Flashcards in Food borne risks by commondity and risk management Deck (66):
What are the origins of food-borne hazards?
(Add diagram from slide 5 here)
Which pathogen has the highest case fatality rate in the UK?
Which pathogen causes the most food-borne disease in the UK?
Which pathogen causes the highest absolute number of deaths in the UK?
What does the public health impact of a food borne disease depend on?
Total number of cases and severity of the cases (numbers hospitalised, deaths)
Which food group is associated with the highest risk of food borne disease per serving?
What are the two main biological hazards from chicken meat?
Campylobacter and Salmonella enteritidis
What is considered to be the main food borne source of human campylobacteriosis?
What is the distribution of Campylobacter in the UK?
Endemic in animals (poulty, sheep, cattle, pigs)
Sources include food and non-food borne, mainly found in poultry but also red meat, raw milk and untreated water
What are the clinical signs associated with campylobacteriosis? What is its infectious dose?
Low infectious dose
Incubation period of 2-5 days and is self-limiting in 10 days
Diarrhoea, abdominal pain, a rare sequelae is Gillan-Barre Syndrome
What is the seasonal change that campylobacteriosis shows? Why is this? Does the same change occur in poultry and chickens?
Seasonal peak in late spring and summer
Probably an effect of environmental and climatic conditions
Humans and poultry show same peak but sometimes the rise in human cases precedes the rise in chickens
What is the aim of the FSA's Campylobacter Risk Management Program?
To reduce levels of Campylobacter in chicken targeting different points along the food chain
Reduce the number of birds with the highest level of infection from the current 27% to 10% which will reduce the number of Campylobacter food poisonings by 30%
What on farm interventions are being carried out to try and reduce levels of Campylobacter?
Biosecurity, feed and water additives that reduce the risk of colonisation, vaccination and genetic resistance
What interventions are being carried out at slaughtering to try and reduce levels of Campylobacter?
Logistic slaughter where flocks with high burden are slaughtered after birds with low burden of bacteria
Freezing, treating with hot water and chemical decontamination
Which products commonly cause Salmonellosis?
Poultry, eggs and desserts
(4-5% poultry contaminated at retail but due to vaccination this number is now likely to be lower)
What are the clinical signs of salmonellosis?
Incubation period of 12-48 hours, self-limiting in 3-5 days
Diarrhoea, vomiting, abdominal pain, fever
What are the different Salmonella species associated with each animal?
Cattle = S. dublin
Sheep = S. diarizonae
Pigs = S. typhimurium
Poultry = S. enteritidis
When are eggs contaminated with Salmonella?
Can be before the shell is formed
What control programmes are in place at the level of breeder flocks to control Salmonella?
Compulsory testing for Salmonella
If positive for S. enteritidis or S. typhimurium then the flock is slaughtered
UK breeding sector is effectively free of S. enteritidis and S. typhimurium
What control programmes against Salmonella are in place at the level of layer flocks?
What Salmonella control programmes are used at the level of broilers in the poultry industry?
Testing before slaughter followed by cleaning, disinfection and monitoring when positive results are found
What control programmes for Salmonella were instigated in turkey breeding and fattening flocks in 2010?
3 year program
Sampling and testing followed by cleaning, disinfection and monitoring when positive results found
What does the British Lion Quality mark mean?
Egg have been produced to the highest quality standards of food safety
Compulsory vaccination vs Salmonella, independent auditing, improved traceability of eggs, best-before date, on-farm and packing station controls
Registered trademark with 85% egg producers registered
What are the hazards in milk and milk products?
TB, brucellosis, Salmonella, Campylobacter, Listeria monocytogenes, Staph aureus, Bacillus spp.
What process is used to destroy pathogenic bacteria in milk?
Heat treatments either pasteurisation or sterilisation
What are the potential sources of Listeria moncytogenes?
Infected animals, environment, silage, biofilms in food processing environment
What food sources are vehicles for Listeriosis food poisoning?
Chilled ready to eat food such as pre-packed sandwiches, pate, soft mould-ripened cheese, cooked sliced meats, smoked salmon
What are the clinical signs of listeriosis in humans?
Incubation period of 3-4 weeks but can be up to 90 days
Non - invasive form = flu-like symtpoms, often asymptomatic
Invasive from = Abortion, meningoencephalitis (in children, elderly and immunocompromised)
What are the three work streams of the FSA's Listeria Risk Management Program?
Targeting consumer behaviours and high risk groups
Provision of food to vulnerable groups has increased food safety
Industry compliance/enforcement by targeting high risk businesses and preventing equipment and environmental contamination
How does Bacillus cereus cause disease in milk?
Produces spores that survive pasteuristation
Grows at 5C and produces a toxin
How can you minimise the risk of Bacillus cereus food poisoning?
Why is Bacillus cereus poisoning uncommon?
Dairy products normally spoil before B. cereus contamination is sufficient to cause illness
How does Staphylococcal food poisoning occur?
Absorption of staphylococcal enterotoxins formed in the food
Outbreaks associated with consumption of cheese when milk was contaminated after pasteurisation
What are the biological food poisoning hazards in pork?
Aeromonas (spoilage pathogen)
What was established in 2008 to control Salmonella in pigs?
The Zoonoses National Control Programme for Salmonella in Pigs
What are the features of Yersinia enterocolitica food poisoning?
Very common in pigs where it causes very little or no disease
Found in undercooked pork, untreated water and unpasteurised milk
Usually resolves on its own but can be more severe in young and elderly people
What are the features of Hepatitis E food poisoning?
Increasing number of human cases
Recent case-control study identified consumption of processed pork products as risk factor
High prevalence in pigs in the UK
What are the biological hazards of food poisoning in beef?
E. coli O157
Aeromonas (spoilage pathogen)
How does E.coli O157 cause food poisoning in people?
Takes a low infection dose (<10 UFC)
Undercooked mince meat and direct contact such as open farms are common sources of infection
What are the clinical signs of E.coli O157 infection in people?
Diarrhoea, abdominal pain, vomiting, haemorrhagic colitis
Can cause HUS (haemolytic uraemic syndrome) in children and the elderly resulting in renal failure and death
What is the prevalence of E.coli O157 in UK livestock?
Up to 20% in cattle
How can E. coli O157 food poisoning be prevented?
What are the hazards associated with fish and shellfish?
Hepatitis A virus
Vibro spp. (raw seafood such as oysters)
How can the risk of norovirus food poisoning from oysters be managed?
Relaying = shellfish are harvested from a contaminated area and moved to a clean area for at least two months
Depuration = shellfish are placed in tanks of clean re-circulating seawater treated by UV radiation for at least 42 hours
What are the hazards associated with food poisoning and honey?
How does botulism occur?
Extremely potent requiring only 0.1-1ug and it is ubiquitous in the soil, sediments and water...
Found in home-canned vegetables, meat and fish as well as fermented bean and fish
What is the process of botulism infection in people?
Incubation time of 12-36 hours
Fatal outcome possible - need treatment with antitoxin
What are two examples of process hazards?
Staph aureus - intoxification, commonly from food handlers, bacteria contaminates product and produces toxin, high risk products are custards and whipped cream
Clostridium perfringens - intoxification, present in environment and raw meat, inadequate temp control during cooking may allow spores to germinate and bacteria to grow, stews are high risk products
What are some examples of industrial pollutants?
Heavy metal - lead, arsenic, mercury, cadmium
Halogenated hydrocarbons - PCBs, dioxins
What are some examples of agricultural contaminants?
Insecticides - Chlorinated hydrocarbons (DDT), organophosphates
What are some examples of growth promoters that may contaminate food?
Hormone-like GP (banned in EU)
Antimicrobial-like GP (banned in EU)
What are some examples of naturally occurring toxins that may contaminate food?
Biogenic amines - histamine, tyramine
Mycotoxins - alfatoxin, ochratoxins
Algal toxins, plant toxins - shellfish poisoning, mushroom poisoning
What food additives may contaminate food products?
Sensory additives - colour, emulsifier, sweetener, antiocidants, smoke
Meat conservation - nitrates, nitrites
Packaging - PVC
What does legislative framework involve at the level of industry risk management?
Lays down requirements for establishments handling, preparing or producing products of animal origin
What are the key areas to be considered in the risk management during the harvesting of milk?
Animal health and cleanliness
Milking area and milking process
Equipment, milk storage and staff
How does traceability improve risk mangement?
Can trace-forward and trace-back products to both recall and discover where an error was made
What is the microbiological criterion?
Defines the acceptability of a product or process
What is the Food Safety criterion?
Defines the acceptability of product to be put on the market
What is the role of the FSA in food risk management?
Enforce legislation, verification and auditing of meat premises and premises used for production of milk
Environmental Health Officers handle complaints through inspections, collecting samples and advising the community
What is the 4 C's strategy?
Promote safe handling of food in the home
Cooking, cleaning, cooling and avoiding cross-contamination
What factor is most often involved in outbreaks of food borne disease in Europe?
Which infection is proper refrigeration of pasteurised milk and dairy products critical to prevent?
In recent years which bacteria has been targeted by a national program across the poultry sector?
For which bacteria is good water quality important to prevent infection with?
What hygiene measures should be followed by personnel handling food?
Washing of hands
Wearing of gloves
Wearing of protective clothing
Wearing of hair nets