Lecture 5 - Gastrointestinal Disease 1 Flashcards
What are the typical symptoms of gastrointestinal disease?
Vomiting
Diarrhoea
Fever
Abdominal pain
What is the difference between diarrhoea and dysentery?
Diarrhoea: no blood
Dysentery: blood, due to inflammation
Why will gastrointestinal disease cause death?
Due to fluid loss
What is the difference in prognosis of gastrointestinal disease in different parts of the world?
Developed world:
- self-limiting
- not life threatening
Non-developed world:
- can be life threatening
- leads to malnutrition, growth retardation
What is the definiation of a reservoir?
A living thing in which an infectious agent normally lives and multiplies
What are the main sources of infection for gastrointestinal disease?
Faeces Fingers Food Fluids Fornication
Discribe how the faecal-oral route may lead to infection?
Human / animal faeces contaminates food / water
Can people who aren’t presenting with symptoms of the disease be excreting the pathogen?
Yes
Which bacteria to poultry excrete?
Campylobacter
Salmonella
Which bacteria to cattle excrete?
Salmonella
E. coli
Which bacteria do pigs excrete?
Yersinia
How can we thwart faecal contamination of food?
Proper cooking techniques
Give some examples of how contaminated fluids can cause disease
Cholera: drinking contaminated water
Vibrio parahaemolyticus: oysters take in the bacteria
Giardia: swimming in contaminated water
How do ‘fingers’ play a role in disease?
They can convey microbes into the mouth
How may the habits of the food handler affect disease?
Normal flora from the handler can cause disease
What are fomites?
Inanimate objects with bacteria on them
What are the features of intoxication?
- Quick onset
- Not neutralised by cooking –> heat stable
- Mainly vomiting
What factors affect the likelyhood of bacteria surviving the GIT to cause disease?
- Use of antacids
- Dysbiosis
- Protection with food; chocolate, cheese
Which infections cause dysentery?
Shigella
Entamoeba histolytica
Which viruses cause watery diarhoea?
Cholera
Rotavirus
ETEC
If there is inflammation of the GIT, there will be…
Bloody diarrhoea
What is classed as long and short incubation period?
Short: 2-6 hours
Long: 12-48+ hours
Which pathogens have a low infectious dose? Why?
Shigella, it is acid stable
Which pathogens have a high infectious dose?
ETEC
Which specimens are used for investigation of gastrointestinal disease?
Faeces
Food
(Vomit)
Which lab procedures are used to investigate infections?
1/ Microscopy
- light, electron
2/ Latex agglutination, EIA (enzyme immuno assay)
3/ PCR, gel electrophoresis
