Keeping Out of Touch: The Role of High Touch Surfaces in Home and - - PowerPoint PPT Presentation

Keeping Out of Touch: The Role of High Touch Surfaces in Home and Community Settings and the Implications for Cleaning and Disinfection

Elizabeth Scott Simmons College, Boston Simmons Center for Hygiene and Health in Home and Community. International Forum on Home Hygiene (IFH) www.ifh-homehygiene.org

Historical Perspective

• The Morning

Gossip. George Cruikshank (1792-1878)

• www.viewima

ges.com

The Age of the Sanitary Reformers

• 1842 Report on the Sanitary

Conditions of the Laboring Populations of Great Britain (Edwin Chadwick)

• ‘Miasma’ theory of disease
• Florence Nightingale. 1859

Notes on Nursing

• Essentials for healthy home:

Pure air, pure water, efficient drainage, cleanliness, light

New York Council of Hygiene and Public Health 1864

• 1865 report on the sanitary

condition of NYC

• Metropolitan Board of Health
• 1890’s: reductions in urban
• utbreaks of typhoid & cholera

due to improvements in sanitation, water supply & street cleanliness

Late 20th Century

• Latter half of the 20th century – focus on health

care settings.

• “Infectious disease is beaten!”
• Environment played little role in endemic

transmission of healthcare-associated infections

• Societal changes: working women, urbanization,

travel, removal of household topics from school curricula , globalization of food supply, grouping

• f susceptibles.

Today……..

• Infectious disease burden
• Role of contaminated surfaces in hospitals

for endemic/epidemic transmission of C difficile, VRE, MRSA, A baumanii, Ps aeruginosa and norovirus

• Improved environmental decontamination

contributes to control

(Otter et al 2011 Infect Control Hosp Epidemiol)

Why home and community settings?

• Growing immuno-compromised population

in the community.

• Emerging pathogens
• Antibiotic resistance
• Home-care nursing
• Grouping of susceptible individuals
• Declining support for surface cleaning/

hygiene practices

Microbial ecology vs microbial risk

• Inanimate surfaces are contaminated!
• What is the microbial ecology of the indoor

environment?

• Snapshots vs temporal data
• Sampling techniques: ATP vs lab culture vs

molecular

• Clinical vs non-clinical settings
• “Germs”: “good germs” - “bad germs”
• Many representatives of human flora,
• pportunistic pathogens and some pathogens.

Bacterial contamination on planes

(McManus & Kelley 2005 J.Appl Micro)

• Frequently touched surfaces
• DNA sequencing and BLAST analysis to identify

sequences in Genbank.

• Bacterial diversity highest on lavatory surfaces including

door handles, toilet handles and sink faucets.

• Detected 58 different bacterial genera
• Most frequently observed species came from 5 genera

commonly associated with humans: Streptococcus, Staphylococcus,Corynebacterium, Proprionibacterium and Kocuria.

• “ Conclusions: The results show that there is a large

diversity of bacterial contamination planes, including

• rganisms known to be opportunistic pathogens”

Surfaces in home and community settings

• Complex & varied situations
• What is the risk?
• Setting: e.g. office vs daycare vs home
• Occupants & activities
• Type and rate & source of contamination
• Type of surface
• What is the likelihood of contact with a

surface? >>high touch surfaces

Criteria for infection risk associated with surfaces.

Reference: Block, 5th ed. 2001

Community – based infections linked to high touch surfaces

Infectious Gastrointestinal Disease

• Common but underreported
• Up to 50% of transmission person-to-person
• Surface involvement
• Norovirus, Rotavirus, Campylobacter
• Foodborne: 48 million cases of foodborne

illness/year USA

• >40% of reported foodborne outbreaks occur at

home

Skin Infections

• Common but under- reported
• Direct and indirect transfer involving

surfaces

• CA-MRSA
• San Francisco study: 85% of infections
• ccurred outside of healthcare (Liu et al. 2008)

Acute respiratory infections

• Adults: 1.5-3 infections/year
• Children under 5: 3.5-5 infections/year
• Loss of productivity & economic burden
• Cold viruses, 80% rhinovirus.
• Influenza epidemics USA: 36,000 deaths,

114,000 hospitalizations.

• Role of hands and surfaces in

transmission of influenza.

The transmission equation for hands and high touch surfaces

temporary reservoir

humans pets raw foods

Pathogen transfer rates from hand contact surfaces to hands

• Highly variable
• Species and strain specific
• Highest from non-porous surfaces

Wet Reservoir Sites

• E.coli & fecal coliforms
• Salmonella
• Shigella sonnei
• Norovirus
• Risk is relatively low

except during outbreaks

• f enteric infection

Reservoir -disseminator sites

• E.coli & other

coliforms

• Salmonella
• Listeria
• MRSA
• Fungal contaminants
• Risk of cross-

contamination to

• ther surfaces is

constant

Hand & Food Contact Surfaces

• E.coli & coliforms (fecals)
• Cytomegaolvirus &

rotavirus in daycare

• MRSA: home, athletic &

LTCF

• Vancomycin-resistant

enterococci (VRE) in LTCF

• Rhinovirus & influenza

virus in offices.

• Risk is variable but

constant

Floors, carpets, athletic mats & soft furnishings

• C. difficile spores, VRE, Group A

streptococci & MRSA in LTCF’s

• MRSA in homes and athletic facilities
• Enterics (salmonella, rotavirus etc) in

daycare

• Norovirus – hotels and cruise ships etc.
• Risk: for groupings of vulnerables & some

specific activities

Examples of pathogen transfer between surfaces and hands.

• Campylobacter & Salmonella in kitchens: hands,

cutting boards, rags (Cogan et al 1999 Ltts Appl Micro )

• Polio virus following vaccination of infants found
• n 13% of hand contact surfaces (Curtis et al 2003 IntJ

Enviro Hlth)

• Rhinovirus on 35% hand contact surfaces

sampled in hotel rooms (Winther et al 2007 J Med Virology)

• CA-MRSA average transmission to pigskin from

hand contact fomites was 62% of bacteria recovered directly from the fomite (Desai et al 2011 AJIC)

Pathogen survival on inanimate surfaces

• Most Gram +ve bacteria: months on dry

surfaces

• CA-MRSA: weeks to months on vinyl and

plastic fomites (Desai et al 2011. AJIC)

• Many Gram –ve bacteria: months
• Most respiratory viruses: few days
• GI tract viruses, e.g. rotavirus: up to 2

months

• (Kramer et al. 2006 BMC Infectious Disease)

SURFACE S.aureus % MRSA % SURFACE S.aureus% MRSA %

Sponge/cloth n= 33 30 3 Toilet seat 14 Dish towel n=31 27 7 Counter top n=33 12 Sink 23 3 Door handle n=34 12 3 Drain 20 3 Faucet handle 11 3 Floor n=34 18 Toilet floor 11 Phone n=34 15 Light switch n=34 9 Table top 14 Flush Handle n=34 3 Counter top n=34 12 3 Child training potty n=10 ‘Fridge handle 11 Other Faucet handle 12 6 Child toy 34 Microwave touch n=34 7 Infant high chair tray n=26 29 5 Garbage bin n=34 6 3 Infant changing mat n=24 27 Chopping board n=32 Pet food dish 15 3 Bathroom TV remote n=34 12 Tub 26 3 Phone n=22 13 Sink 17 3 Computer Mouse n=31 10 Computer Keyboard n=32 3 Toilet bowl n=34 15

Household Surfaces with MRSA

(Scott et al 2009, AJIC)

[

Surfaces Hand contact vs Non handcontact Wet (W) or Dry (D) surface Dish towel Hand D Kitchen countertop Hand D Kitchen faucet handle Hand D Sponge Hand W Bathroom faucet handle Hand D Bathroom door handle Hand D Infant highchair Hand D Pet food dish Hand D Bathroom sink Hand W Bathroom tub Hand/skin W Kitchen sink Hand W Kitchen drain Non hand W Garbage bin Non hand D

Breaking news

• Carriage of methicillin-resistant

staphylococci by healthy companion animals in US (Davis et al 2014 Lttrs in Appl Micro)

• Are community environmental surfaces

near hospitals reservoirs for gram- negative nosocomial pathogens? (Rose et al

AJIC April 2014)

Conclusions

• Complex indoor environments
• At risk populations
• Community-based infections
• Pathogens survive on, and transmitted to/from

surfaces, especially high touch surfaces

• Merits further studies
• Implications for where to focus our efforts to

interrupt chain of transmission: hands and high touch surfaces.

• Evidence-based hygiene practices