Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ASII > Foodborne zoonoses and control > Flashcards

Foodborne zoonoses and control Flashcards

1
Q

What is zoonoses?

A
  • infections/ disease that are naturally transmitted between animals and humans
  • 60% pathogens = zoonotic
  • 75% of emerging infectious diseases have roots in zoonotic pathogens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are FBDs?

A
  • food borne disease
  • acute illnesses that are associated with the recent consumption of food
  • contain a pathogen/ toxin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the worldwide impact of foodborne disease?

A
  • 2.5 million deaths/year from diarrhoeal disease
  • 1.4 million cases of salonella - USA
  • $35 billion loss to economy
  • death of HIV patients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Difference between foodborne infection and intoxication?

A
  • infection - caused by an infection of bacteria etc
  • intoxication - toxin - more rapid onset
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are foodborne infections caused by?

A
  • pathogenic microorganisms infecting food, entering the body and the reaction of the body tissues to the pathogen
  • long incubation periods
  • fever
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

`Symptoms of food borne infection?

A
  • diarrohea
  • fever
  • sweating
  • cramps
  • nausea
  • vomiting
  • dehydration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the different types of food borne infections?

A
  • bacterial e.g. Salmonella, E.coli, Listeria
  • virus e.g. Hep A
  • Mycotic e.g. Candida spp
  • Parasitic - toxoplasma, protozoa, roundworms, tapeworms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Properties of Salmonella?

A
  • G-ve
  • rod shaped
  • anaerobic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 2 species in the genus (salmonella)

A
  • S.enterica
  • S.bongori - cold blooded
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How many serovars does S.enterica have?

A
  • 2,500
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 3 most common Salmonella causes of infections?

A
  • S.enteritidis
  • S. tymphimurium
  • S. Dublin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Incubation period of Salmonella?

A
  • 12-36 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How many organisms per gram do you need of Salmonella to cuase infection?

A
  • 1,000 -> 1,000,000
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How are Salmonella killed?

A
  • commercial pasteurisation - 85 degrees for 15 mins/ 4 degrees
  • not killed by freezing/ chilling carcasses
  • survive in moist earth - 1 year
  • in dry earth - 16 months
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

WHere do most outbreaks of salmonella come from?

A
  • eggs (50.5%)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How are developing eggs infected with salmonella?

A
  • transovarian transmission
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the properties of Campylobacter and which are the important human pathogens?

A
  • thermophilic - 41/42 degrees
  • microaerophilic
  • g-ve
  • spiral rods
  • C.jejuni and C.coli most important
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe Camp outbreaks

A
  • more sporadic
  • rare
  • but have low infectious dose
19
Q

What is the reservoir and incubation period of Camp?

A
  • reservoir - intestinal tract of poultry/wild birds
  • incubation - 2-5 days
20
Q

Symptoms of Camp?

A
  • watery, bloody diarrhoea, nausea, vomiting, headache, fever, abdo pain
  • self limiting
  • mod to severe
21
Q

In what groups in camp most common?

A
  • 65+
  • bowel cancer
  • proton-pumps
22
Q

What is the reservoirs and symptoms for Listeria?

A
  • reservoir = plant material and soil
  • 12.7% mortality
  • flu like, abortion, septicaemia, meningoencephalitis
  • incubation - 3-70 days
23
Q

Properties of E.coli?

A
  • only a few pathogenic strains
  • O.157 - pathogenic
  • linked to poorly cooked beef/ minced
  • part of normal gut flora
  • can be beneficial - Vit K
24
Q

What does enteroinvasive E.coli cause (EIEC)?

A
  • watery diarrhoea (bloody in under 10%)
  • abdo pains, nausea, headaches, fever
  • self limiting
  • 18 hours median
  • 10^8 bacterium needed
  • lasts 2/3 days
25
Q

What symptoms fo EHEC cause?

A
  • causes haemorrhagic colitis
  • bloody diarrhoea
  • vomiting
  • sometimes fever
  • incubation: 3-4 days
  • lasts 4-8 days - up to 13
  • O157:H7
  • hemolytic uremic syndrome (HUS)
26
Q

What do Yersinia and Shigella cause?

A
  • Yersinia - causes enterbacillae yersiniosis
  • 4 shigella species - dysentry - can be food borne or person to person
27
Q

How are food borne intoxications characterised?

A
  • short incubation
  • no fever
28
Q

Categories of food borne intoxications?

A
  • bacterial
  • fungal chemical
  • poisonous
  • plant
29
Q

How does S.aureus cause foodborne intoxication?

A
  • G+ve, fac. anaerobe, non-spore forming cocci
  • enterotoxins formed by the S.aureus (A,B,C,D,E)
30
Q

Nature of the enterotoxins?

A
  • temp stable
  • pH stable
  • enzyme stable - trypsin, chymotrypsin, renin, pepsin
  • not sensitive to irradiation
31
Q

How does S.aureus compete with other micoorganisms?

A
  • poorly
  • doesnt grow very well
  • so normally in foods where all other microorganisms gone - cooking etc.
32
Q

WHat are the vehicle foods and reservoirs for S.aureus?

A
  • milk
  • poultry
  • meat
  • shellfish
  • eggs
  • salad cereals
  • veg

Reservoirs:

  • mucous membranes of nasopharynx and skin
  • some in air, water, dust, faeces
33
Q

Disease symptoms of S.aureus?

A
  • nausea, abdo cramps, vomiting, salivation
  • 1-6 hours after ingestion of enterotoxin
  • lasts for 24-72 hrs
34
Q

Describe Bacillus cereus poisoning

A
  • G+ve, spore forming rod
  • produce heat stable toxins:
    • emetic
    • diaroheal:
      • haemolysis BL
      • non-haemolytic
35
Q

What are the vehicle foods of Bacillus cereus?

A
  • meat, eggs, dairy products
  • cereals - if not cooked and not chilled then spores can germinate, bacteria and toxins produced
  • re-heating does not kill toxins
  • spores not killed
36
Q

Symptoms of B.cereus in man?

A
  • emetic syndrome
    • nausea, vomiting, abdo cramps
    • 1-6hrs after diarrohea
  • diarrhoeal syndrome
    • profuse diarrhoea
    • abdo cramps
    • tenesmus
    • 8-16 hours after ingestion
37
Q

What Clostridiums cause food poisoning?

A
  • G+ve, spore forming rods
  • C.perfringens and C.botulinum - severe
  • C.difficile - antimicrobial chemotherapy - resistant
38
Q

What is C.perfringens and what does it cause?

A
  • g+ve, anaerobic, spore forming
  • soil, dust, sewage, marine sediments
  • spores can resist boiling for 4 hours
  • ingest vegetative cells
  • multiply in intestine and produce CPE
  • CPE = heat labile - 60 degrees for 10 mins
  • may be pre-formed - 1-2hours after
39
Q

Vehicle foods for C.perfringens?

A
  • meat, fish, veg, chicken, pork, fruits, spices
  • cooking = heat resistant endospores
  • cooling, warming - endospores germinate
  • food cooked one day then eaten the next
  • anerobic conditions increase this
  • need to reach 10^7/8
40
Q

Symptoms of C.perfringens?

A
  • nausea, vomiting, diarrhoea, cramps
  • 6-24 hours
  • 1-2 days duration
  • needs to reach 5 x 10^8 cells
41
Q

What does C.botulinum cause?

A
  • obligate, anaerobic, spore forming bacillus
  • spores -> vegetative cells -> enterotoxins
  • poorly canned/ bottled - honey
  • enterotoxins - blocks synapses - paralysis and death
  • Toxins - A, B, E, F, G
  • spores - survive 120 degrees
  • Heat liable toxins - 80 degrees for 10 mins
  • resists action of gastric and intestinal juices
  • any foods associated with anerobic conditions - cooked meats (canned), fermented foods
42
Q

Symptoms of botulinum toxins?

A
  • paralysis
  • nausea
  • double vision
  • respiratory failure
  • headache
  • lack of fever
  • great muscular weakness
  • fatigue
  • 60-100% mortality
43
Q

duration of botulinum illness?

A
  • 1-10 days
44
Q
A

ASII (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions