Recent studies have demonstrated that several major nosocomial pathogens are shed by patients and contaminate hospital surfaces at concentrations sufficient for transmission, survive for extended periods, persist despite attempts to disinfect or remove them, and can be transferred to the hands of healthcare workers. Evidence is accumulating that contaminated surfaces make an important contribution to the epidemic and endemic transmission of Clostridium difficile, vancomycin-resistant enterococci, MRSA, Acinetobacter baumannii, Pseudomonas aeruginosa and norovirus, and that improved environmental decontamination contributes to the control of outbreaks.

by Dr Jonathan A. Otter

Hospital patients shed pathogens into their surrounding environments but there is debate over the importance of the resulting surface contamination as a source for subsequent transmission. Several studies in the early 1980s suggested that the hospital environment contributed negligibly to endemic transmission. Recently, however, there has been a reassessment of the role of contaminated surfaces in the transmission of nosocomial pathogens.

Pathogen transfer from an affected patient to a susceptible host occurs most commonly via the hands of healthcare workers (HCWs) but contaminated objects, surfaces and air can be either directly or indirectly involved in transmission [Figure 1]. Here we review evidence that nosocomial pathogens are shed by patients and can contaminate hospital surfaces at concentrations sufficient for transmission, can survive for extended periods, can persist despite attempts to disinfect or remove them and can be transferred to the hands of healthcare workers (HCWs) [1]. We also review evidence that improved environmental hygiene can help to bring outbreaks under control and reduce endemic nosocomial transmission.

Pathogens are shed into the hospital environment
Several important pathogens including Clostridium difficile, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), Acinetobacter baumannii and norovirus can be shed by patients into the hospital environment and share the ability to survive on dry surfaces for extended periods. Under certain conditions, C. difficile spores, VRE, MRSA and Acinetobacter spp. can survive for 4-5 months or more on dry surfaces and norovirus can survive for a week or more [2]. Wide variation in the reported frequency of environmental contamination can be explained by several factors, including the degree of shedding by the patient, the culturability of the organism, the sampling methodology and the ease of contamination (or difficulty of cleaning) of the particular environment. Methodological differences in sample collection and culture make comparisons between studies difficult and in some cases the true level of environmental contamination may be underestimated.

Patients are the prime source of contamination, so surfaces in the vicinity of patients that are touched frequently by healthcare workers and patients, termed

The ECRI Institute is a US-based, independent, non-profit organisation that researches the best approaches to improving the safety, quality and cost-effectiveness of patient care. ECRI Institute experts have compiled a Top 10 list of important technologies and technology-related issues that hospital and health system leaders should pay close attention to this year. The list takes into account the convergence of critical economic, patient safety, reimbursement, and regulatory pressures. The effort began with an open call for nominations throughout the ECRI Institute. This resulted in a nominated list of more than 30 technologies and related issues. The list was then circulated among key ECRI Institute thought leaders who individually ranked their Top 10 choices. Once all rankings were compiled, the top 5 technologies emerged fairly quickly. A number of technologies competed for rankings 6 to 10, so a ratings consensus panel was convened to reach agreement on the final Top 10.

For the benefits of its readers in healthcare communities outside the USA, International Hospital presents the essence of the ECRI Top10 watch list in a series of three articles to be published in consecutive issues of the magazine. In this first article, we take a look at the three imaging technologies ranking number 3, 4 and 8 in the Top 10

Number 3. Digital Breast Tomosynthesis
Adoption of full-field digital mammography since it became commercially available in the United States in 2000 has been slow because of controversies that included costs, data storage needs, disagreement about risks and benefits of screening by age group, and trade-offs between how to reduce false positives without increasing false negatives. As of July 2011, 22% of mammography facilities still operated film-based mammography.

Enter the new twist on full-field digital mammography

Multiple strategies have been deployed to reduce catheter associated urinary tract infections. These include employing correct hand-washing procedures, avoiding breakages in the urinary collection system and taking measures to prevent commensal bacteria from the patient contaminating the catheter. As well as changes in clinical practice, we need to be mindful of the potential technological and equipment solutions. This article highlights the potential use of silver-alloy urinary catheters to reduce catheter associated urinary tract infections.

by Michelle Beattie

Catheter associated urinary tract infections are often accompanied by an increased period of hospitalisation and morbidity, resulting in poor outcomes for patients as well as their families, and significant economic costs to service providers. Despite the high risk of infection and other potential complications, urinary catheters have many beneficial uses in healthcare including diagnostic, prophylactic and therapeutic uses. Regardless of whether the urinary catheter is used for therapeutic or diagnostic purposes, catheters should only be inserted when deemed absolutely necessary, due to their association with significant morbidity and mortality [1].

Catheterisation and sources of infection
As urinary catheterisation involves the insertion of a catheter into the bladder via the urethra, the patient is at a higher risk of infection, as essentially the body treats the presence of a catheter as a foreign body. The body