Foodborne Illness Flashcards
what are the main foodborne illnesses in the UK
The main diseases in these areas are measles, whooping cough, diptheria and scarlet fever- the numbers have went down
how many salmonella cases are there
Salmonella causes 2,500 hospital admissions
what are the annual sources of foodborne illnesses
poultry meat, vegetables, fruits, nuts, seeds and beef and lamb
what are the 2 types of foodborne illnesses
foodborne infetcions and intoxications
what are foodborne infections
foodborne infections= Living microbes needed and Growth in gut and damage to the host
what are foodborne intoxications
Toxin produced as a result of microbial growth, Ingestion of toxin needed to cause disease and Microbes may be absent or dead! More difficult to identify source and to trace it’s spread
what causes foodborne intoxications (bacteria etc)
-Fungi
-Algae
-Bacteria
-Most common type is ingestion of toxins in foods in which bacteria have grown- Staphylococcal food poisoning, Botulism and Clostridium perfringens food poisoning
what foods are at risk of Staphylococcal intoxication
meat and meat products, poultry and egg products, salads: egg, tuna, chicken, potato, bakery products: cream-filled pastries, cream pies, and chocolate eclairs, sandwich fillings and milk and dairy products.
what does Clostridium botulinum: botulism effect
-Affect nervous system - headache, vertigo, double vision, weakness, difficulty swallowing, progressive respiratory paralysis
-prefers no or low oxygen - produces toxin
-rare but very serious, often fatal or long-term recocvery necessary
-symptoms= double vision, difficult eye movement, swallowing and speech
where does Vegetarian and spore forms
found in soil, water, intestinal tracts of animals and fish
what do Clostridium perfringens cause
-Toxin-mediated infection= organisms eaten in food, stays in intestine and produces toxin
-mid-way between intoxication and infection
-Mild illness= Symptoms 8-22 hours
-Source= soil, dust, human and animal faeces
-Foods= cooked meats, chili, stews, poultry, gravies, baked beans, other thick dishes
what is Ergot
a fungal disease of rye grass. It transforms the grain into enlarged, hard, dark spur-like structures
where does ergot grow
It grows best in damp conditions. Variations in weather are therefor crucial for its growth. LSD, a popular street drug some years ago, can be extracted from ergot. (in an irony so frequent in medicine, ergot–a poison–is used to control excessive bleeding in childbirth.)
what is ergotism
is a form of fungal poisoning caused by the ingestion of the ergot fungus. It infects porridge and breads made from the grain. Ergot is best known for the two frequent extreme forms of the disease: convulsive and gangrenous. The reddening or blistering of the skin has earned it the occasional name of St. Anthony’s Fire
describe salmonella
-Gram negative rods, motile
-Facultative anaerobes
-Grows between 7-48 oC (opt. 37 oC), pH 4-8
-Killed by heat (72 oC for 15 sec.) and acid (pH 4.0 for 72 hr)
-Resists freezing and drying
what types of infections cause salmonella
Enteritis and Enteric fever
what are enteric fevers
-headache, malaise, high and persistent fever aches weakness, vomiting, abdominal pains and nausea
-low infective dose- 100s
-incubation period of 7-14 days
-infection can last weeks
-Invades gut epithelium cells and kills them
-Penetrates into bloodstream
-septicaemia after 10 days of infection
-antibiotic therapy needed
-Can have a long carrier state after infection
o Humans are the reservoir
o Salmonella typhi Typhoid Fever
o Typhoid Mary!
what is enteritis
-diarrhoea, abdominal pain, mild fever, chills, nausea and vomiting.
-incubation period 5-72 hr- infective dose of 106
-infection lasts 2-5 days
-Invades gut epithelium cells and kills them
-greatest severity in very young and very old
-can be fatal
-complications possible
-Reactive arthritis
-only treat symptoms
-Many different agents but all belong to a single species, S. enterica. Agents are subtypes of the species!
o Salmonella enteridis,
o S. typhimurium,
o S. Dublin
how are Salmonella that cause enteric fevers that are pathogens spread
-that are primarily spread among humans by the fecal-oral route.
-Contamination of food during cooking/preparation- Directly from food handlers –Clinical cases –Sub-clinical cases
-Also spread by sewage-contaminated water
-Control- Main controls are to provide clean water and adequate sanitation, antibiotics effective and vaccines available for short-term protection and limited protection for children
what is Campylobacter jejuni – campylobacteriosis
-headache, fever, fatigue, ab pain, diarrhea, vomiting. Sym may recur for several weeks
-Severe stomach cramps –can cause intense pain
-serious case of diarrhoea
–watery, slimy and is usually dark in colour –there may also be traces of blood
o Complications
–Arthritis
–Guillain-Barré Syndrome (GBS)
what is Escherichia coli O157:H7
-First recognized in 1982
-Infection and/or intoxication
-Causes severe illness/kidney failure/death
-Symptoms= abdominal pain, fever, cramps, nausea, bloody diarrhea - particularly harmful to children, elders
-Secondary infections caused by direct contact spread- Poor hand washing
-Source= intestinal tract of livestock, wild game,
-Association with food= minced beef, other undercooked meats, apple cider, water
what are the 2 similairites in norovirus and rotavirus
does not reproduce in food
how do we reduce foodborne illness (eliminate what)
-Eliminate the pathogen from the food
–Slaughter flocks that are salmonella positive
–Provide incentives for farmers to produce pathogen free animals- Pigs and salmonella
what is HACCP
HACCP is a way of managing food safety hazards. Food safety management procedures should be based on HACCP principles= microbiological - involving harmful bacteria, chemical - involving chemical contamination and physical - involving objects getting into food. Hazard Analysis and Critical Control Point
