Environmental Sampling for Infection Control Where, Why and How

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Environmental Sampling for Infection Control
!?!Where, Why and How

• Jennifer Block, Ph.D.
• Block Environmental Services, Inc.

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CDC/HICPAC Guidelines

• Do not conduct random, undirected, microbiologic
  sampling of air, water or environmental surfaces
  in health care facilities (270,343). (Section
  IA)

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CDC/HICPAC Guidelines

• Do not conduct random, undirected, microbiologic
  sampling of air, water or environmental surfaces
  in health care facilities (270,343).

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CDC/HICPAC Guidelines

• Guidelines do not say that you should not conduct
  directed and planned sampling of the environment

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CDC/HICPAC Recommendations

• When indicated, conduct microbiologic sampling
  (Section IB)
• as part of an epidemiologic investigation
• hazardous environmental conditions
• detect contamination
• verify abatement

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CDC Recommendations

• Limit microbiologic sampling for quality
  assurance purposes to (Section IC)
• Monitoring of sterilization processes
• Water and dialysate in hemodialysis units
• Short term evaluation of
• The impact of IC measures
• Changes in IC protocols

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Environmental Sampling

• Difficult and problematic
• No baselines, no acceptable ranges
• Few protocols for conducting planned, directed
  environmental studies in health care settings

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Where, Why and How
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Where?

• Air
• Water
• Surface

• OR
• ICU
• Doctors Office
• etc

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Why?

• Outbreak investigation
• Surveillance following outbreak
• Construction, renovation, repair
• Water intrusion
• Restoration
• Change in HVAC system, filter change
• Employee complaints, workers comp

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Employee Complaints

• Dust
• VOCs, sVOCs, metals
• Mold and pollen

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Air What to sample for

• Fungi and pollen
• Bacteria
• Dust, Asbestos
• VOCs, metals, others
• Endotoxin

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Air Where to Sample

• Location
• Operating Room
• Protective Environment

• Zone
• Breathing zone
• 4 feet off the ground
• Above the incision site of the patient during
  surgery
• Near air vents

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Air How to Sample for Mold, Pollen and Dust

• Non-viable spore trap samples
• Cassettes
• High volume vacuum pump

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Air How to Sample for Viable Mold and Bacteria

• Viable Sampling
• Active
• Surface Air Sampler (SAS)
• Anderson Air Sampler
• Growth media
• Passive
• Settle Plates

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Growth Media

• Fungi
• Malt Extract Agar (MEA)
• Non-selective, general media
• Dichloran Glycerol (DG18)
• Xerophilic fungi (Cryptococcus, Candida)
• Cellulose or Rose Bengal
• Slow growing (Stachybotrys)
• Bacteria
• Tryptic Soy Agar (TSA)
• Mesophilic, thermophilic actinomycetes
• Mcconkey Agar (MAC)
• Aerobic gram negative (Klebsiella)
• R2A (Reasoners)
• Heterotrophic Hemodialysis fluids (Pseudomonas)

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Air How to Sample for Chemicals

• VOCs, Formaldehyde, Ozone, Endotoxin, Benzene

Active
Passive
Sorbent Tubes
SUMA Canister
Flux Chamber
Photo Ionization Detector
Tedlar Bags
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Water What to Sample for

• Legionella spp.
• E. Coli
• Other microbes specific to outbreak
• Rhodococcus
• Pseudomonas
• Chemicals

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Water Where to Sample

• Sinks, Showers and Faucets
• Water baths
• Aerosolized water sources
• Ice machines
• Dialysis water and Dialysate
• Cooling towers and evaporative condensers

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Water How to Sample for Microbes

• Potable, non-potable
• Dip Slides
• Sterile collection container
• Holding time, Preservation (Temperature?) (Ice?)
• For Legionella
• 1Liter, 250ml
• First draw, second draw
• Swab biofilm

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Surfaces What to Sample For

• Fungi
• Bacteria

• Dust, Asbestos
• Metals
• Endotoxin

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Surface Where to Sample

• Soft
• Hard
• Porous
• Smooth

• Counters, walls, floors
• Bed railings
• Surgical Instruments
• Clothing
• Sharps containers

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Surface How to Sample

• Hard, smooth surfaces
• RODAC plates
• Dip Slides
• Tape
• Soft, porous surfaces
• Swab
• Tape

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Case Study IPlanned, Directed Sampling

• Why Sample?
• CABG SSI outbreak
• Rhodococcus 4 of 7 SSI cultures
• Gram Positive, bacillary aerobic actinomycete
• Found in soil, fresh water, sewage and feces

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Case Study I Planned, Directed Sampling

• Where to Sample?
• 4 of 7 SSI resulted from surgeries performed in
  the same OR
• 3 of 4 cases - by Surgeon X
• Fisher Exact Test Not Significant
• 4 of 4 cases - with Nurse A
• Fisher Exact Test Significant

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Case Study I Planned, Directed Sampling

• Where to Sample?
• Clotting Time Tests performed by Nurse A
• Test tube and nurses hand wet with water from
  water bath
• Sample water from water bath
• Positive culture for Rhodococcus
• Sample the air in the OR during surgeries
  performed with Nurse A present
• Positive cultures for Rhodococcus with highest
  CFUs per plate on samples collected in the area
  around the water bath

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Case Study I Planned, Directed Sampling

• Data Interpretation
• Rhodococcus growth in the water bath contaminated
  the hands of the nurse
• Contamination was passed to the patient
• nurses hands
• aerosolization from the water bath

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Case Study I Planned, Directed Sampling

• Recommendations
• Change protocol for Clotting Time Test to prevent
  hand wetting
• Change water bath policy to prevent growth of
  microbes

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Case Study 2Random, Undirected Sampling

• Why Sample?
• Contamination of environmental surfaces and air
  in the Biotechnology laboratory
• Organisms used for research
• Lysteria, E. coli, Salmonella, Bacillus
• Environmental contaminants
• Employee health
• Quality Assurance

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Case Study 2 Random, Undirected Sampling

• Where to Sample?
• Three large research labs connected by one main
  corridor
• Ice machine room
• Offices
• Molecular bio and biochem machines
• Incubators, water baths, refrigerators

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Case Study 2 Random, Undirected Sampling
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Case Study 2 Random, Undirected Sampling
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Case Study 2 Random, Undirected Sampling

• Data Interpretation
• All contaminants were environmental
• Employee hands
• Recommendations
• Better housekeeping
• Hand Hygiene
• Follow Up
• Cleaned and disinfected
• Re-sampled to establish baseline
• Monitoring program

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Case Study 3A Lesson in Futility

• Why Sample?
• Outpatient Dialysis Center
• Slow, ongoing leak from dialysis waste line
• Discovered fungal growth on sheetrock
• Patient and Employee Health
• Remedial Actions

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Case Study 3A Lesson in Futility

• Where to Sample
• Air
• At the source of the leak
• Distal from the leak at the Nurses station
• Surface
• Sheetrock
• Floor

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Case Study 3A Lesson in Futility

• What to Sample for
• Fungi Visibly growing on the wall
• Bacteria
• Total Bacteria airborne exposure
• E. coli
• Biohazard
• Waste disposal
• Remediation costs

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Case Study 3A Lesson in Futility

• Results
• Air
• Fungi
• Penicillium/Aspergillus spores 2,000 spores/m3
• Viable Penicillium 1,450 cfu
• Viable Aspergillus 1,952 cfu
• Bacteria
• Within normal levels and less than the outside
• No detectable coliforms

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Case Study 3A Lesson in Futility

• Results
• Surface
• Fungi
• Heavy growth of Penicillium and Aspergillus
• Bacteria
• Positive for coliforms and E.coli

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Case Study 3A Lesson in Futility

• Recommendations
• Cease the use of four dialysis stations in the
  area of the contamination
• Contain the contamination
• Remediate the contaminated area

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Case Study 3A Lesson in Futility

• Futility
• Facility management did not stop using the
  stations in the area of the contamination
• Did not contain the contaminated area
• Did not remediate
• The facility closed three weeks later.

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• Please share your experiences with environmental
  sampling!
• Good and Bad

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Acknowledgements

• Block Environmental Services, Inc
• Dave Block, Ph.D. Toxicologist
• Ron Block, Ph.D. Toxicologist
• Mari Block, RN
• Louise White, B.S. Microbiologist
• Holly Deily, B.S. Biologist