Hygiene in the non-clinical environment

Dirk Bockmühl

Hygiene at home?

Gerd had rather spent more money in toilet cleaning agents…

Home hygiene: the consumer’s view

Hygiene threats are mostly found outside my home

According to a GfK survey for the „Apotheken-Umschau“ 2006

Notifiable infections in Germany (2008)

Source: RKI

Household-associated infections

Norov

irus

Rotav

irus

Salmon

ella

Campy

lobac

ter

Hepat

itis A

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

outside

at home

Krause et al.: Emerg Inf Dis 13(10) (2007)

The key message

• The domestic environment is one of the most important sources for infectious diseases

• These infections are predominately food-borne

The risk of infection at home

7

Risk

Source: IFH

Risk

Source: IFH

The risk of infection at home

Decontamination of food contact surfaces

The dishwasher: a risk?

Dishwashers host black yeasts

Zalar et al. (2011)

Dishwashers host black yeasts

?But is there a risk of infection?

Estimation of infection risk

1.Pathogenic microbes?

2.Routes of infection?

3.Exposition?

4.Risk factors?

Groups of higher risk: YOPIsYoung Old

Pregnant Immunocompromised

Antibacterial effect of hand dishwashing

Mattick et al.: Int J Food Microbiol 85 (2003) 213– 226

47 50 53 57 600

10

20

30

40

50

60

Soa

king

tim

e [m

in]

Temperature [°C]

Water

Water + Detergent

Time needed to reduce 99,9% of Salmonella

The „killer“ sponge

Enriquez et al. Dairy Food Environ. Sanitation. 17:20-24.

102 – 107 microbial cells

per gramm

SEM-photograph: A. Hinnemann, Rhine-Waal University of Applied Sciences

How to sanitize a kitchen sponge

Sharma et al. Food Control 20 (2009) 310–313

The dishwasher kills…

The dishwasher kills…

…bacteria!

Thus it is an important means to ensure decontamination of food-contact surfaces

The risk of infection at home

Risk

Source: IFH

The washing machine as source of germs

Will we all die now?

Infections and laundering

Fungal infections(Athlete‘s foot, Candida)

Viral infections(Noroviruses)

Inactivation of Norovirus via laundering

Lemm et al. Tenside, Surfactants, Detergents (submitted)

Detection of viral RNA on fecally contaminated textiles

Challenge: low temperatures

1972 1987 1996 2001 2005 2008 2009 20100

10

20

30

40

50

60

70

0

10

20

30

40

50

60

70

80

90

100

T [

°C]

%

Medium washing temperature

Textiles washed at ≥60°C

Survey on german householdsSource: IKW Sustainability Report 2010

Wearing

Drying

WashingStorage

Hygiene in the wash- and use-cycle

Inpu

t of

m

icro

orga

nism

sR

educ

tion

of

mic

roor

gani

sms

Wearing

Drying

WashingStorage

Hygiene in the wash- and use-cycle

Inpu

t of

m

icro

orga

nism

sR

educ

tion

of

mic

roor

gani

sms

Wearing

Drying

WashingStorage

skin floraexcretions

biofilms

crosscontami-

nation

fungal spores

dust

dehydrationtemperature

chemistrymechanics

temp.

dehydration

Hygiene in the wash- and use-cycle

Challenges

Challenges

Wich microbes?

Quantity?

Challenges

Machine impact?

Challenges

Impact of drying and ironing?

10

100

1000

10000

100000

cfu/

cm2

After drying

After laundering

After use

What happens when you wash your towels?

Blümke et al., EDC conference 2011

10

100

1000

10000

100000

cfu/

cm2

After drying

After laundering

After use

What happens when you wash your towels?

Blümke et al., EDC conference 2011

10

100

1000

10000

100000

cfu/

cm2

After drying

After laundering

After use

What happens when you wash your towels?

Blümke et al., EDC conference 2011

The washing machine as a reservoir for germs

• Microbial colonisation of the rinsing chamber is independent of the chosen temperature

• Contamination after the main wash cycle

Another real-life study…

Analysis of Laundry in Nursery Homes

Analysis of Laundry in Nursery Homes cf

u /

100

cm

2

Before laundering

After laundering

After drying

Survey on 16 nursery homes in the district of KleveBertelmann et al., DGHM conference 2012

Individual reduction factors

Nursery home #

Log

redu

ctio

n (b

efor

e/af

ter

laun

derin

g)

Bertelmann et al., DGHM conference 2012

Impact factors on laundry hygiene

Nursery school # 1 2 3 4 5 7 8 9 12 13 16 17 18 21 23 28

Reduction factor before/after washing

0,3 9,7 1,1 12,8 6,5 11,0 5,2 0,1 1,6 3,3 9,0 23,0 1,2 28,5 7,5 1,2

Machine age (y) 15 2 15 7 5 4 5 6 1 10 6 15 10 7 4 16

Use of Hygiene rinser - - - - - + - + - - + - + - - -

Use of bleach - - - - - + + + + + + + + - + +

Washing temperature (°C)

40 60 60 90 60 60 60 60 40 60 60 60 60 60 60 60

Machine cleaning + + - - + + + - + + - + + + - +

Bertelmann et al., DGHM conference 2012

Impact factors on laundry hygiene

Nursery school # 1 2 3 4 5 7 8 9 12 13 16 17 18 21 23 28

Reduction factor before/after washing

0,3 9,7 1,1 12,8 6,5 11,0 5,2 0,1 1,6 3,3 9,0 23,0 1,2 28,5 7,5 1,2

Machine age (y) 15 2 15 7 5 4 5 6 1 10 6 15 10 7 4 16

Use of Hygiene rinser - - - - - + - + - - + - + - - -

Use of bleach - - - - - + + + + + + + + - + +

Washing temperature (°C)

40 60 60 90 60 60 60 60 40 60 60 60 60 60 60 60

Machine cleaning + + - - + + + - + + - + + + - +

Bertelmann et al., DGHM conference 2012

Impact factors on laundry hygiene

Nursery school # 1 2 3 4 5 7 8 9 12 13 16 17 18 21 23 28

Reduction factor before/after washing

0,3 9,7 1,1 12,8 6,5 11,0 5,2 0,1 1,6 3,3 9,0 23,0 1,2 28,5 7,5 1,2

Machine age (y) 15 2 15 7 5 4 5 6 1 10 6 15 10 7 4 16

Use of Hygiene rinser - - - - - + - + - - + - + - - -

Use of bleach - - - - - + + + + + + + + - + +

Washing temperature (°C)

40 60 60 90 60 60 60 60 40 60 60 60 60 60 60 60

Machine cleaning + + - - + + + - + + - + + + - +

Bertelmann et al., DGHM conference 2012

Impact factors on laundry hygiene

Nursery school # 1 2 3 4 5 7 8 9 12 13 16 17 18 21 23 28

Reduction factor before/after washing

0,3 9,7 1,1 12,8 6,5 11,0 5,2 0,1 1,6 3,3 9,0 23,0 1,2 28,5 7,5 1,2

Machine age (y) 15 2 15 7 5 4 5 6 1 10 6 15 10 7 4 16

Use of Hygiene rinser - - - - - + - + - - + - + - - -

Use of bleach - - - - - + + + + + + + + - + +

Washing temperature (°C)

40 60 60 90 60 60 60 60 40 60 60 60 60 60 60 60

Machine cleaning + + - - + + + - + + - + + + - +

Bertelmann et al., DGHM conference 2012

Impact factors on laundry hygiene

Nursery school # 1 2 3 4 5 7 8 9 12 13 16 17 18 21 23 28

Reduction factor before/after washing

0,3 9,7 1,1 12,8 6,5 11,0 5,2 0,1 1,6 3,3 9,0 23,0 1,2 28,5 7,5 1,2

Machine age (y) 15 2 15 7 5 4 5 6 1 10 6 15 10 7 4 16

Use of Hygiene rinser - - - - - + - + - - + - + - - -

Use of bleach - - - - - + + + + + + + + - + +

Washing temperature (°C)

40 60 60 90 60 60 60 60 40 60 60 60 60 60 60 60

Machine cleaning + + - - + + + - + + - + + + - +

Bertelmann et al., DGHM conference 2012

Analysis of Laundry in Nursery Homes cf

u /

100

cm

2

Before laundering

After laundering

After drying

Very low counts after tumble drying

Bertelmann et al., DGHM conference 2012

Do hygiene rinsers help?

Hygiene

+

Source: Forum Waschen

Do hygiene rinsers help?

Claim: Kill 99,9(99)% of germsSubstantiated via suspension tests

Source: Forum Waschen

Efficacy in the washing machine?

• Additional detergency effect

• Textile effect

• Different germs

• etc.

Powder detergent with hygiene rinser

30°C+PD 30°C+PD+HR 40°C+PD 40°C+PD+HR 60°C+PD 60°C+PD+HR0.0

20.0

40.0

60.0

80.0

100.0

18.8

100.0 99.0 100.0 98.8 100.0

% r

edu

ctio

n

Lucassen et al., Tenside, Surfactants, Detergents (2013)

Akimitsu et al.: Antimicrob Agents Chemother 1999;43:3042-3

Cross resistance between antibiotics and biocides

Cross-resistance

Lambert: Journal of Applied Microbiology 2004, 97, 699–711

Lambert et al.: Journal of Applied Microbiology 2001, 91, 972±984

Resistance profile vs. origin

TSI: Total Susceptibility Index

Anz

ahl

Klinische Isolate

# Is

olat

es

Clinical Isolates

Clinical isolates are more resistance in general

Antibiotic resistance is predominately found in clinical isolates

Clinical environment fosters resistance

Lambert et al.: Journal of Applied Microbiology 2001, 91: 972-984

Does biocide use enhance antibiotic resistance?

Biocides at home?

Biocides at home?

Hygiene rinsers:only for special cases

Biocides at home?

Hygiene rinsers:only for special cases

http://londoncleaning-services.co.uk

Detergents with activated oxygen bleach ensure sufficient hygiene

Are we too clean? The hygiene hypothesis

Strachan (1989):

20th century rise in allergic diseases is related to lower incidence of infection in early childhood

Hygiene hypothesis: the consumer‘s view

„We need some bacteria to train our immune system“

„Too clean is harmful“

Hygiene hypothesis: the consumer‘s view

Hygiene hypothesis: the scientific view

Taken from: Smith et al.: The Hygiene Hypothesis and its implications for home hygiene, lifestyle and public health, IFH review 2012; based on: Rook G Clin Exper Immunol 2010; 160:70-79.

Old friends hypothesis (Graham Rook)

Microorganisms that were once abundant (but aren‘t any more) trained our immune system to be more tolerant:

- Lactobacilli- Saprophytic Mycobacteria- Parasitic worms

Are we too clean?

Cleaning does most probably not increase the risk for allergy and asthma

Are we too clean?

Cleaning does most probably not increase the risk for allergy and asthma

The targeted use of cleaning and antimicrobial products may help to reduce the risk for household-associated infections

Targeted Hygiene

Risk

Source: IFH

Thanks

Britta Brands, Angelina Eckert, Marlitt Honisch, Davina Lemm,

Ralf Lucassen, Nadine Merettig, Ramona Steiner

Thank you