13 Proposed Draft Guidelines for the Application of General Principles. . .
159
Primary Production/Harvesting Area
Potential sources of viral contamination of the environment should be identified
prior to production activities and food production should not be carried out in
areas where the presence of viruses may lead to the viral contamination of food. In
addition, hygiene and health requirements (see section on “Establishment: Personal
Hygiene”) should be followed to ensure that personnel who come directly into
contact with food during production do not contaminate the product with fecal
material or vomit. Water for primary production should be suitable for its intended
use and not compromise food safety.
Bivalve Molluscs and Primary Production/Harvesting Area
It is important to ensure the seawater quality of growing areas for bivalve molluscs
by improving sewage treatment efficiency for virus removal/inactivation and to
avoid discharging inadequately treated sewage near the bivalve molluscs growing
areas, e.g. from ships, recreational boats and of harvesting vessels. Sewage treatment
plants should be designed to minimize storm overflows and leakage from private
septic tanks or sewage collecting networks should be prevented.
A sanitary survey of harvesting and/or growing water should include an assessment of possible human fecal contamination sources and the intensity of the survey
should be in agreement with the occurrence of viral diseases in the human domain
and weather conditions, e.g. after heavy rain fall. E. coli/fecal coliforms/total
coliforms are used as indicators for fecal contamination, however viruses may be
present in the absence of bacterial indicators, e.g., a short-term depuration process
commonly reduces low levels of bacterial contamination, but is inadequate for the
elimination of viruses.
When there is a likelihood or evidence of virus contamination from epidemiological information, environmental events (e.g., heavy rainfall or sewage
treatment overflows), or direct detection through virological analysis, closure of
the area, destruction of contaminated bivalve molluscs, virucidal heat treatment
before consumption or long term relaying for already harvested bivalve molluscs
is recommended. Another option is a combination of depuration and relaying as
determined by the competent authority. Viral testing of the bivalve molluscs or an
equivalent approach to ensure safety should be used as part of the process of reopening the affected harvesting area depending on the requirements of the competent
authority, using either standardized methods or alternative validated methods. Other
conditions, including meeting the sanitary survey requirements, should also have
been satisfied as a condition of reopening the area. In addition, suitable precautions
should be taken to protect bivalve molluscs from being contaminated by human fecal
material on board harvest vessels, and facilities and toilets on harvest vessels should
be such to ensure that an appropriate degree of personal hygiene can be maintained.
159
Primary Production/Harvesting Area
Potential sources of viral contamination of the environment should be identified
prior to production activities and food production should not be carried out in
areas where the presence of viruses may lead to the viral contamination of food. In
addition, hygiene and health requirements (see section on “Establishment: Personal
Hygiene”) should be followed to ensure that personnel who come directly into
contact with food during production do not contaminate the product with fecal
material or vomit. Water for primary production should be suitable for its intended
use and not compromise food safety.
Bivalve Molluscs and Primary Production/Harvesting Area
It is important to ensure the seawater quality of growing areas for bivalve molluscs
by improving sewage treatment efficiency for virus removal/inactivation and to
avoid discharging inadequately treated sewage near the bivalve molluscs growing
areas, e.g. from ships, recreational boats and of harvesting vessels. Sewage treatment
plants should be designed to minimize storm overflows and leakage from private
septic tanks or sewage collecting networks should be prevented.
A sanitary survey of harvesting and/or growing water should include an assessment of possible human fecal contamination sources and the intensity of the survey
should be in agreement with the occurrence of viral diseases in the human domain
and weather conditions, e.g. after heavy rain fall. E. coli/fecal coliforms/total
coliforms are used as indicators for fecal contamination, however viruses may be
present in the absence of bacterial indicators, e.g., a short-term depuration process
commonly reduces low levels of bacterial contamination, but is inadequate for the
elimination of viruses.
When there is a likelihood or evidence of virus contamination from epidemiological information, environmental events (e.g., heavy rainfall or sewage
treatment overflows), or direct detection through virological analysis, closure of
the area, destruction of contaminated bivalve molluscs, virucidal heat treatment
before consumption or long term relaying for already harvested bivalve molluscs
is recommended. Another option is a combination of depuration and relaying as
determined by the competent authority. Viral testing of the bivalve molluscs or an
equivalent approach to ensure safety should be used as part of the process of reopening the affected harvesting area depending on the requirements of the competent
authority, using either standardized methods or alternative validated methods. Other
conditions, including meeting the sanitary survey requirements, should also have
been satisfied as a condition of reopening the area. In addition, suitable precautions
should be taken to protect bivalve molluscs from being contaminated by human fecal
material on board harvest vessels, and facilities and toilets on harvest vessels should
be such to ensure that an appropriate degree of personal hygiene can be maintained.