Hospitals Battle MRSA: Why Infection Control Arsenals Need Many Weapons

If you read UK newspapers you get the impression that MRSA is public health enemy #1. Fortunately the public’s focus on MRSA has helped to raise awareness and resources to reduce infections caused by this bacterium.

An excellent study of technology designed to eradicate MRSA is found in a recent issue of the Journal of Hospital Infection. Researchers assessed the short and long term effects of cleaning a hospital ward with Hydrogen Peroxide Vapor (HPV). Due to its oxidative properties, hydrogen peroxide is effective at eliminating many types of bacteria.

During the five month study, researchers measured MRSA contamination for the three months prior, and four weeks after an ICU was cleaned using HPV. Scientists used a machine like this one to create the vapor that was released inside the sealed, nine bed ICU. Previous studies have noted that HPV is considered a ‘big gun’ in disinfection, affording significant reduction of bacteria when combined with surface cleaning.

In the months prior to the HPV treatment, MRSA was isolated from 11.2% of sample sites. In the hours immediately following the HPV, no MRSA was isolated from the environment. The HPV did its job, end of story. Not quite.

The researchers wanted to look for MRSA after the HPV treatment, when real patients populated the ward. In less than 24 hours, the MRSA was back in the ICU:

“Twenty-four hours after the readmission of patients, MRSA was isolated from five environmental sites. All of the strains were indistinguishable from the strain with which the patient in bed space 8 was colonized, but the environmental contamination was not confined within that bed space.”

Despite the effectiveness of the ‘big guns’ (HPV), MRSA returned. In fact, detected MRSA surpassed the pre-HPV levels (11.2% v. 16.3%). Use of HPV is a great idea, but it cannot be the Infection Control Practitioner’s only weapon. Disinfection is an ongoing battle fought everyday, in every ward. Vigilance and multi-faceted approaches are the keys to long term success.

VIGILAIR® can be an important part of that strategy. Deployed within the Hospital’s air handlers, VIGILAIR® constantly disinfects the air through a combination of ultraviolet germicidal irradiation (UVGI) and high efficiency filtration. The technology is more than infection control, it is infection prevention.

As we always say, there is no panacea in the fight against MRSA, H5N1 and HAI. There needs to be a cross-discipline, evidence based strategy to identify, and eradicate all pathogen reservoirs within a hospital. With changes looming on the reimbursement horizon, this strategy will keep patients and hospitals healthy.

A white paper on airborne pathogens is available here.

Original Study:

K.J. Hardy, et al. Rapid recontamination with MRSA of the environment of an intensive care unit after decontamination with hydrogen peroxide vapour. Journal of Hospital Infection (2007) 66, 360-368

Image:

Bioquell

UK University Leeds the way in Airborne Infection Research

Some of the most compelling and important research in airborne contamination control originates from a progressive university in the resilient city of Leeds. Known as a manufacturing center (or is it centre?), Leeds has managed to diversify itself, evolving into a hub for international banking and business services.

Researchers at the University of Leeds are proving that hospital design plays a major role in healthcare, specifically the growing problem of hospital acquired infections. Perhaps the key to their success is an understanding of the role that the indoor environment plays in disease transmission. According to Leeds professor Andrew Sleigh, “There is evidence that 10 to 20% of infections are spread through the air, but until now, their role in the infection chain has been largely overlooked, as doctors tend to emphasise the importance of washing hands and avoiding physical contact.” I guess being open to new ideas can lead to new discoveries.

Another key could be the University’s cross-disciplinary approach to learning. Leeds University prides itself on innovative study programs that give students creative options:

“Many of its research initiatives cross traditional subject boundaries and Leeds currently promotes projects through 58 inter-disciplinary centres and seven research schools.”

This approach is apparent in the Pathogen Control Engineering Research Group within Leeds’ School of Civil Engineering:

"Our multi-discipline approach brings together investigators from a variety of backgrounds including public health engineering , fluid mechanics , building services engineering and microbiology . This has produced a team with the all-round strengths required to undertake rigorous research in the field of aerobiology and indoor air quality.

Leeds’ advances demonstrate both the challenge and the promise of airborne infection research. Research in this field requires the talents and intelligence of participants from several disciplines. This approach was taken by scientists who reviewed research papers published between 1960 and 2005 on airborne disease transmission (1). More than 200 papers were assessed by a team of 15 experts in epidemiology, virology, environmental health and engineering. This study, and the work at Leeds, shows that greatest discoveries are found at the nexus of divergent technologies.

Recent Leeds Research

Although not entirely complete, Leeds researchers released some results from recent airborne pathogen testing. According to Professor Sleigh's research, infectious particles are distributed within hospital wards.

“Although diseases such as tuberculosis are widely accepted as being airborne, others may also be spread this way. Numerous bacteria-carrying particles - such as tiny flakes of human skin - can be widely dispersed into the air within hospital wards through routine activities, and potentially contribute to the risk of infection for patients.”

PhD students Abigail Hathway and Katherine Roberts used a laser counter to assess the particle concentration of hospital ward air. Their data indicate that normal staff operations such as making rounds, closing drapes and changing patient beds significantly affected concentrations of airborne particles.

These findings add important new insight to the role of the airborne route in infection transmission. This research will be used by the UK’s National Health Service to update guidelines for ventilation and infection control. According to Ms. Hathaway, more research will be done in the upcoming months, with an eye on possible publication in 2008.

Diverse curriculum, public-academic partnerships and accomplished professors are among the reasons why Leeds attracts more undergraduate applications than any other UK university. Plus, any school that Mark Knopfler attended has got to be way cool!

1. Li Y, et al. Role of ventilation in airborne transmission of infectious agents in the built environment—a multidisciplinary systematic review. Indoor Air 2007; 17: 2-18.

Best of the web

Keeping track on how states are dealing with legislation on Hospital Acquired Infection reporting? Then check out this blog:

About Health Transparency

You can easily see the status of legislation that mandates the reporting of quality measures. While you're there, you may find the 'Cost Measures' link interesting. You can see the disparity in costs/payments for various procedures in several communities. As far as I can tell, the site is a public/private partnership that is legit, not a shell shill for an industry group.