Food Safety: Surveillance 1

Front 1

What 3 methods convert isolates to culture?

Back 1

Phage-typing, antibiogram, sero-/biotyping

Front 2

What 2 methods convert culture to DNA isolation?

Back 2

Chemical analysis: FFA analysis, Maldi-TOF MS

Front 3

What also happens to culture and DNA isolation samples?

Back 3

library

Front 4

What 2 types of methods are used to analyze DNA isolations?

Back 4

PCR analysis and DNA fingerprinting / Sub-typing

Front 5

What 2 PCR analysis methods are conducted?

Back 5

Target gene detection, 16S rDNA

Front 6

What 8 methods of DNA fingerprinting / sub-typing are conducted?

Back 6

PFGE, RAPD, Ribotyping, RFLP-based typing, AFLP, MLST / MLVA, Genomotyping / Whole genome sequencing

Front 7

What scheme is used to help microbiological safety?

Back 7

HACCP

Front 8

What info is used to identify and control known pathogens?

Back 8

Culture methods, virulence, contamination, effects of food processing / preparation on survival, food consumption

Front 9

What 2 types of emerging pathogens are there?

Back 9

true emergence, re-emergence

Front 10

What does true emergence mean?

Back 10

New public health threat, rare

Front 11

What is re-emergence?

Back 11

New form, new infections

Front 12

What mediates the results of an infection?

Back 12

Host's immunological response and severity of infection

Front 13

What are 2 routes of infection?

Back 13

Entry through damaged surface epithelium, adherence to epithelial cells

Front 14

What happens after entry of infection through damaged epithelium?

Back 14

adherence to and colonisation of extracellular matrix, release of toxins, secretion of pro-inflammatory mediators, active inflammatory response

Front 15

What 2 events occur after adherence to epithelial cells?

Back 15

Replication on epithelial surfaces and colonisation, engulfment by phagocytic cells on mucous membranes

Front 16

What are the 2 outcomes of phagocytic engulfment?

Back 16

Destruction, survival and transfer to tissues

Front 17

What is the result of replication on epithelial surfaces and colonisation?

Back 17

release of toxins and activation of signal transduction pathways in host cells

Front 18

What happens after activation of signal transduction pathways?

Back 18

Secretion of pro-inflammatory mediators, invasion of epithelial cells

Front 19

When does localised infection occur?

Back 19

When infection survives phagocytes and transfers to tissues

Front 20

What are the 4 results of infection?

Back 20

Local tissue damage, toxaemia with altered cell function or structure, acute systemic disease, chronic disease

Front 21

What is the indicator for the sugars in peptone water test?

Back 21

Andrade's

Front 22

What test is used to identify streptococcus species?

Back 22

Sugars in peptone water

Front 23

What indicator is used for the triple sugar iron test?

Back 23

phenol red

Front 24

What test identifies salmonella species?

Back 24

triple sugar iron

Front 25

What is the indicator for the hydrogen sulphide production test?

Back 25

iron or lead compounds

Front 26

What test identifies salmonella and brucella species?

Back 26

hydrogen sulphide production

Front 27

What indicator is used for the decarboxylase test?

Back 27

bromocresol purple

Front 28

What test identifies enterobacteria?

Back 28

decarboxylase test

Front 29

What indicator is used for the urease test?

Back 29

phenol red

Front 30

What test identifies proteus species and corynebacterium renale?

Back 30

Urease test

Front 31

What are the iMViC tests?

Back 31

Idole test, methyl red test, Voges-Proskauer test, citrate utilisation

Front 32

What do the iMViC tests identify?

Back 32

Enterobacteria

Front 33

What is the cultural characteristic of E. coli?

Back 33

Some strains haemolytic

Front 34

Is E. coli motile or non-motile?

Back 34

motile

Front 35

Which pathogens ferment lactose?

Back 35

E. coli

Front 36

Which pathogens do not ferment lactose?

Back 36

Salmonella and Yersinia

Front 37

How E. coli react in the iMViC tests?

Back 37

Positive: indole, methyl red, lysine decarboxylase. Negative: V-P, citrate, H2S, urease

Front 38

How does Salmonella react to the iMViC tests?

Back 38

Positive: methyl red, citrate, H2S, lysine decarboxylation. Negative: indole, V-P, urease

Front 39

How does Yersinia react to iMViC tests?

Back 39

Positive: methyl, urease. Negative: V-P, citrate, H2S, lysine

Front 40

What test result varies for Yersinia?

Back 40

Indole

Front 41

Which Yersinia member is negative for the urease test?

Back 41

Y. pestis

Front 42

What are the 4 phenotype methods?

Back 42

Serotyping, Phage-typing, Antibiogram analysis, bio-typing

Front 43

What are the 4 steps of phenotypic methods?

Back 43

Pre-enrichment, selective plating, biochemical verification, serotyping

Front 44

What serogroup is Salmonella typhimurium?

Back 44

B

Front 45

What are Salmonella typhimurium's somatic (O) antigens?

Back 45

1, 4, (5), 12

Front 46

What are Salmonella typhimurium's flagellar (H) antigens?

Back 46

Phase 1: i

Phase 2: 1, 2

Front 47

What serogroup is Salmonella Enteritidis?

Back 47

D1

Front 48

What are Salmonella Enteritidis' O antigens?

Back 48

1, 9, 12

Front 49

What are Salmonella Enteritidis' H antigens?

Back 49

Phase 1: g, m

Phase 2: (1, 7)

Front 50

What does phagetyping use?

Back 50

standardised set of well-characterised lytic phages

Front 51

What does phage typing identify?

Back 51

Human and animal pathogens

Front 52

What happens during phage-typing?

Back 52

Pattern of susceptibility of bacterial isolate tested against panel of typing phages

Front 53

What is S. typhimurium's phagetype?

Back 53

DT104

Front 54

How are species identified in phagetyping?

Back 54

By using phages that lyse all members of a species

Front 55

How are sub-species identified in phagetyping?

Back 55

By using phages that lyse specific strains of a species

Front 56

What 3 strains are often phagetyped in food safety?

Back 56

Staphlococcus aureus, S. typhimurium, S. enteritidis

Front 57

What is phage typing used for in food safety?

Back 57

Identifying and tracing sources of food poisoning

Front 58

What are the 3 antimicrobial susceptibility tests?

Back 58

Disc diffusion, broth microdilution and E-test

Front 59

What is Maldi-TOF MS?

Back 59

Matrix assisted laser desorption / ionisation time-of-flight MS

Front 60

What is Maldi-TOF MS based on?

Back 60

Identification of organisms from their whole cell-MS

Front 61

How are bacterial cells prepared for Maldi-TOF MS?

Back 61

Using organic solvents and proteins crystalised after evaporation

Front 62

How many protein peaks are analysed in Maldi-TOF MS?

Back 62

70-200

Front 63

What are the 4 limitations of phenotypic methods?

Back 63

Many aren't universally applicable, variable gene expression and DNA mobility can lead to gain/loss of phenotypic traits, requires production and maintenance of large panels of reagents, some strains un-typable