The Journal of Hospital Infection - Supplement 1

in minimising the spread of healthcare associated infections. Viable

organisms have been shown to persist in dry biofilms even after

terminal cleaning and disinfection. This work demonstrates the use of

dry biofilm testing to investigate the efficacy of various disinfectant

approaches.

Method(s):

Staphylococcus aureus

(NCIMB 9518) biofilms were

grown in Tryptone Soya Broth on 10 mm stainless steel discs (2B

finish) at 20

–

23°C for 12 days with rotation between wet and dry

phases at 37°C every 48 h. Dry biofilms were exposed to disinfectant

solutions with varying exposure times or wiped with disinfectant

wipes using the ASTM2967-15 test. For comparison wet biofilm of

aureus

grown for 48 h and dried

S. aureus

inoculum (EN 13727) were

used. Disinfectants included chlorine, glutaraldehyde and peracetic

acid. Assessment of efficacy measured: biomass reduction by crystal

violet staining, biofilm recovery indicated by a pH indicator colour

change and transfer of bacteria from surface to surface.

Results:

Treatment of dry biofilms with wipes showed 60

–

90%

reduction in biomass while biocidal solutions alone showed little

reduction in biomass. Both modes of treatment did not achieve the

ideal 3

–

4 log

reduction in CFU; some biofilm recovery was seenwith

the colorimetric medium after 24

–

48 h. Wet biofilms grown for 48 h

showed no recovery in the colorimetric medium after 24

–

48 h. Dry

biofilms, in contrast to

‘

wet

’

biofilms and planktonic cells, were found

to persist after biocidal exposure highlighting the need for an

improved anti-biofilm approach.

ID: 4981

Effectiveness of a multimodal intervention to improve the

standard decontamination practices among the healthcare

workers of Bangladesh

Lutfe Ara

, S.M. Niaz Mowla

, Shaikh Mahmud Kamal Vashkar

Delwar Hossain

, Utpal Kumar Mandal

icddr, b,

Dhaka Medical

College & Hospital

Background:

The necessity of proper disinfection and sterilization

cannot be overemphasized for successful prevention and control of

Healthcare Associated Infections (HAIs). Improper sterilization poses

serious threat of infections over the patients.

Aim(s)/Objective(s):

To assess the impact of a multimodal interven-

tion program to improve the decontamination practices of medical

instruments among the healthcare workers (HCWs) at secondary level

healthcare facilities in Bangladesh.

Method(s):

A yearlong quasi experimental study was conducted at

two secondary level healthcare facilities in Bangladesh, where a total

of 772 HCWs participated that included physicians, nurses, laboratory

technicians, ward boys and cleaning staff. The multimodal interven-

tion program consisted of education on standard decontamination

process, skill enhancement through on job training and improvement

of decontamination facilities. Compliance to standard decontamin-

ation practices was measured through direct observation before and

after the intervention.

Results:

Continuous improvement of compliance on standard

methods of disinfection and sterilization was seen after the interven-

tion. Remarkable compliance was achieved- 78.95% at the Institute

of Child and Mother Health (ICMH) and 86.95% at General Hospital,

Sirajgonj (GHS) (p < 0.0001). Indicator tape for sterilization was

introduced at both hospitals and the compliance significantly

increased from 0% to 57.90% at ICMH and 0% to 65.22% at GHS

(p < 0.0001). Cleanliness of sterilization room improved from 63.64%

to 89.47% at ICMH and 43.59% to 95.65% at GHS.

Discussion and/or Conclusion(s):

The study results show that the

implemented multimodal intervention improved the standard decon-

tamination practices among the HCWs, which in turn will play a

critical role in preventing and controlling healthcare associated

infections.

ID: 4986

Can a single-bed space within a multi-bedded bay be safely

decontaminated with UVC without posing a risk to other patients

and staff?

Jenny Child

, Samantha Horridge

, Andrew Weedall

Douglas Clarkson

Harrogate & District Foundation NHS Trust,

University Hospitals of Coventry & Warwickshire

Background:

Decontamination of single bed-spaces within multi-

bedded patient bays with HPV or UVC can be logistically difficult to

achieve if emptying the whole bay of patients puts too much

operational pressure on the hospital as a whole.

UVC is easily blocked by solid objects including fabric and glass.

Aim(s)/Objective(s):

The aim of this study was to establish whether it

would be safe to use a UVC source to decontaminate a single-bed space

within a multi-bedded bay screened only by standard hospital privacy

curtains.

Method(s):

The study was carried out a clinical simulation rooms in

the education centre of University Hospital, Coventry, fitted out as a

three-bedded bay found elsewhere in the acute hospital. Each bed

space is fitted with standard issue flame-retardant 100% polyester

curtains (Sunlight, UK).

A UVo

™

system (Hygiene Solutions, Kings Lynn, UK) was operated

within a bedspace behind closed privacy curtains, and UV levels

outside the curtains measured using a Bentham dmc150 double

monochromator system (Bentham Instruments Ltd, Reading, UK)

spectrum range 250

–

410 nm.

Measurements at head, abdomen and ankle heights were made with

the use of a polystyrene, body shaped maniken placed outside the

closed curtains.

Results:

The lowest value of effective treatment dosewas equivalent to

around 11 times that of the maximum permissible UV exposure and

the maximum treatment dose was around 260 times this exposure

limit.

Discussion and/or Conclusion(s):

It would not therefore be advisable

to operate a UVC system with only hospital curtains screening off the

bedspace from other patients or staff.

ID: 4997

Air and steam still do not mix

–

failure of non-vacuum benchtop

steam sterilizers

Andrew Smith

, Sandra Winter

, David Lappin

, George McDonagh

Brian Kirk

University of Glasgow,

3M Healthcare

Background:

Although steam sterilization failures have been reported

due to failure to remove air from the load, a classic example being the

Devonport incident from the 1970

’

s. There is still widespread denial

in some healthcare groups that the presence of air can contribute to

sterilization failures.

Aim(s)/Objective(s):

The aim of this study was to investigate steam

penetration into dental handpieces using benchtop non-vacuum

sterilizers commonly used in dental practice.

Method(s):

Three different types of handpieces were investigated for

steam penetration into handpiece lumens using chemical indicators

(CI), biological indicators (BI) and thermocouples/data loggers (TC).

Non-vacuum (type N) Benchtop steam sterilizers were investigated

in both the laboratory and general dental practice setting. In the

laboratory we tested 4 different makes with 3machinemodels for each

make. In the General Dental Practice setting we tested seven non-

vacuum benchtop sterilizers.

Results:

Results in the laboratory demonstrated BI failure for 15/1152

tests, CI failure for 9/1152 tests, typical delays in reaching sterilization

temperature ranged from 0 to 165 seconds detected using TC. In

general dental practice we detected BI failure rate of 34/378 tests, CI

failure rate of 25/378 tests. And TC failure rates of 28/42 (defined by a

temperature delay of 2°C, SHTM 2010).

Discussion and/or Conclusion(s):

In conclusion, we have demon-

strated that type N sterilization of dental handpieces is unreliable due

to trapped air in handpiece lumens. As a minimum we recommend

Abstracts of FIS/HIS 2016

–

Poster Presentations / Journal of Hospital Infection 94S1 (2016) S24

–

S134

S67