Download Louisiana Response to Naegleria fowleri in Drinking Water

Louisiana Response to
Naegleria fowleri in Drinking Water
Jonathan “Jake” Causey, P.E.; Louisiana DHH
2014 SWAWWA
Overview
• Louisiana background
– St. Bernard Parish
– DeSoto Parish
• Risk mitigation and communication
• Science Advisory Workgroup
• Emergency Rule
– Increased monitoring requirements
– Monitoring Plan Portal
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St. Bernard and DeSoto follow-up sampling
Laboratory testing capacity
Statewide surveillance program
Questions
Louisiana Background
• In 2011, two people died of Primary Amebic
Meningoencephalitis (PAM) caused by Naegleria fowleri
(brain-eating amoeba) in DeSoto Parish and St. Bernard
Parish. Both cases involved the use of a neti-pot.
• In 2013, there was second death in St. Bernard Parish (4year old boy) caused by PAM and confirmed to be Naegleria
fowleri (Nf) infection.
• Testing conducted in 2013 by Louisiana DHH/CDC in both
St. Bernard and DeSoto found this amoeba in the treated
distribution system water supply.
• Both systems use conventional treatment and chloramine
disinfection to treat surface water. Common issue: low to no
chlorine residuals in areas where Nf was detected.
3
Louisiana Background
DeSoto
St. Bernard
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St. Bernard Parish: Initial CDC Samples
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DeSoto Parish: Initial CDC Samples
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Risk Mitigation and Communication
• LDHH, CDC, and EPA formed response team
• LDHH directed St. Bernard water utility to raise residual
chlorine levels to ≥ 1.0 mg/L throughout the system (“chlorine
burn”)
• LDHH conducted weekly testing of chlorine residuals
• LDHH and CDC communications teams developed briefing
documents and fact sheets
– Challenge: How to communicate to the public that water was
“Safe to Drink” but “Not Safe to Get Up Your Nose”
– Schools shut down swimming pools and turned off drinking
water fountains
St. Bernard Chlorine Burn: Week 1
2011 PAM
Case
WTP
2013 PAM
Case
St. Bernard Chlorine Burn: Week 2
2011 PAM
Case
WTP
2013 PAM
Case
St. Bernard Chlorine Burn: Week 3
2011 PAM
Case
WTP
2013 PAM
Case
St. Bernard Chlorine Burn: Week 4
2011 PAM
Case
Another 6 weeks were needed to
achieve 1 mg/L FC at all DS locations
WTP
2013 PAM
Case
Science Advisory Workgroup
• In response to the detection of Naegleria fowleri in St.
Bernard Parish and DeSoto Parish systems in Louisiana, the
Department of Health and Hospitals formed a Science
Advisory Workgroup.
• The workgroup consists of:
Louisiana DHH
U.S. Centers for Disease Control
U.S. Environmental Protection Agency
Louisiana State University
Tulane University
University of Arizona
City of Peoria, AZ
City of Tucson, AZ
Southern Australia
Western Australia
Louisiana Poison Control
Arizona DEQ
Corona Environmental Consulting
Later – Karachi, Pakistan
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Science Advisory Workgroup
Key objectives of the NFSAWG include:
1. Informing LDHH about the current state of knowledge
regarding Naegleria fowleri
2. Informing ongoing and anticipated rulemaking
3. Identify opportunities and methods to better educate water
systems on current standards and regulations
Some of the questions to answer are as follows:
1. What is the occurrence of Naegleria fowleri in public water
system distribution systems?
2. What is the risk of infection of Naegleria fowleri when it is
present in a public water supply?
3. What treatment, operational, and/or monitoring practices are
necessary to control the presence of Naegleria fowleri in public
water systems at a level that will prevent or reduce the risk of
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infection to an acceptable level?
Emergency Rule
• LDHH issued an Emergency Rule (ER) on November 6,
2013 that remains in effect:
• The purpose is to ensure that all points in the distribution
system maintain a disinfectant residual level that will control
the Naegleria fowleri amoeba and to ensure adequate
monitoring by public water systems for total coliform and
disinfectant residual levels in the distribution system
• Effective November 6, 2013, 25% more monitoring required
for disinfectant residual concentration (chlorine or chloramine).
• Effective February 1, 2014, 50% more sites required for total
coliform and chlorine monitoring and the new minimum
disinfectant residual level is:
•
•
0.5 mg/l of free chlorine; or
0.5 mg/l of chloramine residual (measured as total chlorine) for
systems that feed ammonia.
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What else does the Emergency Rule require?
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All systems must submit and maintain a monitoring plan with all total
coliform and chlorine residual sample sites (POE, TCR, ACR, and MRT)
by January 1, 2014.
• The monitoring plan shall be entered and submitted via the
Monitoring Plan Portal (MPP) - https://www.ldhh-mpp.org/ with
valid 911 street addresses or latitude/longitude coordinates for each
sample site.
Systems (GW and SW) that chloraminate (chlorine with ammonia
addition) must develop and submit a Nitrification Control Plan by
March 1, 2014.
Chlorine residuals must be measured using EPA-approved analytical
methods. New analytical methods added to Table 1 of LAC
51:XII.1105.C. But this means that color wheels are no longer acceptable
for measuring the disinfectant residual concentration (free or total
chlorine).
Clarifies that records of chemical tests/measurements shall be kept and
maintained as prescribed by federal regulations (i.e., 10 years for chlorine
residuals).
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St Bernard and DeSoto Follow-up Results
• LDHH / CDC sampling and analysis conducted following 60 day free
chlorine burn and return to chloramination
Sampling Period
January 2014
May 2014
September 2014
St. Bernard
Negative
Negative
Result pending
DeSoto
Negative
Negative
Result pending
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LDHH Develops Laboratory Testing Capacity
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LDHH developed laboratory testing capacity following methods
in peer reviewed literature, CDC, Australian, and other laboratories
Two collection methods: 1) 1L grabs, and 2) 100L samples
concentrated on ultrafilters (UFs)
Samples are concentrated by centrifugation (for the UFs after
backwashing).
Supernatant removed and packed pellet mixed with a culture of
E.coli and plated on Nelson’s agar and incubated at 42 deg C for
up to 7 days
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LDHH Develops Laboratory Testing Capacity
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•
•
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Plates examined daily using an inverted microscope to observe the
development of amoebae
• If trophozoites are detected, this indicates the presence of
thermophilic amoebae
On an amoebae positive plate, a portion of the growth where they
are observed is tested for the production of flagella
• Flagella positive amoebae are the genus Naegleria
At 7 days incubation, the entire surface of the plate is harvested,
centrifuged to produce a pellet, and analyzed by qPCR to
determine if the Naegleria detected is the species fowleri
Ongoing precision and recovery, matrix spikes, methods blanks,
and negative controls are included with each sample batch
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LDHH Launches Surveillance Program
•
August 11, 2014: DHH launched a Naegleria fowleri surveillance
program to begin investigating water system sources and treated
water distribution system locations
• Statewide geographic coverage
• Small and large water systems
• Predominantly chloramine residual disinfectant, but some free
chlorine
• Predominantly surface water supply, but some groundwater
• Sampling intended to continue until water sample temperatures
drop below 20 degrees C
•
Also closely monitoring disinfectant residual concentrations
compared with 0.5 mg/L minimum requirement
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Additional Responses
•
Water system training
• Delivered eight 16-hour distribution system water quality
training courses across the state
• Focused on monitoring, reporting, maintaining disinfectant
residuals
• Lots of lessons learned…
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Information management system improvements
• Disinfectant residual data capture and reporting
•
Act 573 of the 2014 Louisiana Legislative Session
• Requires DHH to promulgate a rule requiring more than a
“trace” amount of chlorine residual.
•
Published White Paper that was included in the October JAWWA
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E418
Bartrand et al | http://dx.doi.org/10.5942/jawwa.2014.106.0140
Pe e r -Re v i e w e d
Naegleria fowleri: An emerging drinking water pathogen
TIMOTHY A. BARTRAND1 , JONATHAN JAKE CAUSEY, 2 AND JENNIFER L. CLANCY1
1
2
Corona Environmental Consulting, LLC
D HH-OPH Engineering Services, Louisiana Department of Health and Hospitals, Office of Public Health
Naegleria fowleri (N. fowleri) is a free-living, trophic amoeba
that is nearly ubiquitous in the environment and can be present
in high numbers in warm waters. It is the causative agent of
primary amoebic meningoencephalitis (PA M ) , a rare but
particularly lethal disease with a very low survival incidence.
Although N. fowleri was isolated from drinking water supplies
in Australia in the 1980s, it was not considered a drinking water
threat in the United States until recent cases were associated with
a groundwater system in Arizona and surface water systems in
Louisiana. N. fowleri in drinking water treatment and distribution
systems can be managed using disinfectant concentrations
typically encountered in well-run plants although nitrification
and attendant low disinfectant residuals may pose a challenge for
some systems. The greatest challenge for N. fowleri control is in
premise plumbing systems where conditions are largely outside
the control of utilities, residuals might be low or nonexistent, and
where water temperatures could be high enough to support rapid
growth of the amoebae. This article reviews published studies
describing the environmental occurrence, survival, pathogenicity,
and disinfection of N. fowleri. In addition, this article provides
information about this little known and poorly understood
parasite with respect to its occurrence in the environment; how
the amoeba amplifies in water systems such that it can cause
infection; how N. fowleri has been successfully controlled for
decades in water systems through treatment and distribution
system management in Australia; and the knowledge gaps and
information needed to address N. fowleri as an emerging
pathogen in US water supplies.
Keywords: Naegleria fowleri, premise plumbing, microbial risk
JOURNAL AWWA
Primary amoebic meningoencephalitis (PAM) occurs infrequently in the United States with 132 cases identified between
1962 and 2013 (CDC, 2014). When it does occur, cases are often
reported in the popular media. In these reports, N. fowleri is usually referred to as the “brain-eating amoeba,” and it is noted that
infections are nearly always fatal. The implication of treated
drinking water in cases of PA M in Louisiana (CDC, 2014) has
increased the profile of N. fowleri as a pathogen of concern in
the drinking water community in the United States. In response
to public concerns over PA M , Louisiana promulgated an emergency rule (La. Admin. Code 51:XII.311, 355, 357, 361, 363, 367,
903, 1102, 1105, 1113, 1117, 1125, 1133, 1135, 1139, and 1503)
requiring higher disinfection residuals and more frequent residual
measurements in public water supply distribution systems.
N. fowleri is a free-living amoeba (FLA) that occurs naturally
in soil and water. The life stages of N. fowleri are ameboid trophozoite, flagellate, and cyst. Only the ameboid trophozoite is
infectious (CDC, 2013). N. fowleri grows well at temperatures
between 25 and 42°C and survives for extended periods at lower
temperatures, particularly in its encysted form (CDC, 2013; see
the photographs on page E420). Although more than 30 species
of Naegleria have been identified through D N A sequencing, N.
fo wleri is the only species that has been implicated in human
disease to date (De Jonckheere, 2004; De Jonckheere, 2002). De
Jonckheere (2011) notes N. fowleri has been detected on all continents except Antarctica, and PA M cases have occurred in trop-
ical, subtropical, and even temperate regions. As of 2011, eight
types of N. fowleri had been identified, and those types occur
with differing frequency on the different continents. There does
not appear to be a significant difference in the virulence of the
types (De Jonckheere, 2011). Two additional Naegleria species,
N. australiensis and N. italica, have been shown to cause infections in lab animals (De Jonckheere, 2002).
PA M is a disease with a high fatality rate, ~ 98%, and death
normally occurs within 1–12 days postinfection ( CD C , 2011).
Most victims of PA M are children or young adults in good
health with a history of swimming in naturally warm or thermally polluted waters where growth of the amoebae is favored.
Cases potentially linked to inhalation of drinking water or
perhaps from contamination of premise plumbing have been
suggested in reports of PA M among people with no recent history of swimming (Hunte et al, 2013; Kazi & Riaz, 2013; State
of Louisiana Department of Health and Hospitals, 2013; Movahedi et al, 2012; Yoder et al, 2012; Khanna et al, 2011, Shakoor
et al, 2011). Some of these nonswimming cases appear related
to specific practices such as neti pot use or ritual nasal cleansing;
however, the most recent cases in Karachi, Pakistan, have no
connection to ritual nasal cleansing or any recreational water
exposure (Zafar, 2014). Although occurrence of N. fowleri is
widespread in the natural environment, there are relatively few
cases of PA M reported annually. This paradox forms the backdrop for this review.
OCTOBER 2014 | 106:10
2014 © American
Water Works
Association
Next Steps
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Laboratory Method Development
• Continued development of laboratory methodologies for the detection of
thermophilic amoeba, Naegleria, and Naegleria fowleri.
• Other amoeba’s need consideration or should be part of the analysis such
as Acanthamoeba?
•
Occurrence study in groundwater sources
• Louisiana has approximately 2500 public supply water wells
•
Need a better understanding of the likelihood of having Naegleria fowleri
present when thermophilic amoebas and/or thermophilic Naegleria are
present.
• These should likely be used as indicators similar to total coliforms
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Data to allow estimation of the contamination of distribution system water
with N. fowleri during maintenance, main breaks, and other disturbances in
distribution
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Questions
Jonathan “Jake” Causey, P.E.
Chief Engineer / Safe Drinking Water Administrator
DHH-OPH, Engineering Services
225-342-7499
[email protected]
LDHH Safe Drinking Water Program:
www.dhh.la.gov/SafeDrinkingWater
Louisiana Information and Press Releases on Naegleria fowleri:
www.dhh.la.gov/waterfacts