Transcript Slide 1

Recreational Water Illnesses:
A 2011 Comprehensive Overview
Roy Vore, Ph.D., NSPF®I, CPO®
Vore & Associates LLC
[email protected]
Michael Lowry, NSPF®I, CPO®
Lowry and Associates
[email protected]
CIPHI Annual Educational Conference
June 26-29, 2011, Halifax, NS
(C) 2011 Vore & Associates
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Ways to guarantee zero outbreaks
of infections
1.
2.
Keep the pH below 2.0 or above 12.0
Never let anyone touch the water or
inhale the air above the water
Every other treatment options means there
is a risk of an RWI outbreak.
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Recreational water illnesses (RWIs)
can be transmitted in three ways
 Ingesting
 Contact
water
with water
 Air
If you are in or near a
pool or hot tub that
is contaminated you
will be exposed and
subject to infection
or illness.
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How many RWIs are there?
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Nobody really knows
Probably less than 5% of outbreaks are ever
recognized
Once recognized the outbreak must be reported to
local department of health
Only outbreaks that effect 2 or more people and occur
in a public facility are investigated
Thoroughness of the investigation varies greatly
The US Centers for Disease Control and Prevention
(the CDC) compiles summaries every two years
The summaries do not cover private homes
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The US Centers of Disease Control
and Prevention (the “CDC”) tracks Water Borne
Disease Outbreaks (WBDO)
 2005-6


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major reported RWIs
78 outbreaks
31 states and Guam
4,412 people
116 hospitalizations
5 death

Due to under-reporting the true
number is 10X to 100X higher
Minor RWIs are not reported!
This number is increasing every year.

http://www.cdc.gov/mmwr/pdf/ss/ss5709.pdf

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Recreational water illnesses:
a quick overview
Illness type
Causative
agent(s)
Frequency of
illness
Press
coverage
Gastrointestinal
Bacteria
Viruses
parasites
Rare
Very high
Dermal
Pseudomonas
Very common
Very low
Disinfection byproducts
Very common
Very low
Legionella
Rare
High
Disinfection byproducts
Common –
esp. indoors
Very low
Respiratory
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Recreational water illnesses:
Illness v. venues
Illness
Pools
Spas
Gastrointestinal
E coli O157:H7
Shigella
Norovirus
Hepatitis A
Cryptosporidium
Giardia
Minimal – most users do
not swallow enough water
for infection
Dermal
Ps. aeruginosa
Chloramines (DBPs)
Ps. aeruginosa
Bromamines (DBPs)
Respiratory
Chloramines (DBPs)
(indoor pools)
Legionella
Bromamines (DBPs)
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Recreational water illnesses:
Public vs. private venues
Pools
Spas
Public
facilities
Gastrointestinal
Dermal (Pseudomonas
Dermal (Pseudomonas
including hotels,
condos and
health clubs
& DBPs)
& DBPs)
Respiratory
Respiratory
(DBPs @ indoor pools)
(Legionella & DBPs @
indoor pools)
Residential
Dermal (Pseudomonas
Dermal (Pseudomonas
(private homes)
& DBPs)
& DBPs)
Respiratory
Respiratory
(DBPs @ indoor pools)
(Legionella & DBPs @
indoor pools)
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Gastrointestinal illness
 Why
only certain germs?
 Where do the bugs come from?
 How do you control them?
 What happens during an outbreak?
 How do you respond when something
goes wrong?
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The germs that gastrointestinal RWIs have
very, very low infective doses
Organism
E coli O157:H7
Dose that will
cause disease
10 cells
Norovirus
10 particles
Giardia
10 –100 cysts
Cryptosporidium
10 cysts
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Where do bugs that gastrointestinal
diseases come from?
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From swimmers!!!!
 The average person swallows 1 ounce of water for every
30 minutes of swimming
 Gastrointestinal illness is caused by swallowing food or
water that has contaminated with feces
 The average person also carries 0.14 grams of feces on
the rear end – babies carry more!
 Add up all the bodies and you get a fair amount of feces
 If a bather has an accident (formed or diarrhea) the
amount of feces in the water goes way, way up
 At some point the concentration rises above the
minimum for infection – and there is an outbreak
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US Gastrointestinal RWIs 1997-2006
Percent of outbreaks by pathogen
2.9%
Chlorine sensitive
6.7%
6.7%
8.7%
3.8%
2.9%
68.3%
E coli
Shigella
Norovirus
Other
Unidentified
Giardia
Cryptosporidium
Crypto is the only one
that is chlorine resistant
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Control of gastrointestinal illness
causing pathogens in pools
Group
Bacteria
Viruses
Parasites
Organism
Killed by chlorine?
E coli (including
O157:H7)
Shigella
Adenovirus
Norovirus
Giardia
Very quickly – all
bacteria killed in <1 min
@ 1 ppm FAC
Cryptosporidium
Quickly – probably <20
min @ 1 ppm FAC
Quickly - <45 min @ 1
ppm FAC
Killed by 20 ppm FAC
12.75 hours in absence
of CYA
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Gastrointestinal illness:
Cryptosporidium is the 800 pound
gorilla of RWIs
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The infective unit is built like a
basketball with two little larvae
inside the ball.
No combination of current
treatments will completely control
this germ in a timely manner.
Best prevention is to discourage
swimmers who have been ill
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Clinical definition of diarrhea: 3
incidents of diarrhea in a 24 hour period
People shed germs after recovering
Don’t swim for at least 7 days after a
clinical case of diarrhea
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Gastrointestinal illness
from pools and spas

Many germs that cause illness (including E coli, Shigella,
Norovirus, Adenovirus, and Giardia) are readily killed by
1 ppm of free chlorine
 The Centers for Disease Control and Prevention states
that between 1993-2006 one-third of all GI illness were
caused by these same chlorine sensitive germs.
 This means that if we are running our pools properly
one-third of these serious GI illnesses would disappear
today!
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Only one organism, Cryptosporidium, is highly resistant
to chlorine – it takes 20 ppm chlorine and 12.75 hours to
kill this one
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Gastrointestinal illness
A hypothetical case

A fecal accident happens in a 75,000 gallon pool
 Person is infected and releases 1 billion E. coli O157:H7
cells (it could also be 1 billion Crypto oocysts)
 Assume all fecal matter is uniformly mixed and none is
removed by filtration
 Every 30 ml (1 ounce) will contain 105.8 infective units –
30 ml is a small swallow of water
 Swallowing as little as 3 ml (0.1 ounce) will cause
diarrhea in sensitive individuals
 This amount of E coli O157:H7 can be fatal to
toddlers
 Imagine this in a 5000 gallon wading pool!
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What do you do when something
goes wrong?
 Base
treatment on the incident
 Assume the worse case scenario

What is the most difficult to kill germ that is
likely to be present?
 Treat

for worst case
If you kill the difficult germs all of the sensitive
germs will also be killed.
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Health threat assessment
Accident
Pathogens
Most
resistant
Treatment
Plan
Blood
HIV, Hepatitis B, All similar
Hepatitis C
None – pathogens not
spread through water
Vomit
E coli,
Norovirus,
Hepatitis A
Norovirus and
Hepatitis A
Formed Feces & Vomit
Response
Formed
feces
E coli, Giardia
Giardia
Formed Feces & Vomit
Response
Diarrhea
E coli, Shigella,
Norovirus,
Giardia, Crypto
Crypto
Diarrheal Accident
Response
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Formed Fecal Accident
and Vomit Response
1.
2.
3.
4.
5.
6.
6.
Clear and close pool at once
Scoop or net out feces – flush feces down toilet
Hold chlorine level at >2.0 ppm for 25 minutes
Maintain pH at 7.2-7.5 ppm
Filter continuously
Re-open pool
Soak net in bucket of chlorine (500 ppm FAC for 30
minutes)
7. Document each vomit and fecal accident by recording
date and time of the event, note whether formed stool
or diarrhea, and note the chlorine levels at the time or
observation of the event.
Check www.cdc.gov for latest information
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Diarrheal Accident Response
1. Close pool at once
2. Scoop or net out feces – flush material down toilet
3. Raise free chlorine to 20 ppm for 12.75 hours
4. Maintain pH at 7.2-7.5 ppm
5. Filter continuously
6. Backwash filter to sanitary sewer
7. De-chlorinate to 1 to 4 ppm free chlorine
8. Re-open pool
9. Soak net in bucket of chlorine (500 ppm FAC for 30 minutes)
10.Document each vomit and fecal accident by recording date
and time of the event, note whether formed stool or diarrhea,
and note the chlorine levels at the time or observation of the
event.
Check www.cdc.gov for latest information
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The correct use of
hyperchlorination for Crypto
ppm of free chlorine
25
20
15
correct
incorrect
10
5
0
0
1
2
3
4
5
6
7
8
9 10 11 12 13
time in hours
Keep the HOCl at 20 ppm for ENTIRE 13 hour period
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Gastrointestinal illness:
Community response to Crypto
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Crypto outbreaks are community wide
Ill bathers spread the outbreak as they migrate
from one pool to another
Swim teams and reciprocal memberships in
private pools are factors
Temporary closures cause ill bathers to move to
other pools – and spread the outbreak
Once the outbreak is identified all pools in the
regions must be hyperchlorinated at the same
time
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Gastrointestinal illness:
recommendations from the CDC
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Do not swim while experiencing diarrheal illness (e.g.,
swimming in or entering the water at pools, spas,
interactive fountains, lakes, rivers, or oceans) and for
2 weeks after diarrhea or symptoms resolve if one has
received a diagnosis of cryptosporidiosis or during an
outbreak of cryptosporidiosis.
Take children on frequent bathroom breaks and check
their diapers often.
Change diapers in the bathroom, not at the poolside.
Wash children thoroughly (especially their bottoms)
with soap and water after they use the toilet or their
diapers are changed and before they enter the water.
Shower before entering the water.
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Dermal disease
 Overview
of dermal disease.
 Why dermal disease?
 General symptoms.
 Two of dermal disease categories:
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Bacterial infections
Chemical induced rashes
 How
can you tell them apart?
 How do you control them?
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Dermal disease - overview
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We do not know the frequency of disease
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Rashes are not a “reportable” disease
Few bathers link skin infections to pools or spas
Evidence suggests rashes are extremely common
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Earaches are one of the leading causes of visits to pediatricians
during swimming season
Chemical reactions may affect >5% of bathers and produce short
term rashes
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Rashes likely out-number GI disease by 100s or 1000s
of times
 Most incidents cause discomfort but not serious illness

Many swimmers continue to swim with some minor rashes
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Why do we see dermal disease
with pool and spa use?
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Humans are not fish – we are not designed for repeated
long immersion in water
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Warm water dilates the pores
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“Stuff” in the water can enter the pores
This includes disinfection by-products and bacteria
Repeated exposure to anything out of the ordinary may
lead to immune system reactions
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Swimming dries out the skin
One type of very dry skin is called “eczema”
The medical term is “contact dermatitis”
Individual immune systems vary considerably
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Some groups are inherently more sensitive
Previous exposure makes some people hyper-reactive
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Dermal disease:
most common complaints
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General skin irritation or rash that may include any of the following:
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Irritation can be on:
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Arms, legs, extremities
Area covered by bathing suit
Generalized covering all body areas (less common)
Reactions may first be noticed:
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Reddened patches (erythema)
Particularly dry areas (xerosis)
Itchiness (puritis)
Weeping (pustular)
Hives (raised edematous [swollen] patches)
Quickly after touching water (or at least in <24 hours)
Days after touching the water (>24 hours up to 14 days)
Reaction may be:


Specific to just chlorine or bromine (most common)
Generalized to all halogen treated waters (in advanced cases)
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Dermal disease: Bacterial infection by
Pseudomonas aeruginosa
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Infection: bacteria inside hair
follicles resulting in immune
reaction (folliculitis)
Incubation: 2-14 days after
exposure, rarely <24 hours
Symptoms: Rash in armpits,
groin, abdomen and area
cover by bathing suit. Rash
may range from 2 mm red dots
(like a flea bite) to oozing
sores (like poison ivy).
Average duration: 8 days
Treatment: usually none
required, severe cases are
rare but may require IV
antibiotics
Typical Pseudomonas folliculitis cases
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Dermal disease: Sequence of a typical
Pseudomonas aeruginosa outbreak
1.
2.
3.
4.
5.
6.
7.
8.
P aeruginosa becomes established in biofilm
Sanitizer drops below critical level (bromine or
chlorine <1 ppm) and allows P aeruginosa to survive
in the water
Person stays in water >15 minutes
Warm water dilates pores in the skin
Bacteria enter the pores in the skin
Bacteria reproduce in the pores
Bacteria secrete toxins that cause allergic reactions
Immune system overcomes infection and toxins in
about 8 days
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Dermal disease: Why should
Pseudomonas aeruginosa worry you?
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This bacterium causes more outbreaks and single
cases of RWI than all others combined.
Nearly all cases are minor infections.
Because the rashes are minor they are seldom
reported, investigated or documented by local health
departments
Where this bacteria grows there are likely to be
other more serious ones also, such as E coli
O157:H7, Shigella and Legionella.
This bacteria is very easy to kill.
Rash outbreaks are an indicator of poor overall
sanitation in the facility.
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Dermal disease: reactions to
chemicals in the water
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Irritation: contact with
contaminated water
Incubation: <24 hours,
sometimes in 15 minutes
Symptoms: Itchy rash
on hands, arms, legs,
and area not covered by
bathing suit; may get
much worse if swimming
with a previous rash
Average duration: days
Treatment: none
required, change type of
sanitizer or stop
swimming in severe
cases
Severe contact dermatitis – few
pool/spa rashes are this bad
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Dermal disease:
possible chemical mechanisms
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Water dehydrates skin and removes protective oils
Disinfection by-products (chloramines and
bromamines) enter the skin
Repeated exposure (many, many events) leads to
low level irritation
Continued exposure leads to progressively stronger
immune reactions
With increasing age the skin becomes less oily and
this helps aggravate the reaction
With continued exposure some become crossreactive to all halogens and unable to enter water
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Quick rash comparison
Chemical reaction
Bacterial infection
Time to first
symptoms
<24 hours, can be
<10 minutes
>24 hours, often >2
days up to 14 days
Duration of
symptoms
Days to weeks
<14 days, usually 8
days
Typical
appearance
Red itchy rash
Red rash (like bug
bites)
Reaction on
re-exposure
Progressively worse
No change
Medical
treatment
Not usually required
Not usually required
Time between swimming and rash is the key to determining the cause
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Preventing dermal disease

Maintain chlorine or bromine at all times

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In pools keep combined chlorine to <0.2 ppm
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


Pseudomonas and Legionella thrive in under-treated
facilities – and that is not a good thing
Routinely use a non-halogen oxidizing treatment
(monopersulfate, ozone, or UV) instead of
superchlorination.
Stop breakpoint treatments that are used to reduce
persistent combined chlorine.
Replace water if oxidation does not work
Treat spas after every use period to oxidize
organics and convert bromide to bromine

Oxidize with potassium monopersulfate or chlorine
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Respiratory disease
 Overview
of respiratory disease
 Why respiratory disease?
 Two categories:


Bacterial infections
Chemical induced reactions
 Where
are they likely to happen?
 How do you control them?
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Respiratory disease:
Legionella pneumophila
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Grows in biofilms
O
O
 Thrives at 90 F to 106 F and
neutral pH
 Almost all infections from hot
tubs.
 WHO: 50+ outbreaks on
cruise ships
Not resistant to chlorine
Infection: inhaled contaminated
droplets, dose size unknown
Treatment: antibiotics
(Legionnaire’s Disease)
Vacation and rental properties
are high risk
There are documented
cases where individuals
became infected simply by
walking past a
contaminated hot tub with
the blowers on.
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Respiratory disease: sequence of a
typical Legionella spa outbreak
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Legionella pneumophila becomes established in biofilm
Bacteria break free of the biofilm
Chlorine level <1 ppm allows Legionella pneumophila to
survive in the water
Bubbles trap Legionella pneumophila
Air bubbles break the surface and burst
Fine droplets float in the breathing zone
Droplets are inhaled into the lungs
Bacteria enter White Blood Cells in the lungs
Bacteria reproduce inside the White Blood Cells
Outcome either Legionnaire’s Disease or Pontiac Fever
Legionellosis is not spread by person-to-person contact
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Respiratory disease:
Two forms of Legionellosis

Legionnaire’s Disease: severe form




Pneumonia plus fever, chills, cough
5-15% of cases result in fatality
Highest death rate in nosocomial cases and among
smokers (major risk factor)
Pontiac fever: less severe symptoms




Acute onset (36 hr.), flu-like, non-pneumonic
Self-limiting disease, seldom diagnosed
Recovery in 2-5 days without treatment
Most cases (perhaps >90%) of Legionella
infections are Pontiac Fever
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Respiratory disease: short and long
term chemical effects

Short term effects are well recognized


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Pool/spa smells due to combined chlorine or bromine
Patrons complaints indicate need for immediate
action
Health threat not high – unless sensitive patrons are
present, and you cannot predict this
Long term affects are emerging



Studies from Belgium have linked high indoor pool
usage to asthma indicators in school children
Studies are on-going
Implications for casual pool users or spa users are
not known
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Respiratory disease:
Where chemicals cause disease

Indoor pools due to




Out-gassing of compounds in the water
Poor general ventilation
Over-application of chlorine for break-point treatment
Spas of all types, especially if




Sanitizer is not maintained (Legionellosis)
pH drops to <5.5 and chlorine or bromine gas is
formed
Indoors and poorly ventilated
Over-application of chlorine for break-point treatment
(probably fairly rare)
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Respiratory disease:
Must do’s and four options

Maintain chlorine or bromine at all times to control
bacteria (especially true for Legionella)
 Maintain proper water management




Balance water to avoid forming chlorine or bromine gas
Use appropriate oxidation to control disinfection by-products
Don’t use breakpoint treatments on persistent chloramines
Consider these options




Replace superchlorination with monopersulfate, ozone, or UV
Use water replacement to dilute organics
Use adequate and optimized ventilation – don’t shut down the
system at night or you defeat the entire gas exchange process
Require all patrons to shower and reduce organic load
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RWI Summary

Gastrointestinal illness comes from bathers



Dermal disease is from operator errors



Maintaining 1 ppm FAC stops 1/3 of illnesses
Keep bathers who had diarrhea out of the pool for >7 days
1 ppm FAC or 2 ppm Bromine kills Pseudomonas
High chloramines or bromamines leads to rashes
Respiratory disease is from operator error or poor
facility design



1 ppm FAC or 2 ppm Bromine kills Legionella
Use oxidizing treatments appropriately to manage
chloramines or bromamines
Include adequate and optimized ventilation to remove
DBPs – especially at night
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“Model Aquatic Health Code”
from the CDC
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New model code for all types of aquatic facilities
13 modules covering all aspects of the facility
Witten by a consortium of experts from public
health, academia and industry
Main body is written in code language for easy
adoption by regulatory agencies
Detailed discussion in annex with references
Rolling release in 2011
www.cdc.gov/healthyswimming/
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Minimum disinfectant
concentrations in the MAHC
Disinfectant
Pools and other
aquatic venues
Spas
1.0 ppm without
cyanuric acid
Free chlorine
Total
Bromine
2.0 ppm with
cyanuric acid
3.0 ppm
3.0 ppm
6.0 ppm
(C) 2011 Vore & Associates
High risk
facilities
Must also use
an approved
Supplemental
Disinfection
System
Must also use
an approved
Supplemental
Disinfection
System
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Other parameters in MAHC
Parameter
Combined chlorine
pH
Total Alkalinity
Calcium Hardness
Cyanuric acid
TDS
Temperature
Water Balance
Value
< 0.4 ppm
7.2 to 7.8
80 to 150
<400
<50 ppm but none in high risk
facilities, spas, and indoors
<1500 ppm above initial TDS
-0.5 to +0.5
Spas 104OF, all others <90OF
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New manual on RWIs from the
National Swimming Pool Foundation
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Comprehensive review of RWIs
Discussion more detailed than MAHC annex
Separate chapters on GI, dermal, and
respiratory
In depth discussion of minimum disinfectant
levels and remedial treatments
Will be basis of new operator module from NSPF
Due out in summer 2011
www.NSPF.org
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General References & Resources
top three web sites likely to be the most useful
 CDC
Healthy Swimming @
www.cdc.gov/healthyswimming/
 National Swimming Pool Foundation @
www.NSPF.org
 The Association of Pool and Spa
Professionals @ http://apsp.org
 Guidelines
for safe recreational water
environments @ www.who.org
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Acknowledgment
 This
seminar was sponsored by Lowry &
Associates, Newmarket, ON
 For
additional information on testing
please contact Michael Lowry:


[email protected]
905-836-0505
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