School of Pharmacy at Cardiff University, is now calling for a “one wipe, one application per surface” approach to infection prevention and control in healthcare environments.
“The use of wipes is a relatively new addition to the measures available for infection control,” Maillard says. “Wipes are easy and rapid to use. In addition some wipes are good at removing a microbial bioburden dried on a surface. By reducing microbial contaminant from a surface, notably a surface proximal to the patient (e.g., a bed rail), then the risk of transferring microorganisms to the patient or the healthcare worker (HCW) will be reduced. However, like all control measure, wipes have to be used appropriately. One of the risks associated with the use of wipes is the transfer of microorganisms to other surfaces. If wipes are use only once on one surface, then the risk of transferring microorganisms removed from a surface would be low.”
The Cardiff University research involved a surveillance program observing hospital staff using surface wipes to decontaminate surfaces commonly touched by HCWs and patients, such as monitors, bed rails, tables and key pads. It was found that the wipes were being applied to the same surface several times and used on consecutive surfaces before being discarded. These actions were then replicated in the lab alongside a three-step system, developed by the research team to test the ability of several commercially available wipes to disinfect surfaces contaminated with strains Staphylococcus aureus, including MRSA and MSSA. The system tested the removal of pathogens, the transmission of them, and the anti-microbial properties of wipes. The study revealed that although some wipes can remove higher numbers of bacteria from surfaces than others, the wipes tested were unable to kill the bacteria removed. As a result, high numbers of bacteria were transferred to other surfaces when reused.
Gareth Williams, PhD, a microbiologist at the Welsh School of Pharmacy, notes, “Our surveillance study in its own right has been highly revealing in that it has highlighted the risks associated with the way decontamination products are currently being deployed in Welsh hospitals and the need for routine observation as well as proper training in the use of these wipes in reducing risks of infection to patients. On the whole, wipes can be effective in removing, killing and preventing the transfer of pathogens such as MRSA but only if used in the right way. We found that the most effective way is to prevent the risk of MRSA spread in hospital wards is to ensure the wipe is used only once on one surface.”
Maillard says the study is not a condemnation of antibacterial wipes, which remain an effective and easy way to decontaminate surfaces. “Decreasing microbial bioburden on surfaces is important and should contribute to a decrease in infection. One of the problems is the many different types and shapes of surfaces to clean. With this in mind, wipes are easy to use on any type and shape of surfaces and this is an advantage.”
When comparing wipes with germicides that are sprayed onto cloths and then applied to surfaces, Maillard says, “The use of a spray-on and cloth might be associated with some problems, as one might aerosolize and spread microorganisms widely on surfaces. We have just finished another study to compare the efficacy of an alcohol-impregnated wipe and a wipe onto which an alcohol is sprayed before used. By all accounts, the impregnated wipe was much better. So, it seems that impregnated wipes, if used appropriately, might contribute better to decreasing microbial bioburden from surfaces.”
“To achieve effective contact time, the surface area needs to remain wet for the appropriate contact time,” emphasizes Tiffany Liss, marketing manager for Safetec of America, Inc. “A wipe that contains high amounts of alcohol dries and evaporates too quickly then doesn’t hold the effective kill time needed. You would then have to use several wipes to keep the surface wet to achieve the kill claims needed. Depending on the product, some products even after the alcohol has evaporated still leave an agent that is effective against the same microbes.” Liss adds, “Clinicians need to use only one wipe per one surface as shown by the Cardiff study; they need to use the disinfectant wipe one time then discard. The best rule to abide by when using a disinfecting wipe is: time/bactericide application + wait time + time + kill agent = reduction in microbes.”
A number of studies point to the longevity of pathogens on inanimate surfaces (Kramer, Schwebke and Kampf, 2006), but Maillard makes one distinction, “I don’t think there is an increased persistence of microorganisms on surfaces, but that we are able to measure more accurately the longevity of pathogens on surfaces. Research in this field is essential and highlights the need to control microbial contamination on surfaces. It has been well documented that surfaces, notably those proximal to patients, are involved in the spread of infection.”
“Clinicians and environmental services personnel need to be constantly reminded that patient-care equipment and medical devices as well as environmental surfaces can serve as reservoirs for pathogenic microorganisms,” says Jean Fleming, RN, MPM, CIC, clinical director infection prevention and education for Professional Disposables International, Inc. “Today we are a consumer-driven society and healthcare facilities serve the consumer. The public is very much aware about disease transmission, especially with increasing media reports of infection transmission within healthcare environments. The consumer, along with expectations from healthcare regulatory agencies, is looking at the environment. Therefore, creating and maintaining a safe care environment is critical. Pathogenic microorganisms may survive from hours to days to weeks if proper cleaning and disinfection is not performed.”
Valerie Williamson, a category manager for Kimberly-Clark Professional, says it is essential that HCWs understand the factors impacting the number and types of microorganisms present on environmental surfaces, including number of people in the environment, amount of activity, amount of moisture (though microorganisms are present in great numbers in moist organic environments, some can also persist under dry conditions), presence of material capable of supporting microbial growth, the rate at which organisms suspended in air are removed, and the type of surface and its orientation (horizontal vs. vertical).
“Health experts are looking at contaminated surfaces in healthcare facilities as a possible mode of transmission for multiple drug-resistant bacteria,” Williamson explains. “Common germs like Staph can live up to three weeks on a dry surface. Vancomycin-resistant enterococci (VRE) can live up to four months. Clostridium difficile is another hardy germ that can survive in the hospital environment. The CDC is clear in its recommendations that cleaning and disinfecting environmental surfaces in healthcare facilities is critical to reducing the contribution of those surfaces to the incidence of healthcare-associated infections. In addition to proper hand hygiene, cleaning and disinfecting can help to minimize the transfer of microorganisms that can occur via hand contact between contaminated surfaces and patients.”
Fleming adds, “Too often healthcare personnel do not recognize that some frequently touched surfaces in the environment and patient care equipment are sources for transmission. Ongoing education and monitoring of practices must be conducted by infection preventionists which may include infection control professionals and department management. As part of this activity it is important to identify the frequently touched items and surfaces that are at a greater risk for cross-contamination and set proper cleaning and disinfection protocols. Disinfection of surfaces and items may not just be the responsibility of the environmental services department. Patient-care items and some clinical department-specific surfaces may be the responsibility of the clinical department staff. Therefore protocols and procedures should outline who is responsible for cleaning/disinfection, the frequency for performing tasks and what product to use for disinfection.”
It is up to ES professionals and HCWs to diligently clean environmental surfaces. Maillard says he suspects not all hospital staff understand how to this. “Observations of the use of wipes by HCWs in two different hospitals highlighted the fact that the same wipe was reused on different surfaces,” he says. “These observations enabled us to test accurately the risk of microbial transfer to surfaces and to emphasis the risk of spreading microorganisms rather than removing them. I would say that this is the main risk associated with the use of wipes.”
Careful selection of cleaning and disinfection tools can have a significant impact on the efficacy of the decontamination process, Williamson says. “According to research, the wiping material used can dramatically affect the amount of disinfecting agent that actually reaches the surface being cleaned,” she says. “For example, research has shown that when cotton rags and cellulose wipers (paper towels) are used with an open bucket of disinfecting solution (bleach or quaternary amines), the amount of active disinfecting agents actually reaching the surface to be cleaned can be as much as 53 percent less than the amount of actives in the original disinfectant solution. However, the research also showed that when a wiper is used that is specifically designed to be compatible with disinfecting/sanitizing chemicals like quats and bleach, and is contained in a closed-bucket system in which individual wipers are removed from a port in the top, a vastly higher percentage of chemicals are reaching the surface. The closed bucket system, combined with the disposable nature of the wipes, addresses CDC concerns that cleaning cloths can be a source of contamination, especially if left soaking in dirty cleaning solutions.”
Williamson continues, “APIC calls for the use of disposable cleaning cloths during environmental cleaning as a way to prevent and/or control multiple drug-resistant bacteria and notes that, for all environmental surface cleaning, cloths should be thoroughly moistened with disinfectant. APIC further cautions against returning a cloth to the bucket of disinfectant once it has been used to wipe surfaces as this may ‘promote increased environmental contamination and microbial spread.’”
“One way to address cross-contamination and eliminate reservoirs for transmission is to perform environmental rounds to ensure that cleaning/disinfection protocols are being followed,” Fleming suggests. “Nothing beats visual inspection and observing practices. These monitoring activities does not have to fall entirely on the shoulders of busy infection prevention and control professionals, but can be performed by clinical department and environmental services management and the HCWs themselves. Forming environmental teams made up of clinical and housekeeping staff to observe practices and provide feedback to their peers is another way to address cross-contamination and eliminate reservoirs. The team approach to improving practices by involving all levels of staff and not just management staff will contribute to better satisfaction and acceptance by workers. The team can also be involved in education and training of new and old employees about proper cleaning and disinfection practices and the rationale as to why it is important to maintain a safe environment for patients, visitors and co- workers.”
Fleming continues, “Additionally, a big challenge to healthcare facilities is identifying who is responsible for cleaning and disinfecting surfaces and items. It is essential that responsibility be reinforced. Too often clinicians feel that “it is not my job” or they are not aware as to who is responsible. In order to reduce cross-contamination and eliminating reservoirs for pathogens, it is important to have disinfectant products accessible for staff to use. Pre-moistened germicidal wipes that are placed at the point of use is not only convenient for staff, but also will ensure compliance with protocols. If staff members do not have product at the point of use or need, surfaces or items are not going to be cleaned and disinfected as often as they should."
It is essential for HCWs to realize that there is a point at which wipes become ineffective, and that they must follow the manufacturers’ recommendations for proper contact time for surface wipes and when to use a new wipe.
“The antimicrobials contained within a wipe are usually at a low concentration and their antimicrobial effect will be limited,” Maillard says. “We demonstrated that when the number of bacteria on a surface is high, the wipes were unable to kill all the microorganisms removed from the surface.”
Fleming points out that the Cardiff study was a European study using a grapefruit extract-containing test wipe and unmedicated control wipes. “It is important to note that in the U.S., per CDC guidelines and OSHA regulations, healthcare facilities must use Environmental Protection Agency (EPA)-registered hospital disinfectants,” she emphasizes. “To receive EPA-registration, manufacturers must prove efficacy ‘kill’ claims against significant microorganisms and each claim is reviewed and validated by the EPA. Kill claims is defined when a disinfectant product is tested to have 100 percent efficacy against a specific organism at a determined contact time. Contact time is the time needed for germicide solution to remain wet on the surface to achieve disinfection of the stated kill claim(s) on the manufacturer’s label. The proper ‘overall’ contact time for surface wipes is indicated on the product label as required by the EPA. The overall contact time is the highest kill time for the microorganisms tested. The technical data bulletins provided by manufacturers will outline contact time for different pathogens. It is always important for clinicians to review technical data bulletins before choosing a disinfectant and look at the contact times for pathogens of concern for their healthcare environment. Staff should be made aware of the overall contact times for surface wipes and directions for use which are listed on the product label. As previously mentioned, pre-moistened wipes must be used once and discarded. One wipe should not be used repeatedly for multiple surfaces, as this can lead to the tendency for wipes to lose moisture and thus be ineffective.”
“The primary purpose of a wipe should be its ability to remove a microbial burden from a surface,” Maillard says. “If the wipe is then discarded after ‘one usage’ and ‘one direction’ as we are recommending, then its ability to kill microorganisms might not be essential. Staff needs to be made aware to use a wipe only once and in only one direction. Manufacturers do not necessarily provide a protocol on how to use the wipes.”
A review of the proper usage of antimicrobial wipes in the healthcare environment is in order.
“Germicidal wipes should be used once and discarded,” Fleming explains. “Pre-moistened wipes should be applied to the surface and allowed to air dry. Attempting to take a towel to dry a surface that has be wet by a disinfectant to speed up the drying process defeats the efficacy of disinfectant on that surface. Allow the surface to air dry ensures greater contact time for killing pathogens. If gross soil is present i.e. heavy visible soil, blood, body fluids, one wipe should be used to clean and a second wipe to disinfect. The basic principles of disinfection is that soiled items must be cleaned before disinfection can be achieved. If no heavy or visible soil is present, but the item has had contact with patient or contaminated by hands, then using one wipe to clean and disinfect the surface is sufficient. Surfaces should be wiped and allowed to air dry. The friction created by using the wiping action will clean and disinfect. Depending on the size or area of surface to be disinfected, more than one wipe will be needed. The size of the wipe and the wetness of the wipe will determine if more than one wipe is needed.”
Manufacturers of antibacterial wipes are trying to leverage the heightened press on the clinical study to educate and increase awareness on the proper protocol for using surface disinfectants. “The Cardiff study essentially brings to light that surface disinfection products are not always used in a manner consistent with manufacturer’s labeling,” says Kathy Wie, marketing communications manager for Metrex Research Corporation. “Metrex cleaning instructions on our labels specifically state to use multiple wipes as a cleaning and disinfecting process. First, preclean by using a wipe to remove all visible gross debris. Use a second wipe to thoroughly wet the surface for three minutes to be effective as a bactericide and two minutes as a virucide. Repeated use of the product may be required to ensure that the surface remains wet.”
Wie continues, “I can’t emphasize enough the importance of having the surfaces wet for the time specified on the manufacturers’ labels. I suggest comparing wipes that are out in the market and select the wettest wipes to ensure that surfaces will be fully saturate for the recommended time. Also, compare wipe substrates. Look for strong and sturdy wipes that will pick up gross debris easily to reduce time during the pre-cleaning step.”
Some believe antimicrobial wipes could create a false sense of security in terms of elimination of pathogenic bacteria and viruses on surfaces. Maillard remarks, “Creating a false sense of security is a danger in using any products labeled as ‘antimicrobial.’ The wipes are no different. If microorganisms are removed effectively from a surface, then the risk of infection should decrease. This is where wipes should have a role to play. Increasing the antimicrobial effect of the wipes to ensure that the microorganisms removed are killed within the wipe is attractive and provides an additional protection for the end user. However, this might not be easy to achieve; different microorganisms, for example bacteria and viruses, will display different susceptibility, and might be expensive to develop: increasing the number of antimicrobial agents or the concentration of an antimicrobial agents will increase the cost a wipe.”