Food borne Diseases Flashcards
What factors affect microbial growth in food?
Heat, water availability, nutrient content, resistance to decay
Name an antimicrobial agent?
Garlic can act as an anti microbial agent as it produces Allicin which makes it difficult for bacteria to break down
Identify the features that the host has to protect them against foodborne diseases?
And acidic stomach, proteolytic enzymes, bile salts, rapid flow of material for the GI tract, microflora in the colon, rapid cell turnover
What is meant by the term infective dose?
This is the amount of pathogen that will be required to cause an infection. This will vary widely between individuals depending on the infectivity, you may not always need a high number of microbes to cause an infection if there is a high infectivity
Give four examples of bacterial foodborne diseases
Campylobacteriosis, salmonella, E. coli, listeriosis
What does campylobacteriosis cause in terms of symptoms?
Food poisoning, localised tissue damage
What is a common source of campylobacteriosis ?
Chicken
What is the structure of campylobacteriosis?
Microaerophilic, curved morphology, adhesins adhere to intestinal mucosa
How does salmonella cause infection?
The fimbrae of the pathogen adhere to intestinal mucosa and then invade epithelial cells of the small intestine producing toxins which stimulate and immune response, as the microbial load increases
A secondary infection of salmonella can be fatal
Which meat product is E. coli associated with?
Beef, serotype 0157 is the most common.
What happens to your body if infected with E. coli?
Severe stomach cramps, diarrhoea, vomiting. Complications may include hemorrhagic colitis and haemolytic uraeic syndrome
What are the sources of listeriosis bacteria?
Soft cheese, unwashed vegetables, vacuum packed food
Who is listeriosis most dangerous to?
Pregnant women, neonates
What are two examples of preformed toxins in food?
Bacillus cereus can survive after the cooking process, especially if the food is stored improperly Staphylococcus aureus can be contracted from poor hand hygiene
