
[Federal Register Volume 76, Number 203 (Thursday, October 20, 2011)]
[Notices]
[Pages 65200-65203]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-27101]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

[Docket No. FDA-2011-N-0731]


Risk Assessment on Norovirus in Bivalve Molluscan Shellfish: 
Request for Comments and for Scientific Data and Information

AGENCY: Food and Drug Administration, HHS.

ACTION: Notice; request for comments and for scientific data and 
information.

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SUMMARY: The Food and Drug Administration (FDA) is undertaking a 
collaboration with Health Canada, the Canadian Food Inspection Agency, 
Environment Canada, and Fisheries and Oceans Canada, to conduct a 
quantitative food safety risk assessment on norovirus in bivalve 
molluscan shellfish, specifically, oysters, clams, and mussels. FDA, on 
behalf of the collaborative team, is requesting submission of comments 
and scientific data and information that would assist in the 
development of the risk assessment.

DATES: Submit either electronic or written comments and scientific data 
and information by January 18, 2012.

ADDRESSES: Submit electronic comments and scientific data and 
information to http://www.regulations.gov. Submit written comments and 
scientific data and information to the Division of Dockets Management 
(HFA-305), Food and Drug Administration, 5630 Fishers Lane, Rm. 1061, 
Rockville, MD 20852.

FOR FURTHER INFORMATION CONTACT: Jane M. Van Doren, Center for Food 
Safety and Applied Nutrition (HFS--005), Food and Drug Administration, 
5100 Paint Branch Pkwy., College Park, MD 20740, 240-402-2927.

SUPPLEMENTARY INFORMATION: 

I. Background

    Noroviruses constitute a genus of genetically diverse, single-
stranded ribonucleic acid (RNA) viruses belonging to the family 
Caliciviridae (Ref. 1). Noroviruses cause millions of cases of acute 
gastroenteritis in the United States and thousands of cases in Canada 
annually (Refs. 2 to 4). The viruses can be transmitted through 
consumption of norovirus-contaminated food or water, through person-to-
person contact, or through contact with contaminated surfaces (Refs. 1 
and 5). Most norovirus outbreaks attributed to bivalve molluscan 
shellfish consumption have been traced to contamination during growth 
and harvest (Refs. 1 and 6). Bivalve molluscan shellfish are typically 
grown in estuaries, which may contain norovirus-contaminated human 
fecal material from municipal wastewater outfalls, combined sewer 
overflow, or non-point sources of pollution including human waste 
discharged from marine vessels (Refs. 6 to 8). Under some conditions, 
bivalve molluscan shellfish bioaccumulate waste contaminants (Ref. 9), 
thereby increasing the contaminant level in the bivalve molluscan 
shellfish relative to that in the water.
    Both the United States and Canada have developed detailed 
guidelines, in collaboration with their respective federal, state or 
provincial, tribal, and industry partners, to help ensure

[[Page 65201]]

shellfish food safety. The requirements described in these documents 
(Refs. 10 and 11) reflect a risk-based approach to reduce levels of 
indicator organisms, including total and fecal coliforms, thereby 
decreasing the probability of pathogenic contamination of shellfish.
    FDA, in collaboration with Health Canada, the Canadian Food 
Inspection Agency, Environment Canada, and Fisheries and Oceans Canada 
(the joint U.S.-Canada risk assessment team), is planning to conduct a 
quantitative risk assessment that can be used to evaluate the impact of 
preventive practices and controls on the risk of human norovirus 
illness associated with consumption of bivalve molluscan shellfish. The 
risk assessment will focus on norovirus contamination of bivalve 
molluscan shellfish arising from growth, harvest, and post-harvest 
processing. This risk assessment will focus on oysters, clams, and 
mussels. The principal objectives of this risk assessment are to:
     Evaluate the relative impact of selected factors (e.g., 
size of the community contributing to the municipal wastewater 
catchment, wastewater treatment, water temperature in bivalve molluscan 
shellfish growing and harvest areas, harvest season, post-harvest 
processes, food production practices, and consumption patterns) on the 
risk of human norovirus illness associated with the consumption of 
bivalve molluscan shellfish;
     Assess the impact on the level of risk of specified 
control measures currently used to mitigate risks from norovirus 
contamination of bivalve molluscan shellfish growing waters including 
those recommended by National Shellfish Sanitation Program (NSSP) and 
Canadian Shellfish Sanitation Program (CSSP);
     Identify additional preventive practices and controls that 
could be implemented in the future; and
     Inform the development of a Food Safety Objective (Ref. 
12) for norovirus contamination in bivalve molluscan shellfish and/or a 
Performance Objective (Ref. 12) for bivalve molluscan shellfish growth 
and harvest waters.

Contamination arising from transmission of norovirus from infected or 
ill food workers in food manufacturing or retail establishments to 
bivalve molluscan shellfish is outside the scope of this risk 
assessment.

II. Request for Comments, Scientific Data, and Information

    FDA, on behalf of the joint U.S.-Canada risk assessment team, is 
requesting comments, scientific data, and information to be considered 
in the design and development of the risk assessment. Data that include 
measurements of norovirus or enteric viral surrogate should identify 
the methods of analysis and detection, virus/surrogate and genotype 
detected, and recovery rate, if available (e.g., analysis of single 
oyster diverticulum using real-time reverse transcription quantitative 
polymerase chain reaction (RT-qPCR) for norovirus GII with 80% 
recovery). Areas of particular interest include epidemiology of 
norovirus illness, pre-harvest preventive practice and controls, post-
harvest preventive practices and controls, food preparation and 
consumption practices, and the relationship between norovirus dose and 
adverse health effects.

A. Epidemiology of Norovirus Illness

    We request data and information about the following aspects of the 
epidemiology of norovirus illness:
    1. Patterns of transmission of norovirus in different settings, 
such as in a community, a nursing facility, or a household;
    2. Proportion of norovirus illness due to person-to-person 
transmission, food consumption, and bivalve molluscan shellfish 
consumption;
    3. Proportion and determinants of individual resistance to 
norovirus infection;
    4. Underreporting rate for norovirus illnesses arising from 
consumption of norovirus-contaminated food in United States or Canada; 
and
    5. Models describing the transmission of norovirus in a population.

B. Preventive Practices and Controls and Other Factors Influencing 
Bivalve Molluscan Shellfish Contamination Levels

    We request data and information about the following aspects of 
preventive practices and controls and other factors influencing bivalve 
molluscan shellfish contamination levels:
    1. Prevalence of different types of treatment in municipal 
wastewater treatment (WWT) facilities in the United States and Canada, 
their relative size (population served), and their location relative to 
bivalve molluscan shellfish growing/harvest areas. Data submitted 
should also include information about treatment process(es) (e.g., 
sequence,timing, and/or concentration of bacteria/viral reducing agent) 
and effluent flow (volumerates of flow observed in the facility and the 
factors that influence the rate);
    2. Norovirus or enteric viral surrogate loads in raw wastewater and 
treated effluent from municipal WWT facilities as a function of type of 
treatment, water temperature, and season. Data should include the date 
and time of the measurement, volume rate of flow, weather, size of the 
community served, and the presence of norovirus outbreaks in the 
population at the time of measurement (if known). FDA specifically 
requests comparisons of norovirus or enteric viral surrogate loads in 
raw wastewater and WWT effluent obtained during the same time period 
and from the same facility;
    3. Experimental data and models describing dilution of WWT effluent 
in the estuary (e.g., water exchange rate and tidal flush volume) for a 
representative estuary or estuaries in general. Information should 
include details on calculations used within the model;
    4. Experimental data and models describing norovirus or enteric 
viral surrogate loss processes that may occur in an estuary, including 
inactivation by ultraviolet radiation or sunlight, association with 
particulate followed by sedimentation, and predation by marine 
organisms. Data submitted should include experimental conditions and 
ranges (e.g., water temperature, water salinity, season, and estuary 
water exchange rate);
    5. Concentration of norovirus or enteric viral surrogates in 
sediments, events that cause re-suspension of sediment, and data 
describing the relationship between nearby sediment and the 
concentration of norovirus or enteric viral surrogates in bivalve 
molluscan shellfish. Data submitted should include information about 
the sediment sampled (e.g., depth, temperature, water salinity, season) 
and shellfish sampled (e.g., nutrient availability, growth substrate, 
water temperature, water salinity, season, species, and animal 
variance), if applicable;
    6. Characteristics of sites where stratification of WWT effluent 
discharge in the water column occurs (e.g., temperature, salinity, 
depth, surface winds, storm activity, local hydrodynamics, and outfall 
design) and the impact of these characteristics on norovirus or enteric 
viral surrogate concentrations in bivalve molluscan shellfish growing/
harvest areas (e.g., plume movement and mixing);
    7. Norovirus or enteric viral surrogate loads from marine vessel 
discharge, combined sewer overflow, or other sporadic events that might 
contaminate bivalve molluscan shellfish growing/harvest areas;
    8. Uptake rate of norovirus or enteric viral surrogates by bivalve 
molluscan shellfish and determinations of the

[[Page 65202]]

bioaccumulation factor (BAF). Data and information should include a 
description of the impacts of pathogen particle association, 
concentration of the pathogen in the water surrounding the bivalve 
molluscan shellfish, nutrient availability, growth substrate, water 
temperature, water salinity, season, species, and animal variance on 
this rate and the BAF. Data submitted should specify the experimental 
conditions during which uptake was measured (e.g., batch feeding, flow-
through feeding, or natural environmental conditions);
    9. Inactivation rate of norovirus or enteric viral surrogates 
within bivalve molluscan shellfish, including the impacts of nutrient 
availability, growth substrate, water temperature, water salinity, 
season, species, and animal variance on this rate. Data submitted 
should specify the experimental conditions during which inactivation 
was measured (e.g., batch, flow-through, or natural environmental 
conditions);
    10. Elimination rate of norovirus or enteric viral surrogates from 
bivalve molluscan shellfish including the impacts of nutrient 
availability, growth substrate, water temperature, water salinity, 
season, species, and animal variance on this rate. Data submitted 
should specify the experimental conditions during which elimination was 
measured (e.g., batch, flow-through, or natural environmental 
conditions); and
    11. Models that specifically address uptake, inactivation and 
elimination of norovirus or enteric viral surrogates by bivalve 
molluscan shellfish.

C. Post-Harvest Preventive Practice and Controls and Other Factors 
Influencing Bivalve Molluscan Shellfish Contamination Levels

    We request data and information about the following aspects of 
post-harvest preventive practice and controls and other factors 
influencing bivalve molluscan shellfish contamination levels:
    1. Regional and seasonal landings of bivalve molluscan shellfish 
species in the United States and Canada;
    2. Prevalence and concentration of norovirus or enteric viral 
surrogates in bivalve molluscan shellfish at the time of harvest, 
classified by species, location, and seasonal landing;
    3. Proportion of bivalve molluscan shellfish, by species, that 
undergo wet storage, relaying and depuration and the conditions (e.g., 
times and temperatures) of these practices as applied by the shellfish 
industry. Data are also requested to determine whether shellfish 
undergoing these different treatments preferentially serve different 
postmarkets (e.g., raw/cooked);
    4. Experimental data and models that describe the impact of wet 
storage, relaying, and depuration on the concentration of norovirus or 
enteric viral surrogate in bivalve molluscan shellfish. Data submitted 
should specify process and experimental conditions including parameter 
ranges (e.g., process time, water temperature, water salinity, nutrient 
availability, growth substrate, species, and season) as well as animal 
variance;
    5. Proportion of bivalve molluscan shellfish, by species, that 
undergo high hydrostatic pressure (HHP), mild heat, irradiation, 
freezing, or other postharvest processes. Data are also requested to 
determine whether bivalve molluscan shellfish undergoing these 
different treatments preferentially serve different postmarkets (e.g., 
raw/cooked);
    6. Protocols/conditions and parameter ranges for HHP, mild heat, 
irradiation, freezing, or other postharvest processes as applied to 
bivalve molluscan shellfish by the shellfish industry; and
    7. Experimental data and models that describe the impact of HHP, 
mild heat, irradiation, freezing, or other post-harvest processes on 
the concentration of norovirus or enteric viral surrogate in bivalve 
molluscan shellfish. Data submitted should specify the processing and 
experimental conditions, parameter ranges (e.g., time, pressure and 
temperature), species, and animal variance.

D. Preventive Practice and Controls and Other Factors Influencing 
Bivalve Molluscan Shellfish Contamination Levels During Food 
Preparation and Bivalve Molluscan Shellfish Consumption Data

    We request data and information about the following aspects of 
preventive practice and controls and other factors influencing bivalve 
molluscan shellfish contamination levels during food preparation and 
bivalve molluscan shellfish consumption:
    1. Proportion of bivalve molluscan shellfish, by species, eaten raw 
and cooked, including method of cooking (e.g., steaming, frying, or 
baking);
    2. Distribution of bivalve molluscan shellfish meal sizes, 
categorized by species, with regard to season, region, and preparation 
technique;
    3. Distribution of temperatures and times associated with cooking 
methods (e.g., steaming, frying, or baking) for bivalve molluscan 
shellfish, by species;
    4. Experimental data and models describing the impact of food 
preparation technique on the concentration of norovirus or enteric 
viral surrogates in bivalve molluscan shellfish, by species. Data 
submitted should include food preparation and cooking parameters and 
ranges (e.g., temperature and time); and
    5. Prevalence distribution of norovirus or enteric viral surrogate 
in bivalve molluscan shellfish, by species, at the point of consumption 
as a function of season, region and preparation technique.

E. Relationship Between Norovirus Dose and Adverse Human Health Effects

    We request data and information about the following aspects of the 
relationship between norovirus dose and adverse human health effects 
including:
    1. Human or animal studies that describe the relationship between 
norovirus dose and the probability and severity of human illness;
    2. Human norovirus outbreak data that describe the relationship 
between norovirus dose and the probability and severity of human 
illness; and
    3. Epidemiological and mechanistic data identifying/describing 
different rates of illness or health outcomes for particular 
populations (e.g., vulnerable/susceptible populations and resistant 
populations) exposed to norovirus.

III. Comments

    Interested persons may submit to the Division of Dockets Management 
(see ADDRESSES) either electronic or written comments and scientific 
data and information regarding this document. It is only necessary to 
send one set of comments and scientific data and information. It is no 
longer necessary to send two copies of mailed comments and scientific 
data and information. Identify comments and scientific data and 
information with the docket number found in brackets in the heading of 
this document. Received comments and scientific data and information 
may be seen in the Division of Dockets Management between 9 a.m. and 4 
p.m., Monday through Friday.

IV. References

    The following references have been placed on display in the 
Division of Dockets Management (see ADDRESSES) and may be seen by 
interested persons between 9 a.m. and 4 p.m., Monday through Friday. 
(FDA has verified the Web site addresses, but we are not responsible 
for any subsequent changes to the Web sites after this document 
publishes in the Federal Register.)
    1. Centers for Disease Control and Prevention, Norovirus Technical 
Fact

[[Page 65203]]

Sheet, http://www.cdc.gov/ncidod/dvrd/revb/gastro/norovirus-factsheet.htm.
    2. Centers for Disease Control and Prevention, Norovirus: 
Surveillance, Disease Burden, and Disease Reduction Activities, http://www.cdc.gov/ncidod/dvrd/revb/gastro/norovirus-surv-disease-burden.htm.
    3. National Microbiology Laboratory and Public Health Agency of 
Canada, National Enteric Surveillance Program, ``Annual Summary of 
Laboratory Surveillance Data for Enteric Pathogens in Canada,'' 2009.
    4. Majowicz, S.E., V.L. Edge, A. Fazil, et al., ``Estimating the 
Under-Reporting Rate for Infectious Gastrointestinal Illness in 
Ontario,'' Canadian Journal of Public Health, vol. 96, pp. 178-181, 
2005.
    5. Gerba, C.P. and D. Kayed, ``Caliciviruses: A Major Cause of 
Foodborne Illness,'' Journal of Food Science, vol. 68, pp. 1136-1142, 
2003.
    6. Kohn, M.A., T.A. Farley, T. Ando, et al., ``An Outbreak of 
Norwalk Virus Gastroenteritis Associated With Eating Oysters: 
Implications for Maintaining Safe Oyster Beds,'' Journal of the 
American Medical Association, vol. 273, pp. 466-471, 1995.
    7. Shieh, Y.C., R.S. Baric, J.W. Woods, et al., ``Molecular 
Surveillance of Enterovirus and Norwalk-Like Virus in Oysters Relocated 
to a Municipal-Sewage-Impacted Gulf Estuary,'' Applied and 
Environmental Microbiology, vol. 69, pp. 7130-7136, 2003.
    8. J.A. Lowther, K. Henshilwood, and D.N. Lees, ``Determination of 
Norovirus Contamination in Oysters From Two Commercial Harvesting Areas 
Over an Extended Period, Using Semiquantitative Real-Time Reverse 
Transcription PCR,'' Journal of Food Protection, vol. 71, pp. 1427-
1433, 2008.
    9. Burkhardt, W., III and K. Calci, ``Selective Accumulation May 
Account for Shellfish-Associated Viral Illness,'' Applied Environmental 
Microbiology, vol. 66, pp. 1375-1378, 2000.
    10. National Shellfish Sanitation Program (NSSP) Guide for the 
Control of Molluscan Shellfish 2009 Revision, http://www.fda.gov/Food/FoodSafety/Product-SpecificInformation/Seafood/FederalStatePrograms/NationalShellfishSanitationProgram/ucm046353.htm.
    11. Canadian Shellfish Sanitation Program (CSSP) Manual of 
Operations, http://www.inspection.gc.ca/english/fssa/fispoi/man/cssppccsm/shemolalle.pdf.
    12. Joint Food and Agriculture Organization of the United Nations/
World Health Organization Food Standards Program, Codex Alimentarius 
Commission Procedural Manual, 20th ed. 113, 2011, ftp://ftp.fao.org/codex/Publications/ProcManuals/Manual_20e.pdf.

    Dated: October 14, 2011.
Leslie Kux,
Acting Assistant Commissioner for Policy.
[FR Doc. 2011-27101 Filed 10-19-11; 8:45 am]
BILLING CODE 4160-01-P


