HYGIENE IN THE 21st CENTURY

Sheri L. CarlinoDr. Charles P. Gerba

Department of Soil, Water and Environmental Science

University of ArizonaTucson, AZ

Life in the 21st Century Most of our time is spend indoors (80 - 90%) More people work in offices than ever before We travel more than ever before We spend less time cleaning than the last

generation (50% less than 50 years ago) We are less clean (e.g. laundry practices) We spend more time in public places We are more mobile and have more electronic

equipment (e.g. cell phones, ipods) We share more common surfaces (fomites) with

more people than ever before in history

Challenges in Infection Controlin the 21st Century

Infectious diseases are the 3rd leading cause of death in the United States today. They are 1st in the developing world.

Continued emergence and re-emergence of pathogens (SARS, MRSA, bird flu, etc)

A more susceptible population (aging population, cancer treatment) – 30 to 40% of

U. S. population at greater risk of serious illness and death)

Cleaning vs. HygieneCleaning is “the removal of

unwanted matter”Hygiene is “reducing the risks of

infection”Good hygiene had more impact

on human health than the development of vaccines and antibiotics

Did you know??

80% of all common infections (colds, flu, diarrhea) can be spread through the environment (air, water, food, fomites)

~800,000,000 cases of respiratory and enteric infections per year in the U.S.

Unmarried males experience one cold per year and unmarried women 1.3. Couples with school children experience 2.3 colds per year each. School children experience an average of 3.5 colds per year.

What are Fomites?

Inanimate objects involved in the spread of disease

Hand vs. Sneeze

Role of fomites in transmission of a disease

Sick person sneezes, coughs and pathogens falls on fomite or get aerosolized.

Pathogen falls on fomites e.g. phone, computer

Person picks up pathogen through contaminated fomite. Person touches nose or eyes

with Contaminated fingers and Becomes infected with pathogen.

Mouthing Events in Children (per hour)

81 times under two years42 times two thru five years

A child swallows the about of dirt on six kitchen floor tiles per day

Hand Contact in Adults

Adults touch their face 15.5 times per hour 2.5 eyes 5 nose 8 lip

Identifying Critical Control Points

Home/Work/Play/Shopping

Coliform Bacteria and E. coli

Coliform bacteria and E. coli are found in feces and their presence on surfaces indicates……………..contamination by feces and the potential presence of disease causing microorganisms

Germs at Home

Coliforms in the Home by Location

-2

-1

0

1

2

3

4

5

6

7

Geo

met

ric

mea

n pe

r cm

2 or

per

mL

Bath Sink

Kitchen Floor

Bath Counter

Bath Floor

Toilet Seat

KitchenSink

Sponge Cutting Board

The Importance of Cleaning Tools in the Spread of Germs

“Breeders”

“Spreaders”

• The kitchen is more heavily contaminated than the bathroom.

• Ordinary cleaning practices do little to reduce the microbial load.

• Risk of infection could be reduced by greater than 99.99% on cutting boards and kitchen counter- tops by use of hypochlorite cleaning products.

Germs at Home Summary

Bacteria on Shoes Shoes worn at least three months Total bacteria

13,600 to 8,000,000 sq cm Coliform bacteria

10 to 72,000 sq cm Present on 96% of shoes

E. coli Present on 27% of shoes

A Microbial Zoo Living on the Bottom of your Shoes

E. coli Aeromonas hydrophila Klebsiella pneumoniae Serratia marscesens Pseudomonas fluorescens Pseudomonas luteola Pantoea spp.

Shoes and Microbial Transport

Germ viewpoint –Shoes are made for walking

Left Shoe Right Shoe

1 ft 1,000 110

2 ft 400 10

3 ft 10 20

4 ft 240 90

5 ft 140 30

6 ft 100 640

66,000,000

Bacteria (105)

Virus (107)

68,000,000

23,000,000

27,000,000

21,000,000

15,000,000

61,000,000

27,000,000

11,000,000

17,000,000

4,200,000

2,600,000

Movement of organisms on shoes during walking – keeping in step with you

Another Brief Run Down of Bacteria Comparisons

(per square inch)200,000 – Carpeting49 –Toilet Seat1,686 Kitchen counter top2,546 Kitchen tile floor - home18,025 Bathroom floor - home

Vacuum Cleaners – Meals on Wheels for Bacteria

Concentrate bacteria and food in one place

E. coli detected on 50% of brushes from homes

Bag less: E. coli and Salmonella growth in collection container

Move bacteria and virus around

Why Do Shoes, Carpet and Vacuums Matter?

Exposure from Laundry

Changes in practices in the U.S

Hot water used only 5% of the time. Most use cold water

Only 12 minute wash Dry for only 3 minutes

Feces in the Laundry

Average pair of underwear contains 0.1 grams of feces (1/2 a Southwest Airlines peanut)

Salmonella 1010 per gram of feces

29

Hospital Scrubs

Total Bacteria

Type of scrub Number of

garments Average CFU/sq

cm

Unwashed hospital 18 180

Home- laundered 26 143

Hospital- laundered 20 4

Hospital Cafeterias

Bacteria isolated from tables MRSA C. difficile Enterococcus E. coli coliforms

31

Household Bath Hand Towels(442 towels tested)

HPC Bacteria Coliforms E. coli

Average 9.2E+08 3.9E+05 1.1E+04

Dayca

re

Playg

rounds

Bus tra

vel

Park

Gym

Theate

rPool

Resta

urant

Work

Doctor's

offi

ce0

5

10

15

20

25

30

35

40

45

5046

3635

2928

26

14 14

1110

% S

urf

ac

es

Po

sit

ive

Environments Most Contaminated With Body

Fluids

52

OCCURRENCE OF COLIFORMS (%) IN YOUR DENTIST OFFICE

64

70

0

0

63

76

67

18

53

50 22

4

OCCURRENCE OF E. COLI (%) IN YOUR DENTIST OFFICE

20

25

48

7

25

Microbiology of Automobiles

Dash board has the most germs followed by drink and change holders

Most bacteria detected in cars was Florida

Most molds in cars was detected in Chicago

Bacteria in Offices

Men Women0

200

400

600

800

1000

1200

Comparison of Bacteria in Men vs Women Offices

HP

C C

FU

/4 s

q in

Ave

rag

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Comparison of Offices that Use Disinfectant versus Offices that Don't Use Disinfectant

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

Don't Use Disinfectant Use Disinfectant

Ave

rage

Bac

teri

a

Impact of Wiping Table Top in Restaurants with Cleaning Cloths

Germs at School

Germiest Office Occupations

#1 Elementary School Teachers#2 Accountants#3 Bankers#10 Lawyers

Average Toilet Seat

Cafeteria Table Computer Mouse Desk1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+074.77E+06

1.70E+068.60E+05

Top Three Contaminated Sites in All Schools

To

tal B

acte

ria/

app

roxi

mat

e 10

0 cm

sq

School Study Grade K thru 12

Classrooms

Areas most contaminated with bacteria Pencil sharpener Student desk top Computer Sink in classroom

Viruses isolated Influenza Norovirus Parainfluenza

Impact of Disinfectant Wipes on Absenteeism -Seattle

Study Two school semesters 3rd and 4th graders

Intervention Children’s desk wiped with a disinfectant wipe

at the end of each school day Results

50% reduction in absenteeism

The Curse of the Cruise Ships

Detection of Noroviruses on Fomites –University of Arizona

Winter of 2008 Norovirus most commonly isolated on

• Desk tops (20%) Libraries Dorm rooms

• Vending machines buttons (5%)

Shopping with Germs

Coliform Bacteria in Reuseable Grocery Shopping Bags

51%Coliforms49% Yes

No

Reusable Shopping Bags

E. coli detected in 10% of the bags

Are Food Groups Separated?

25%

75%

Different Bags for Meats & Vegetables

Yes No

Grocery Store Touch Screens(self service)

100% contain bacteria (average 13,000)

Bacteria isolated MRSA E. coli Klebsiella oxytoca Coliform bacteria

(65%)

E. coli Isolation from Shopping Carts

Maine 80% Atlanta 79% Chicago 70% Tucson 0% Los Angeles 10%

Recent study has associated Salmonella and Campylobacter infections in children and placement in shopping carts

Going to the Toilet with Germs

Everybody uses the toilet

Average time in the aircraft restroom for adults

Men 106 seconds

Women 154 seconds

Aerosols are Produced during Toilet Flushing

Fecal bacteria and viruses are ejected from the toilet during flushing.

The droplets settle out in the restroom contaminating the restroom with fecal microorganisms

Commodeograph Water sensitive paper held over toilet seat when

flushed. Purple spots represent water droplets.

E.coli Detected in Droplets

Perti dishes held over toilet when flushed.

Dark spots are colonies of E. coli.

Refillable Liquid Bulk Soap Dispensers

25% are contaminated with millions of bacteria per milliliter

Coliform bacteria was found in 22% of samples

No bacterial contamination was found

in soap dispensed from

sealed systems

No bacterial contamination was found in soap dispensed from sealed systems

Traveling with Germs

Bus Travel increases Risk of Respiratory Infections

The more you ride a bus the more likely you will get a cold (6 times more likely)

Troko et al 2011 BMC Infectious Diseases

Seat – Bacteria/mold growing on Petri Dish

Airplane Trays MRSA – positive on

four different flights Norovirus isolated on

one flight

Vehicle Bacteria per 100 sq. cm.

CommuterTrain

117,000

Bus 83,176

Airplane 3,127

Family Car 5,220

Toilet Seat 186

ANOTHER COMPARISON TO THE TOILET SEAT!!!

Virus Spread between Hotel Rooms

Virus added to one person hand or bathroom counter top

Sample next series of rooms after maids clean and conference room at end of day, tested for virus.

Conference attendees hands

Results Virus detected

Next four rooms cleaned by the maid On surfaces (table tops) in the conference

room On 1/3 of the conference attendees hands On the coffee pot handle

of the breakfast area

Occurrence of fecal bacteria on the hand (United States)

Preparing a meal Greatest

Children after playing

Doing the laundry Least

Person exiting a toilet

Hand WashingTucson, Arizona

95% of people say they wash their hands after using a public washroom67% actually wash their hands

33% of those use soap 16% really wash long enough

Stopping the Spread of Germs

Reducing Risk of Infection from Fomites

Hand washing 30 to 50 % reduction in illness

Alcohol gel sanitizers 30 to 50% reduction Disinfection of fomite surfaces 50% reduction Use of bleach and hot water in laundering reduces risk of transmission

How fast does a virus move inan office building?

Added a virus to the entrance door handle of an office building with 80 persons

Collect samples after 4 and 7 hours from fomites and hands

First place virus detected is the

coffee break room

Virus detection on office workers hands/fomites after times indicated

Results

• The number of people with viruses on their hands was reduced in half (50%). The occurrence of viruses in communal work areas was reduced by more than 80% after four hours and by 70%-100% after seven hours

Hand sanitizers

Just as good as hand washing for bacteria and viruses. New formulations more active against norovirus.

However, not effective against spores like C. difficile.

Proper hand washing is effective in removal of spores.

UV light at the Tap

Point of dispense purification keeps the tap free from contamination

Antimicrobials Disinfectants

Chlorine• In use for more than 100 years• Wastewater treatment plant in Tucson, AZ uses more

chlorine in one day than a household uses in 10,000 years• Usually >99.999% reduction in target organisms

Quats• In use for more than 70 years

Some increase in tolerance by some bacteria, but still effective at normal use applications

Sanitizers Usually >99.9% of target organisms

The FutureSelf-Sanitizing Surfaces

Copper Silver Titanium Dioxide

Summary Fomites will continue play a major role in

disease transmission now and into the future

Good hygiene is not cleaning more, but smarter with a targeted use of disinfectants and cleaning tools

Germ exposure is more likely increasing not decreasing

No long term immunity for common infections

PROPER HANDWASHING

Questions?