The Journal of Hospital Infection - Supplement 1

ID: 4905

Influence of a probiotic-based sanitizing methods on surface

pathogen persistence and resistance: an effectiveness and safety

study

Elisabetta Caselli

, Maria D

’

Accolti

, Paola Antonioli

, Luca Lanzoni

Maddalena Coccagna

, Maria Teresa Camerada

, Sante Mazzacane

University of Ferrara,

CIAS, University of Ferrara,

S. Anna University

Hospital, Ferrara

Background:

Contamination of hospital surfaces can contribute to

transmission of healthcare-associated infections (HAIs), representing

a global concern. Chemicals-based cleaning shows limitations in

controlling surface bioburden, and can select resistant species.

Recently, a system based on detergents containing probiotics of the

spore-forming

Bacillus

genus (PCHS) was shown to decrease surface

pathogens up to 90% more than conventional disinfectants.

Aim(s)/Objective(s):

Here we wanted to analyse the impact of PCHS

on the drug-resistance features of the hospital surfaces microbiota,

and to assess its safety of use.

Method(s):

Microbial drug-resistance was analysed by a microarray

detecting 84 resistance-genes in the total microbiota and in individual

isolates, and confirmed by conventional antibiograms. Also, a four-

year microbiological surveillance was implemented, evaluating the

presence of

Bacillus

strains in all the clinical samples of the patients

admitted to PCHS-treated hospitals.

Results:

PCHS use induced a drop (up to

−

99%) of resistant pathogen

strains, rather than selecting them. Notably, detergent-

Bacillus

strains

remained genetically unmodified even after years of continuous

contact with surface pathogens, and no infections attributable to

Bacillus

were observed in 32,139 analysed samples from seven

hospitals.

Discussion and/or Conclusion(s):

Results show that PCHS application

can effectively reduce the number of pathogens and their drug

resistance. Furthermore, the genetic stability of PCHS-

Bacillus

trains,

together with the absence of HAI attributable to probiotic

Bacilli

suggest that they do not have the ability to cause infections, even in the

subjects at higher risk for adverse events, such as hospitalized

patients, and support the safety of environmental use of probiotics

for sanitation purposes.

Topic: Environment

ID: 4420

Transfer frequency of dry surface biofilm in health-care

environment

–

the role of health care worker

’

s hand

Durdana Chowdhury, Shamaila Tahir, Mark Legge, Honghua Hu,

Khalid Aljohani, Anand Deva, Karen Vickery.

Macquarie University

Background:

Hospital environmental surfaces become contaminated

by pathogens shed by infected patients and can survive for extended

periods when incorporated into dry surface biofilms (DSB). Within

biofilms, bacteria are protected from desiccation and increased

tolerance to removal by cleaning agents and disinfectants. We

hypothesise that pathogens in DSB play a significant role in the

endemic transmission of healthcare-associated infections.

Aim(s)/Objective(s):

This study aims to determine if DSB can be

transmitted from hospital surface to healthcare worker

’

s hands.

Method(s):

DSB of

Staphylococcus aureus

was grown in vitro on

polycarbonate and glass coupons in CDC bioreactor over a period of 12

days with periodic nutrition interspersed with long periods of

dehydration. Each coupon had 10^

bacterial cells. Transmission was

tested using gloved and ungloved hands via various materials (plastic

and glass coupon and cotton sheet) before and after treatment with 5%

neutral detergents.

Results:

Transmission of organisms was 10 times higher with bare

hands than gloved hands. Both nitrile gloves and surgical gloves

transmitted approximately 6 times the bacteria than latex gloves.

Following hand contamination with DSB, transmission to 20

subsequent surfaces was highly possible. Cotton bed sheet also

showed higher rate of transmissibility. It is astonishing that, 7.3%

organism can pass through cotton sheet to contaminate skin of hands.

Surprisingly, DSB treated with 5% neutral detergent increased the

transmission rate of DSB bacteria tenfold.

Discussion and/or Conclusion(s):

DSB is highly transmissible. It is

higher with bare hand and can be transmitted to the patient from bed

mattress, through the bed sheet.

ID: 4503

Non-slip socks: A potential reservoir for transmitting multidrug

resistant organisms in hospitals?

Nikunj (Nik) Mahida, Tim Boswell.

Nottingham University Hospitals

Background:

Falls and fall-related injuries are common within acute

healthcare settings. In response to patients admitted with unsuitable

or inappropriate footwear, a number of hospitals have introduced non-

slip socks to reduce falls.

Aim(s)/Objective(s):

This study evaluates whether non-slip socks can

be become contaminated with multidrug resistant organisms found

on the floor.

Method(s):

54 pairs of used socks and 35 environmental floor samples

were obtained from 7 wards in a tertiary referral hospital. Socks were

anonymously collected frompatients by offering a new pair of non-slip

socks in exchange for the in-use pair. On each ward where socks were

collected, five floor areas (2 ward corridors, 3 toilets) were sampled

using a Polywipe

™

sponge.

Results:

Vancomycin resistant enterococci (VRE) were detected from

46 socks (85%) and Meticillin-resistant Staphylococcus aureus (MRSA)

from 5 (9%). Environmental sampling cultured VRE from 24 floor

samples (69%) and MRSA from 6 floor samples (17%). Clostridium

difficile was not detected from any sample.

Discussion and/or Conclusion(s):

The study demonstrates that non-

slip socks can become contaminated with multidrug resistant

pathogens. Patients not only use them to walk to various parts of the

hospital during the inpatient journey but also wear them in bed. It

suggests a potential route for cross-transmission, which thus far has

not been considered.

ID: 4550

Comparison of environmental sampling methods for the

investigation of an outbreak of Group A Streptococcus

Amelia Joseph

, Vivienne Weston

Nottingham University Hospitals/

Health Education East Midlands,

Nottingham University Hospitals

Background:

There is no guidance on the optimal method of sampling

the non-healthcare environment for Group A Streptococcus (GAS)

during an outbreak.

Aim(s)/Objective(s):

To compare methods of sampling soft furnish-

ings in a residential home setting during an outbreak of GAS.

Method(s):

Three cases of GAS infection (emm type st1.0) and eight

asymptomatic cases were identified over a four month period in a

residential home setting. During the outbreak we sampled soft

furnishings (carpets, curtains and soft furniture) using three

methods: standard swabs onto blood agar; Polywipe

sponges into

brain heart infusion broth with subculture to streptococcal selective

agar; and blood agar sweep-plates. Isolation of GAS was compared at

24 and 48 hours.

Results:

All standard swab samples were negative. GAS was isolated

from the patients

’

carpets by sweep-plate method in three, and by

Polywipe

sponge method in two, of the four samples. Curtains in one

patient

’

s room and in the communal living room were positive by

sweep-plate method, but negative by Polywipe

sponge method. A

footstool in the communal living room was positive by both sweep-

plate and Polywipe

sponge methods. There were no additional

positives at 48 hours compared to 24 hours of incubation. All

environmental isolates were emm type st1.0.

Discussion and/or Conclusion(s):

The sweep-plate method is a

rapid and effective way of sampling soft furnishings for GAS.

Abstracts of FIS/HIS 2016

–

Oral Presentations / Journal of Hospital Infection 94S1 (2016) S11

–

S21

S18