Healthcare Hygiene magazine November 2019 | Page 37

healthcare textiles/laundry
By Carol McLay, DrPH, MPH, RN, CIC, FAPIC
Defining and Measuring
‘Hygienically Clean’
L
aundry services play a critical role in a healthcare
facility’s infection prevention and control program.
Healthcare textiles (HCTs) include bed sheets, pillowcases,
blankets, towels, personal clothing, patient apparel, em-
ployee uniforms, scrub suits, gowns, and drapes for surgical
procedures. Contaminated textiles often contain large
numbers of microorganisms from body substances such as
blood, skin, stool, urine, vomitus, and other body tissues
and fluids, and it is important to ensure that pathogens are
not transferred to patients or healthcare workers.
In addition to normal microbial skin flora, organisms
commonly found on HCTs include gram-negative bacteria,
coagulase negative staphylococci, and Bacillus species. 1
These organisms have the ability to bind to textiles and may
survive for as long as 90 days. 2-3 Staphylococcus aureus
and Pseudomonas aeruginosa in particular have high ratios
of binding (80 percent) to polyester or acrylic fibers. Nylon
fibers bind S. aureus at low ratios, but P. aeruginosa at
intermediate ratios. The binding rate for cotton fibers was
reported to be less than 10 percent. 4
In addition to bacteria, molds and viruses including
rotavirus and parainfluenza virus have been cultured from
hospital textiles. 1
HCTs have been implicated in hospital outbreaks of
fungal and bacterial pathogens; 12 such outbreaks have
been reported worldwide in the past 43 years affecting
350 patients. 5
Investigators have examined the connection between
healthcare textiles and infectious disease outbreaks and their
conclusions emphasize that fact that correct laundering of
healthcare textiles is an important measure for preventing
healthcare-associated infections (HAIs). Through a combi-
nation of soil removal, pathogen removal, and pathogen
inactivation, contaminated laundry can be rendered
hygienically clean.
Hygienically clean is defined by the Association for the
Advancement of Medical Instrumentation (AAMI) as “free
of pathogens in sufficient numbers to cause human illness.” 6
However, AAMI does not quantitatively define the meaning
of “sufficient numbers.”
The Centers for Disease Control and Prevention (CDC)
also does not provide a quantitative value for hygienically
clean textiles in their “Guidelines for Environmental Infec-
tion Control In Health-Care Facilities” but do state that
proper laundering processes should result in a 3-4 log10
reduction (approximately 99 percent) of microorganisms. 7-9
A postprocess level of 10-100 colony-forming units (CFUs)
has been suggested. 5
www.healthcarehygienemagazine.com • november 2019
The CDC does not currently recommend routine mi-
crobiologic sampling of clean textiles, however, sampling
during outbreak investigations is appropriate if epidemiologic
evidence indicates a role for healthcare textiles and clothing
in disease transmission. 8
Microbiological testing of laundered textiles is conduct-
ed routinely in Europe and Australia as a requirement of
their healthcare regulation programs. 10-11 The Certification
Association for Professional Textiles Services Administration
(CAPSTA), which has 400 members in 15 European countries,
Japan, China, and the United Arab Emirates, has established
safe microbial levels for laundered textiles as 20 CFU per
square decimeter (PSD). This microbial threshold has also
been adopted by the European Union.
In the United States, microbial levels on hygienically clean
textiles have not been reliably measured. To address this gap,
Sands, et al. (2019) collected 48 healthcare textile samples
from hygienically clean linen on three different patient
care units at two separate points in time. 12 The researchers
reported that only 27 percent of the samples had a total
aerobic microbial count below the expected 100 CFU level;
the values ranged between 9 and 40,000 CFUs. For yeast
and mold counts, more than 81 percent had counts of
100 CFUs or less. Interestingly, the overall average aerobic
bacterial, yeast, and mold counts was lower after 24 hours
of storage on the patient care units compared to the time
of delivery. The authors theorize that the textiles may have
been slightly damp, then were folded and placed in plastic
carts for delivery allowing microorganisms to proliferate.
The textiles would then have had time to dry before the
second sample was obtained.
Microbial testing of textiles is a component of the
Healthcare Laundry Accreditation Council (HLAC)’s recently
introduced Laundry Process Monitoring ToolKit, which
validates the effectiveness of a laundry’s processes by mea-
suring the number of microorganisms found in a laundry
on hard surfaces, in the air, on linen, in the water and on
employee hands.
HLAC is a nonprofit organization that inspects and ac-
credits laundries that process reusable textiles for hospitals,
nursing homes and other healthcare facilities. HLAC’s core
purpose is to establish and maintain criteria and procedures
for accreditation. The HLAC Accreditation Standards are
established as the minimum acceptable practice for the
preparation of hygienically clean, reusable healthcare textiles
for patient care, implemented and executed by accredited
laundry facilities processing reusable healthcare textiles. 13
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