Download Basic Concepts of the National Shellfish Sanitation

Basic Concepts of the National Shellfish
Sanitation Program (NSSP)
OEHA Conference April 28-30, 2008 @ Bachelor Village, Bend Oregon
Basic Concepts by: Michael Antee, FDA
Additions and Edits by: Dawn Smith ODA
Main topics for our discussion today
• The National Shellfish Sanitation Program
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The State Shellfish Control Authority
Shellfish Biology and Primary Hazards of Concern
Water Quality
Classifications of Shellfish Growing Areas
Naturally Occurring Hazards: Biotoxins and
Vibrio bacteria
• Growing area classification and controlling
harvest
NSSP Background
Shellfish do not discriminate between
harmless organisms and pathogenic
bacteria.
 Shellfish are associated with typhoid
fever outbreaks in late 19th and early
20th centuries in Europe and the United
States.
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NSSP Background
A widespread typhoid epidemic
occurred in December of 1924. One
thousand five hundred (1,500) became
ill in Washington D.C., New York and
Chicago and several other small cities.
One hundred fifty (150) people died.
 The epidemic was traced back to
sewage polluted oysters.
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NSSP History
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At the request of the shellfish industry,
State Health Officials and the Surgeon
General held a conference of interested
health officials and industry
representatives to determine what
steps should be taken to ensure that an
epidemic would not happen again.
NSSP History
The participants formed the basis for
the system of shellfish sanitation
currently used in the United States and
many foreign countries.
 The system was based entirely upon a
cooperative understanding among the
States, the US Public Health Service,
and the shellfish industry.
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NSSP History
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As a result of that meeting, each party
recognized it had certain responsibilities
that it must carry out to ensure the safety
of shellfish. These responsibilities were
described in a report assembled by
Federal, State, and industry
representatives at the 1925 meeting.
“Report of Committee on Sanitary Control
of the Shellfish Industry in the United
States”
NSSP History
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That report, which was revised and
reissued in 1937 and 1947, marked the
beginning of the NSSP.
The document was latter separated into
two parts: PART II: “Sanitation of
Harvesting and Processing of Shellfish”
issued in 1957 and PART I: ”Sanitation of
Shellfish Growing Areas” issued in 1959.
NSSP History
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National Shellfish Sanitation Workshops
were held in 1954, 1956, 1958, 1961,
1964, 1968,1971, 1974, 1975, and 1977
continuing to reaffirm the need for this
specialized program and further
developing sanitary controls for
molluscan shellfish.
NSSP History
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The shellfish sanitation manuals have
been revised over the years (most
recently in 2007) based on new science
and food safety controls. Today the
sanitary controls for molluscan shellfish
are contained in a single document
titled “NSSP, Guide for the Control of
Molluscan Shellfish”.
The National Shellfish Sanitation
Program (NSSP)
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Cooperative program
Cooperative Partners: Federal, States, Industry
Regulatory program for the states
Public health protection program
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Primary Mission: Illness prevention
4 Main Elements
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Growing Area Classification
Control of Harvest (and Patrol)
Plant Sanitation (and Dealer Certification)
Laboratories (and NSSP-Approved Methods)
The National Shellfish Sanitation
Program (NSSP)
The NSSP Includes the following Molluscan Bivalve
Shellfish Species
- Clams
- Oysters
- Mussels
- Whole Scallops (not included in the program if only
the adductor muscle is marketed)
The NSSP Does Not Cover Crustaceans or Gastropods
- Shrimp (crustaceans)
- Lobsters (crustaceans)
- Crabs (crustaceans)
- Snails (gastropods)
Clams
Clams (Geoduck)
Oysters
Mussels
Scallops
The State of Oregon Participates in the NSSP by being a member of
the Interstate Shellfish Sanitation Conference (ISSC).
The Oregon Department of Agriculture acts as the State Shellfish
Control Authority (SSCA).
Functions of the State Shellfish
Control Authority (SSCA)
Classify
growing areas for approved harvest
Ensures that harvesting occurs only in approved
growing areas (conditional & approved areas)
Control harvesting from restricted areas
Prohibit harvesting in areas contaminated by
sewage or industrial wastes or bio-toxins
Contract with OSP to detect illegal harvest
through monitoring and patrol activities
Post warning signs when necessary for bio-toxin
closures
More Functions of SSCA
Issue certificate numbers and licenses to
dealers, wild harvesters and oyster
growers
 Conduct laboratory investigations
 Monitor control measures to ensure the
shellfish is harvested and processed under
sanitary conditions (Pre-harvest growing area and
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post harvest controls)
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Standardize inspectors in plant inspections
Shellfish Dealer Certification
Requirements
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Meet the requirements of the NSSP
Get certified by the State Shellfish Control
Authority
(SSCA)
Be listed as a Dealer in the Interstate Certified
Shellfish Shippers List online at ISSC.org
(ICSSL)
Be issued a numbered certificate by the SSCA
for each particular shellfish dealer activity
 OR 234 HV, OR 234 GR, OR 234 SS, OR 234 SP)
Harvesting and Growing Area Habitats
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Aquatic environments
Primarily in estuaries
On the bottom, buried in sediments, or
attached to rocks and reefs
Mobility of clams and scallops is limited
Oysters, mussels are essentially immobile
Limited movement – Means the quality of
surrounding water is an important safety
factor
Water Filtration by Shellfish
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Molluscan Bivalves must filter the surrounding
water in order to:
- Eat and metabolize food
- Breathe (respire)
- Reproduce
Shellfish filter large quantities of water
Shellfish act as ‘bio-filters’ and ‘bioacummulators’ for surrounding water
Bivalves are Filter Feeders
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Molluscan shellfish feed on the phytoplankton and
other substances they filter from the water.
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They strain food particles as they pump the water through
their bodies.
They accumulate and concentrate microorganisms
(including pathogens from the water) and contaminants to
levels higher than in the surrounding water.
General safety considerations
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Non-estuarine bacteria are usually eliminated by shellfish in 1248 hours.
Non-estuarine viruses take 2-4 weeks to be entirely eliminated
or inactivated.
Elimination or inactivation of toxins from harmful algal blooms
is highly variable, depending on the toxin and the species of
shellfish.
Most other chemicals will be incorporated in shellfish body
tissues and not eliminated.
Summary of Shellfish Biology Lessons
• Bivalve molluscan shellfish are essentially immobile
and generally captive to their environments.
• Bivalve molluscan shellfish are filter feeding animals,
and concentrate materials from the water, including
microorganisms and chemicals, as they strain out their
food.
• Some elimination of hazards can be achieved, but not
all hazards can be remedied.
Why must the NSSP Priority be on
Safety?
The MAIN reason
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Bivalves are commonly eaten raw,
alive and whole!
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Primary Growing Area Hazards
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Bacterial pathogens
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Viral pathogens [human fecal contamination]
Naturally occurring toxins (produced by algae) that
are NOT destroyed or eliminated by cooking
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From fecal contamination: Humans and Animals
Naturally occurring (esp. Vibrio species)
Paralytic shellfish poison (PSP; saxitoxins)
Amnesic shellfish poison (ASP; domoic acid)
Neurotoxic shellfish poison (NSP; brevetoxins)
Diarrhetic shellfish poison (DSP; okadiac acid)
Chemical contaminants and heavy metals
Biological Hazards Associated
with the Growing Area
Human fecal contamination (bacteria and
viruses)
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Typhoid fever (Salmonella typhi)
Hepatitis A Virus (HAV)
Norwalk viruses
Shigellosis (Group D and B Shigella bacteria)
Other Salmonellosis (from human and animal fecal contamination)
Naturally occurring bacteria (Vibrio species)
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Vibrio infections, Vibrio vulnificus, Vibrio parahaemolyticus,
And Vibrio cholerae Serogroup O1
Naturally Occurring Bacterial Hazard
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Some of the Vibrio species that naturally inhabit
the estuarine environment are pathogenic to
humans
Require salt and water > 60 ° F to grow and
flourish
V. vulnificus (mostly a gulf states problem)
V. parahaemolyticus (problem in Pacific NW,
1997 and 2006 outbreaks)
non-O1 V. cholerae (can be sporadic illnesses in
Pacific NW)
Naturally Occurring Biotoxins
•Biotoxins usually affect mussels and clams
•“Red tide” or algae blooms are caused by
planktonic algae or dinoflagellates (protozoans)
• The toxins are derivatives of saxitoxins
Paralytic Shellfish Poisoning (PSP)
Amnesic Shellfish Poisoning DA (ASP)
Neurotoxic Shellfish Poisoning (NSP)
Diarrheic Shellfish Poisoning (DSP)
Red Tides
Principal Sources of Fecal Contamination
• Discharges, effluents, bypasses, pipes (CSOs
and WWTPs)
• Rivers, streams, creeks, and seeps
• Vessel discharges (small and large)
• Runoff from precipitation
• Onsite Septic System failures
• Animal wastes (wildlife, pets, livestock)
Oregon has 6 Classified Shellfish Growing Areas
Approved for Interstate Commerce
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1 Approved (Netarts Bay)
5 Conditionally Approved
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Interstate Approved Areas for commercial oyster production in
Tillamook, Yaquina, Umpqua River Triangle, Coos Bay, South
Slough)
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Non-interstate Approved - Clatsop Beach razor clams,
Restricted - none
Conditionally Restricted - none
Prohibited (all areas not classified)
Shellfish Growing Area Status
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Open to harvest - means the shellfish are
predictably safe for consumption.
Closed to harvest - means the shellfish
are predictably unsafe or safety is
uncertain.
Closed Status Used When:
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Emergency condition or situation;
Presence of biotoxins or harmful algal
bloom;
Conditions identified in conditionally
approved or conditionally restricted area
management plan;
Failure to complete written sanitary survey
or triennial review evaluation report.
The Primary Indicators of Sanitation for
Growing Area Classifications are:
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Total Coliforms (since 1925)
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Fecal Coliforms (since 1974)
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Escherichia coli is under consideration by
the Interstate Shellfish Sanitation
Conference (considered approximately
equivalent to fecal coliforms)
Approved Area Classification Criteria
Classifications are based on results from the most
recent 15 water samples from every sample
site in the growing area.
Oregon uses the Fecal Coliform Standard:
Median MPN value of 14 fc/100 ml or less; and,
90% of those values at 43 MPN/100 ml or less
(for 5-tube procedure) or 49 MPN (for 3-tube
procedure).
How Strict is This Standard?
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To meet the approved water quality
criteria, it takes 8 million cubic feet of
coliform-free dilution water to dilute one
person’s waste in one day.
That is close to 6 million or slightly more
than 59,850,779 gallons of water.
That volume would cover 12 football fields
with 10 feet of water.
Additional Approved Area Criteria
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No direct discharges of wastewater effluents.
Not subject to contamination from human or
animal fecal matter at levels of public health
risk.
Not contaminated with:
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Pathogenic organisms;
Poisonous or deleterious substances;
Marine biotoxins;
Bacterial concentrations exceeding standards for
classification.
Naturally Occurring Hazards
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Not indexed by sanitation
Occurrences are uncontrolled by man
Avoidance strategies include plankton
monitoring for early warnings (cooperative
program with NOAA and ODFW)
Biotoxins – are controlled by monitoring
and closures
Vibrio species – hazards are controlled by
monitoring water temps, bacterial levels in
meats, occurrence of illness, or postharvest processing.
The Monitoring and Control of the Growing
Area and Harvest is KEY to Shellfish Safety
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Good water quality is essential to the production
of safe shellfish.
Once out of the water, shellfish retain what they
have accumulated.
Shellfish must come from “approved” areas with
predictably safe water quality.
Preventing the harvest of shellfish from
unapproved waters and closed areas is critical for
proper public health protection.
Thank you for the opportunity to provide
you with insight and knowledge about the
National Shellfish Sanitation Program.
Are the any questions?