Contamination of Bed Linen: Factors in Microbial and Allergen Accumulation

By John Fallon, PhD

Federal health officials reported last month that antibiotic-resistant bacteria infect at least two million Americans every year, and at least 23,000 die from those infections. This harsh reality of hospital infections means that there is no doubting the importance of their control and prevention.  Limiting the spread of infection will require novel infection control strategies. A key element of this strategy is to control the dispersal of microbes via contaminated bed linen, mattresses and other points of close contact with infected individuals (Thilagavathi and Kannaian, 2008).

As modern day hospital infection control measures improve, there is an increased focus on bed linen and associated materials as possible sources of infection. Fijan and Turk (2012), identify incidences of Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa and Enterobacter aerogenes surviving temperatures of 60 degrees Celsius during standard washing processes. A study by Creamer and Humphries, (2008) outlined many of the issues posed by inadequate cleaning of hospital beds. It was advocated that decontamination should be performed once a week in cases where patients were at a particular risk of infection. The optimal bed linen described was that which is easily washed and dried and has the lowest potential to harbor microorganisms.  In addition, it is reaffirmed that pillows and mattresses warrant the greatest level of attention due to their proximity to patients undergoing care. The correct maintenance of storage presses and trolleys as part of any decontamination process is highlighted as an area that should also be considered as part of such a strategy.

A healthy individual is a reservoir of microbial contaminants that for the most part do not result in any adverse health effects. The innate and adaptive immune system combines with the physical barriers of the body to protect individuals from infection.  As humans constantly shed skin, hair, saliva and sebaceous particles from their bodies in bed, the knock-on effect is the accumulation of microorganisms in bed linen. However, the development and persistence of dust mites and dust mite allergen (Der p1 or Der f1) in pillows is a major factor for people with immune hypersensitivity. It has been established that Der p1 levels in house dust exceeding 2 µg/g are sufficient for eliciting an allergic/asthmatic response (Platts-Mills et al., 1997). In instances where an individual is immunocompromised, has an underlying infection, or has other predisposing factors such as asthma that make them susceptible to infectious diseases the environment in which a person finds themselves may have a strong influence on their health.

The issues surrounding textiles in bedding and their role in reducing the risk of diminishing the health of individuals is not limited to the hospital setting. Recently, a national pillow health check performed in Ireland in conjunction with Gabriel Scientific and Airmid Healthgroup laboratories gave some indication as to the potential levels of contaminants present as we sleep. The study unveiled extremely high levels of bacteria and fungi in a selection of pillows that were analyzed. In addition, the concentration of dust mite allergen was found in some cases to be above the levels that have been demonstrated to elicit severe allergenic responses. Interestingly, a survey undertaken by those who submitted pillows for testing showed occurrences of contamination were frequently associated with factors such as the pillows being older, lower frequency of cleaning and reporting of poor sleep quality. While further research in this area is warranted in order to provide meaningful statistical correlations between levels of contamination and the development and persistence of clinical manifestations, this work has strengthened the opinion that an improvement of an individuals health maybe enhanced by more frequent laundering of bed linen using better methods.
 
In order to protect individuals from infection the development of fabrics and textiles has lead towards a more active means of preventing microbial growth. The practice of impregnating textiles with divalent cations such as silver or copper as a means to disrupt membrane stability has been proposed as a solution with claims of antifouling properties and other claims such as odor control and prevention of topical infection (Borkow and Gabbay, 2004, Haug et al., 2006) The principal weakness of this technology is that there is a leaching effect over time during conventional washing of fabrics, depending on the manufacturing process, which may reduce the efficacy of such treatments (Benn and Westerhoff, 2008).  In addition there is a growing body of evidence to suggest that this may pose an environmental risk as bioaccumulation of silver in aquatic life result in toxicity for marine life (Mathivanan et al., 2012). Nevertheless the application of such textile design and the development of new antimicrobial technologies could represent an invaluable tactic in controlling the spread of infections. Looking to the future, a combination of bed protection systems that are easily cleaned as well as the application of novel technologies in the construction of antimicrobial textiles could be one way in which the spread of infections is controlled.

John Fallon, PhD, is a senior microbiologist at Airmid Healthgroup, which helps clients with products and services related to residential and commercial indoor environments to differentiate their customer offerings through health relevant marketing claims. Clients include Dyson Inc., LG Electronics, Stanley Steemer, Shaw Industries, Fellowes, Spring Air, Tarkett and Kenmore. Airmid creates value for clients through a number of collaborative strategies, including field research projects, environmental test chamber studies and licensing its own intellectual property. Airmid specializes in studying the relationship between allergens, viruses, bacteria, molds or other ultra-fine particles in the air and on surfaces to the spread of illness and disease in buildings. As a leading authority on biomedical and aerobiology research, they use this deep domain knowledge to improve products and services to make the indoor environment as healthy as possible. For more information, visit www.airmidhealthgroup.com.

References:
Benn TM and Westerhoff P. (2008). Nanoparticle silver released into water from commercially available sock fabrics. Environmental Science and Technology. 42 (11): 4133-4139.

Borkow G and Gabbay J. (2004). Putting Copper into Action: Copper-impregnated Products with Potent Biocidal Activities, FASEB Journal. 18(14):1728-1730

Craemer E and Humphreys H. (2008). The contribution of beds to healthcare-associated infection: the importance of adequate decontamination. Journal of Hospital Infection. 69(1): 8-23.

Fijan S and Turk SS. (2012). Hospital Textiles, Are they a possible vehicle for healthcare associated infections. International Journal of Environmental Research and Public Health; 9 (9):3330-3343.

Haug S, Roll A, Schmid-Grendelmeier P, Johansen P, Wüthrich B, Kündig T and Sent G, (2006). Coated Textiles in the Treatment of Atopic Dermatitis. Current problems in dermatology. 33:144-151.

Mathivanan V, Ananth S, Ganesh P and Selvisabhanayakam P (2012). Role of Silver Nanoparticles: Behaviour and Effects in the Aquatic Environment A Review. International Journal of Research in Biological Sciences; 2 (2):77-82.

Platts-Mills TA, Vervloet D, Thomas WR, Aalberse RC and Chapman MD. (1997).  Indoor allergens and asthma: report of the Third International Workshop. Journal of Allergy and Clinical Immunology; 100(6):S1-S24.

Thilagavathi G and Kannaian T. (2008). Dual antimicrobial and blood repellent finishes for cotton hospital fabrics. Indian Journal of Fibre and Textile Research. 33:23-29.