The Art and Science of Handwashing. Handwashing 80% of common infections spread by hands Most effective way of preventing the spread of respiratory tract.

The Art and Science of Handwashing

Handwashing

80% of common infections spread by hands

Most effective way of preventing the spread

of respiratory tract infections

Handwashing

1822 - Labarraque – French pharmacist

chloride solutions

published paper in 1825

1843 - Oliver Wendell Holmes

decrease in puerperal fever

1846 - Ignaz Semmelweis

chlorine/nail brush

reduced deaths in obstetric wards

20% 1%

Improved Patient Outcomes Associated with Proper Hand

Hygiene

Ignaz Philipp Semmelweis

(1818-65)

Chlorinated lime hand antisepsis

Puerperal fever19th century physicians

miasmas – bad airSemmelweis

incontrovertible proofrefused to publish logic behind his theoryphysician practice did not change

Joseph Lister 20 years laterpublished in Lancet

Handwashing1975, 1985 CDC

Handwashing guidelines1988, 1995APIC

First to recommend alcohol based hand rubs1995,1996HICPAC

Antimicrobial soap/alcohol based agents2002HICPAC/SHEA/APIC/IDSA

Guidelines for Hand Hygiene in Health-Care

Health-Care Associated Infections

USA2 million infections/year 90,000 deaths $ 4.5 billion / year 1/3 preventable

Resident Flora

S. epidermidis / Micrococci / DiphtheroidsSurvive and multiply on skinThroughout skin layersCultured repeatedlyLow virulenceFingernails / crevices / hair follicles / sebaceous

glandsNot easily removed by scrubbing

Transient Flora

E. coli, Klebsiella, Streptococci, Pseudomonas +/- S. aureus

Usually survive less than 24 hours

Do not multiply

Can be easily removed by handwashing

How easy is it to transmit germs?

.

103 – 105 bacteria to hands

Touching patient shoulder

Measuring blood pressureDuckro AN et al. Arch Int Med 2005;165(3):302-7.

Rings:Trick et al,

CID 2003:36

10 fold higher median skin organism count

stepwise increase with number of rings worn

Gloves:

1) reduce transmission from patient to HCW

2) prevent transmission of HCW flora to patient

3) reduce transient contamination of HCW hands

Impact of Hand Hygiene on Hospital Infections

Year Author Setting Impact on Infection Rates

1977 Casewell adult ICU Klebsiella decreased1982 Maki adult ICU decreased 1984 Massanari adult ICU decreased 1990 Simmons adult ICU no effect1992 Doebbeling adult ICU decreased 1994 Webster NICU MRSA eliminated1995 Zafar nursery MRSA eliminated1999 Pittet hospital MRSA decreased

Source: Pittet D: Emerg Infect Dis 2001;7:234-240

General hospital hand hygiene campaign

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

1993 1994 1995 1996 1997 1998Year

new MRSA per 100

admissions

0

2

4

6

8

10

12

14

16

18

20

Nosocomial infections per

100 admissions

MRSA

Nosocomial infections

Pittet, Lancet 2000

Post-surgical acute care unit hand hygiene program

Pre-intervention

Post-intervention

Total infections per 100 patients 12.7 8.9

Total infections per 1000 pt-days 6.2 5.0

BSI per 1000 patient days 9.3 8.9

RTI per 1000 patient days 6.2 3.8

Swoboda Crit Care Med; 2004:32:358

Handwashing ComplianceIntensive Care Units

Profession% Handwashing

University Private

Physicians 28 14

Nurses 43 28

Respiratory therapists 76 48

Radiology technicians 44 25

Albert RK, Condie F. NEJM 1981;304(24):1465-6

Lack of knowledge

Nursing students at some schools in Ontario:• no classroom training in infection

prevention

SARS outbreak:• fewer than 60% of quarantined HCWs

accurately identified why they were being quarantined

How Dirty Are Things?

University of Arizona study:

TucsonChicago

San FranciscoTampa

Location Contamination (%)

Playground 44

Bus Rails 35

Public Restrooms 25

Pens (shared) 16

Vending Machines 14

Public phones* 13

*home phones more contaminated

How easy is it to transmit germs?

10 million E. coli 0157.H7

Patting contaminated ground beefWachtel MR et al. J Food Prot 2003;66(7):1176-83.

103 – 105 bacteria to hands

Touching patient shoulder

Measuring blood pressureHayden MK et al. ICCAC 2001, abstract K-1334

American Society for MicrobiologySurvey and Observational Study

StudyYear

Say they wash*

Actually wash*

Women Men

20008,000 people

5 cities95% 75% 58%

20056,336 people

4 cities91% 90% 75%

NOTE: 2003 Post SARS @ Toronto Airport – 96% actually washed

*After using public washroom

Travellers

Percent who did NOT wash hands

JFK NYC – 29%

San Francisco – 26%

Chicago – 26%

Miami – 26%

Dallas Forth Worth -19%

Toronto – 4%

School

22 million school days lost annually to common cold (CDC 1996)

Am J Infect Control 2000school with handwashing policy

2.42 days missed/student/year

school not using proper hand hygiene

3.02 days missed/student/year

Hand hygiene products

Regular soap

Antibacterial x

Antiseptic

Alcohol based

Hand hygiene products

ProductAntimicrobial

ActivitySustained Activity

Potential for Resistance

Skin Shedding

Soap + none none +++

Antibacterial* Intermittent ++ ++ ++ ++

Continuous +++ +++ +++ +++

Alcohol +++ none none +

Adapted from CID 1999;29:1287-94

* triclosan, hexachlorophene, chlorhexidine gluconate

Antibacterial soaps

Not needed in the community

Not needed routinely in hospital

Promote antibacterial resistance

Antibacterial soaps

Levy S

S. aureus resistance to triclosan

Schweizer et al AAC. 2001,45:428-432

exposure of P. aeruginosa to Triclosan MIC to tetracycline, erythromycin 500X MIC to ciprofloxacin 94X

Triclosan: mechanism of action

Triclosan:

Inhibits fatty acid synthesis (fab I gene)

Target = enoyl reductase

E. coli mutants easily selected with exposure

S. pneumoniae, Enterococcus, lack fab I and are not

susceptible

Yazhankhah SP, et al. Microb Drug Resist 2006;12(2):83-90.

Triclosan and antibiotic resistance

Resistance to triclosan:Mutation in fab I gene

• fab I potential site for development of new antibiotics

Activation / upregulation of efflux pumps • Multi-drug efflux = cross resistance

Other resistance mechanisms not well understoodCo-resistance to other antibiotics

Thorrold CA, et al.Int J Food Microbiol 2007;113(3):315-20. Seaman PF, et al. J Antimicrob Chemother 2007;59(1):43-50.

Akimitsu et al.

Antimicrob Agents Chemother 1999;43:3042-3

Methicillin Resistant S. aureus (MRSA):

Link:

antimicrobial soap and community acquired MRSA

Antibacterial Household Products: Cause for Concern

Stuart B. LevyEmerging Infectious Diseases, 2001;7(3):512-515

Antimicrobial Resistance

Allergy Link

Cause for Concern

Allergy Link• Too much hygiene and increased allergy

children on farms < allergies than children in citiesBraun-Fahrlander. Clin Exp Allergy 1999;29:28-34

• Excessive hygiene may interfere with immune system maturation of T helper cells

• eliminate stimulation from commensal microflora• immune system not confronted with enough antigens

Folkerts et al. Immunol Today 2000;21:118-20

Antibacterial products

> 700 different products

toothbrushes

plastic containers/chopsticks

sheets, towels, beds

window cleaner

No demonstrated health benefit in the household

BacteriaGood or Bad Germs?

60% of earth biomass

2-3 billion microbial species

< 0.5% have been identified

Preceded plants / animals

> 3 billion years

Essential to life

Both internal / external environments

Antibacterial soaps

Not needed in the community

Not needed routinely in hospital

No enhanced activity against viruses, fungi

Promote antibacterial resistance

Antiseptic soaps

Not needed in the community for general hand hygiene

Have a role in hospital setting

May promote antibacterial resistance

Alcohol Based Waterless Agents

Advantages - no water required- fast to use Voss, Widmer. Infect Control Hosp Epidemiol 1997

- less drying time- less skin shedding Meers, Yeo. J Hyg 1978 - broad spectrum efficacy

kill bacteria (fungi, viruses

- do not promote resistance

Alcohol Based Waterless Agents

Disadvantages:

not effective in presence of organic material will kill resident flora

SHOULD NOT REPLACE SOAP AND WATERSHOULD NOT REPLACE SOAP AND WATER

When to Wash Hands

Before eating or preparing food

After using the toilet or helping a child use the toilet

Before and after diapering

After handling shared objects such as toys

After wiping your nose or helping a child wipe

his / her nose

Handwashing

Not long enough

average 9.5 seconds need 15-20 seconds

Use soap and water

(water alone does not get rid of germs)

Rub hands together for 20 seconds

Sing Twinkle, Twinkle Little Star Song

Rinse for 10 seconds

Dry with a towel

How to Wash Hands

Hand Drying

Removes 42% more germs than washing alone

Use towels and avoid sharing towels

Hot air dryers promote bacterial growth because hands are left warm and moist

Does Handwashing Work?

Ryan M. Health Naval Research Center, San Diego

Recruits ordered to wash hands at least 5 times /day

45% reduction in respiratory illness

Ryan MA et al. Am J Prev Med 2001;21(2):79-83

Lee M. Canadian Journal of Infection, Toronto

Nurses - at least 7 handwashing episodes/day

Decreased number of enteric / respiratory infections

Lee MB. Can J Infect Control 2000;19:89-91

Effect of Antibacterial Home Cleaning and Handwashing Products on Infectious Diseases

Larson et al Annals of Internal Medicine 2004

Randomized double blind clinical trial 238 inner city homes with at least 1 preschool aged child - NY

Conclusion

Antibacterial products did not reduce the risk for symptoms of viral infectious diseases in households of healthy people

fever/sore throat/runny nose/vomiting/diarrhea

The Effect of Hand Hygiene on Illness Rate Among Students in University Residence

HallsAJIC 2003;31:364-70

College dorms randomized :

Alcohol hand rubs in various locations vs. not.

Alcohol hand rub groups: 14.8% -39.9% reduction in respiratory illness

symptoms 43% fewer sick days

Effect of Handwashing on Child Health: A Randomised Controlled Trial

Squatter settlements in Karachi

50% reduction in pneumonia

53% reduction in diarrhea

34% reduction in impetigo

No difference between plain soap and antibacterial soap

Lancet 2005;366:225-233

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