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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.
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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 • 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.
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.
NSSP History • 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.
NSSP History • 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 • 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 • 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 • 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) • Cooperative program • Cooperative Partners: Federal, States, Industry • Regulatory program for the states • Public health protection program • Primary Mission: Illness prevention • 4 Main Elements • 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)
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 post harvest controls) • Standardize inspectors in plant inspections
Shellfish Dealer Certification Requirements • 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 • 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 • 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 ‘bio-acummulators’ for surrounding water
Bivalves are Filter Feeders • Molluscan shellfish feed on the phytoplankton and other substances they filter from the water. • 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 • Non-estuarine bacteria are usually eliminated by shellfish in 12-48 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.
Primary Growing Area Hazards • Bacterial pathogens • From fecal contamination: Humans and Animals • Naturally occurring (esp. Vibrio species) • Viral pathogens [human fecal contamination] • Naturally occurring toxins (produced by algae) that are NOT destroyed or eliminated by cooking • 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) • 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) • Vibrio infections, Vibrio vulnificus, Vibrio parahaemolyticus, And Vibrio cholerae Serogroup O1
Naturally Occurring Bacterial Hazard • 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)
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 • 1 Approved (Netarts Bay) • 5 Conditionally Approved • Interstate Approved Areas for commercial oyster production in Tillamook, Yaquina, Umpqua River Triangle, Coos Bay, South Slough) • Non-interstate Approved - Clatsop Beach razor clams, • Restricted - none • Conditionally Restricted - none • Prohibited (all areas not classified)
Shellfish Growing Area Status • 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: • 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: • Total Coliforms (since 1925) • Fecal Coliforms (since 1974) • 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? • 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 • 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: • Pathogenic organisms; • Poisonous or deleterious substances; • Marine biotoxins; • Bacterial concentrations exceeding standards for classification.
Naturally Occurring Hazards • 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 post-harvest processing.
The Monitoring and Control of the Growing Area and Harvest is KEY to Shellfish Safety • 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?