Bactiquant Water Rapid Onsite Screening for Assessing Legionella

Report
Bactiquant Water
Rapid Onsite Screening
for Assessing
Legionella Risk
Presented by Lisa Rogers
“Legionellosis emerged
because of human
alteration of the
environment, since
Legionella species are
found in aquatic
environments, and
thrive in warm water
and warm, damp places,
such as cooling towers”
Legionella and the prevention of legionellosis, WHO 2007
World Wide
• Since 1976, 35 outbreaks reported 2-800 cases
– 11 in NA (US/CA)
– 14 in AUS/NZ
– 10 in Europe
• Sources
– 13 Cooling towers
– 5 each, Spas/hot tub, DHW, AC, and 4 unknowns
– Misc include potting mix, fountain, industrial systems
Year
City
Location
Cause
Cases
Fatality
rate
2012
Québec City,
Canada
Lower Québec City
Possibly cooling towers
180
7%
2012
Calp, Spain
AR Diamante Beach Hotel
Possibly solar water heating
system for spa and DHW
18
17%
2012
Scotland
SW of Edinburgh
Possibly cooling towers
99
3%
2012
Chicago,Illinois
JW Marriott Hotel
Decorative Lobby Fountain
10
30%
2012
Auckland, NZ
Unknown
Water Source and/or AC
11
9%
2012
Stoke-on-Trent, UK
Warehouse, Fenton
Hot tub
19
5%
2012
Pittsburgh, PA
VA Hospital
unknown
22
27%
2013
Queensland, AUS
Wesley Hospital
NYD, probably hot water system. 2
50%
2013
Memphis,TN
24-Hour Fitness
NYD probably pool or spa.
3
0%
2013
Milwaukee,WI
Not yet determined
Not yet determined, ongoing
20
2013
Reynoldsburg, OH
Wesley Ridge Retirement
Comm
Potable water system, ongoing
44
2013
Warstein,Germany
Warsteiner Brewery
Air conditioning, ongoing
165
2013
Florence, AL
Glenwood Nursing Home
Unknown, still under
investigation.
13
Concerns
• CDC estimates 8,000 to 18,000 people are hospitalized
each year in the U.S. Mortality rate is approximately 15%
• Legionella bacteria are found naturally in the environment
• French study found that L. pneumophila can travel
airborne at least 6 km from its source
• Norway study found high velocity, large drift & high
humidity in air scrubber… spread probably for >10 km
• WHO estimates the cost savings to implement preventive
plans is $1-3M USD per life saved. (1200 x 1M= $1.2B)
Ideal Water Conditions
•
•
•
•
•
•
Temperatures between 20° and 50°C (68° - 122°F)
Optimal growth range is stagnant water 35° - 46°C [95° - 115°F]
pH between 5.0 and 8.5
Available iron and copper
Sediment/scaling promote growth of commensal microflora
Other micro-organisms including algae, flavobacteria,
and Pseudomonas, which supply essential nutrients for growth
of Legionella or harbor the organism (amoebae, protozoa)
• Low biocide concentrations
Water Sampling Guidelines
Table III:7-1. COLONY FORMING UNITS (CFU) OF LEGIONELLA PER MILLILITER
Action
Cooling Tower
Domestic Water
Humidifier
1
100
10
1
2
1,000
100
10
Action 1: Prompt cleaning and/or biocide treatment of the system.
Action 2: Immediate cleaning and/or biocide treatment. Take prompt steps to prevent
employee exposure.
Source : OSHA, 1999
CDC recently testified that there is no safe level !
Current Sampling Strategy
Culture Plate Analysis
• 3-5 days for HPC
• 7-10 days for Legionella
• Planktonic, highly variable, overloading,
background interferences
PCR
• fast but expensive
How BQW can help
Rapid test can be
performed in 15-30 mins
Easy Sampling and
Analysis
EPA ETV verified
methodology
Enzyme substrate
Fluorescent compound released
+
Bacteria-enzyme
Principle Method
Why is Bactiquant Technology interesting ?
• Culture-independent technique
• Quantification of a naturally occuring hydrolase enzyme activity
present in bacteria
• High specificity to bacteria, little background interference
• Use of fluorescence technology = high sensitivity
• Concentration Step = increased sensitivity and significant reduction
in detection time
Laboratory Comparison BQW
HPC - DS6222 (cfu/ml)
10000000
1000000
100000
10000
1000
100
10
1
1
10
100
1000
10000
BactiQuant analysis result (fu/ml)
100000
1000000
EPA ETV Report Excerpt
Table 2: Linearity: BQ Value vs Concentration
Test
Organism
Concentration Range of
Range
Average BQ
(CFU/mL)
values
Slope
Lake Water
Indigenous
Bacteria
3.7 x 102 to 6.0
x 103
1542 to
15607
2.38
2243
0.9138
Lake Water
Indigenous
Bacteria without 1:5
dilution
3.7 x 102 to 3.0
x 103
1542 to
11106
3.55
739
0.9689
0.95
-136
0.9923
P. aeruginosa 8.7 x 102 to 8.0
868 to 7655
ATCC 27853
x 103
Source Battelle / US EPA -2011
Coefficient of
YDetermination
intercept
(R2)
EPA ETV Study Excerpt
High reproducibility
Adjusted Fluorescence (fu)
Test Iteration
8.0 x 103
CFU/mL
4.7 x 103
CFU/mL
2.1 x 103
CFU/mL
8.7 x 102
CFU/mL
1
11392
6128
2799
1249
2
12332
6074
2710
1247
3
11376
6012
2559
1297
4
11513
6508
2768
1437
5
11614
6256
2945
1375
Average
11645
6196
2756
1321
Standard
deviation
396
196
140
83
RSD (%)
3.4
3.2
5.1
6.3
Source Battelle / US EPA -2011
EPA ETV Report Excerpt
Table 3. Bactiquant®-test Repeatability and Inter-Assay Reproducibility
Test Iteration
BQV Fluorescence (flu)
Indigenous Bacteria from Lake
P. aeruginosa ATCC 27853
Water
(4.7 x 103 CFU/mL)
2
(3.7 x 10 CFU/mL)
Analyst 1
Analyst 2
Analyst 1
Analyst 2
Average
2363
2225
6888
6691
Standard
deviation
152
57
333
93
RSD (%)
6.4
2.6
4.8
1.4
RPD (%)
6.0
2.9
Table 3 summarizes the repeatability and inter-assay reproducibility results for Bactiquant®-test using two bacterial
cultures in water. Two different people analyzed 4 samples of each culture, using different fluorometers.
CASE STUDIES
7
6
5
4
BQ value 1000
3
BQ value 100
2
BQ value 10
BQ
Legionella
pneumophila
serotype 2-14
1
0
1
3
5
7
9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69
Critical care facility, Courtesy of Clinical Microbiology Institute, Viborg Hospital, Denmark
2006.
X-axis Sample No. (1-70)
Y-axis Log10(adjusted fluorescence) and Log10(cfu) Legionella pneumophila serotype 2-14
Australia Case Study
•
•
•
•
Wesley Hospital, Queensland: 2 cases, 1 death
5 Building, 560 bed facility
Heat Treatment for 2 weeks @ 70C ( 158F)
Over 3000 samples collected BQ, Legionella,
HPC
• 13 days to reopen, 29 days fully operational
• BQ used to screen, verify cleaning efficacy and
validate post treatment
Comparison between Pre-Treatment (Blue), and Post Treatement samples
collected on the 26/9 (Red) and the 30/9 (Green)
4500
4000
BQ Heterotrophic Microbial Equivalent^ (cfu/mL)
3500
3000
2500
Pre-Treatement
2000
Post Treatement (26/9)
Post Treatement (30/9)
1500
1000
500
0
104
110
114
135
226
226 Dirty 237A
237B
Room Number
285
315
316
609
L6
Endo Int
2
1600
1400
Mains water 1
1200
Mains water 2
BQ Equivalent cfu/ml
1000
800
600
400
200
0
25/09 11:00
26/09 12:00
26/09 13:00
26/09 14:30
26/09 16:00
26/09 17:00
26/09 18:30
Sample
30/09 12:00
30/09 13:30
30/09 14:30
30/09 16:30
30/09 18:00
“CETEC made use of the Bactiquant® water technology
for the rapid screening of total bacterial loading within the
potable water network. This technology allowed CETEC
in under an hour to obtain results superior to plate count
for the network. The ability to obtain rapid results as
compared to 4 to 10 day timeframe for conventional methods
presented significant time, logistical and financial savings.”
Excerpt from: The Australian Hospital Engineer, September 2013
New Studies
The Danish Health
Institute has started a two
year project now with
multiple sites looking at
pre-screening as well as
post treatment efficacy.
Hopefully, some results
from that study will be
forthcoming later this year.
Pros and Cons
•
•
•
•
•
Rapid onsite testing aids in identifying hotspots
Validate the efficacy of cleaning methods
Monitor for changes in system quickly
HPC nor BQW a perfect predictor of Legionella
Not a substitute for direct Legionella analysis
Do you have any questions?
THANK YOU FOR LISTENING!
Lisa Rogers
[email protected]
813-831-6511
www.mycometer.com
BOOTH ON AISLE 3000

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