Food Poisoning

Question 1

What is food poisoning?

Answer 1

Illness caused by eating food contaminated with micro-organisms, toxins, poisons, etc

Question 2

What is the incubation period of Staph aureus and Bacillus cereus?

Answer 2

1-6 hours

Question 3

Staph aureus
Where?
How?
Symptoms?

Answer 3

Unrefrigerated or improperly refrigerated meat, potato and egg salads + cream pastries
Preformed toxins act on vomiting centre in the brain
Nausea + vomiting + abdo pain

Question 4

Bacillus cereus (Upper GI)
Where?
How?
Symptoms?

Answer 4

Improperly refrigerated, cooked or fried rice, meat
Heat resistant spores, starchy foods
Profuse vomiting

Question 5

What is the incubation time of bacillus cereus (upper GI)?

Answer 5

1-6 hours

Question 6

Bacillus cereus (Lower GI)
Where?
How?
Symptoms?

Answer 6

Meat, stew, gravy, vanilla sauce

Abdo cramps, Watery diarrhoea, Nausea

Question 7

What is the incubation time of bacillus cereus (lower GI)?

Answer 7

10-16 hours

Question 8

Clostridium perfringes incubation time?

Answer 8

8-16 hours

Question 9

C. perfringes
Where?
How?
Symptoms?

Answer 9

Meat, poultry, gravy, dried or recooked foods, time +/- temperature abused food
Toxins
Water diarrhoea, nausea, abode cramps, rarely fever

Question 10

Campylobacter (main C. jejuni)

Answer 10

16-48 hrs incubation
Sporadic
Poultry and raw milk / likely person-person
Pain, blood, fever

Question 11

Salmonella enteritidis

Answer 11

12-48 hours incubation
Poultry, meat, raw eggs
Animal gut, multiplies in food 
Toxins and invasion
D&V, blood and fever

Question 12

How do you treat campylobacter if significant co-morbidities?

Answer 12

Metronidazole

Question 13

What are complications of Salmonella?

Answer 13

Bacteraemia

Question 14

How is Salmonella typed?

Answer 14

According to O-antigen using slide agglutination

Locally groups B, C and D are common

Question 15

Complications of E. coli 0157?

Answer 15

Haemolytic Uraemic Syndrome

Question 16

E. coli 0157 affects?

Answer 16

Affect colonic cells and induce HUS

Question 17

How do you identify E. coli 0157?

Answer 17

Identify with EHEC

Question 18

Symptoms of E. coli 0157?

Answer 18

Bloody diarrhoea, blood per rectum

Question 19

How does E. coli 0157 cause an effect?

Answer 19

Produces shiva-like (aka vero-) toxin

Question 20

E. coli 0157 spreads easily because?

Answer 20

Very low infectious dose

Question 21

How is e. coli 0157 spread=

Answer 21

Beef, raw milk/water + wide range
Person-person; animal contact
Outbreak potential

Question 22

How does HUS present?

Answer 22

Abdominal pain
Fever
Pallor
Petechiae
Oliguria
Bloody diarrhoea

Question 23

Bloods for HUS?

Answer 23

Increased WCC
Decrease Plts, Hb
Red cell fragments
LDH > 1.5 x normal

Question 24

How do you investigate bloody faeces?

Answer 24

Stool cultures

Bloods: U&Es, FBC, film, LFT, clotting, urine, lactate, dehydrogenase

Question 25

On diagnosis of E. coli 0157/HUS you must notify?

Answer 25

Notify Health Protection Unit

Question 26

How does rotavirus spread?

Answer 26

Person-person; faecal oral
Direct and indirect
Usually seasonal to winter

Question 27

Rotavirus is usually subclinical in adults but can be severe if?

Answer 27

Immunocompromised

Question 28

What are the clinical effects of rotavirus?

Answer 28

Mild watery - profuse diarrhoea
Shock
May have moderate fever first then D&V
Not blood diarrhoea
Self-limiting
Lasta a week
Low infectious dose

Question 29

Key to treating food poisoning is?

Answer 29

Hydration

Question 30

How do you diagnose viral food poisoning?

Answer 30

PCR

Question 31

How does norovirus spread?

Answer 31

Faecal oral or droplet
Person to person (or on contaminated food/water)
Low infectious dose
Community reservoir
Asymptomatic shedding up to 48 hours past cessation of symptoms
Large outbreak potential

Question 32

How do you diagnose norovirus?

Answer 32

PCR stool or vomit

Copan viral swabs of vomit

Question 33

How do you treat norovirus?

Answer 33

Usually self-limiting - hydration

Question 34

Almost all children get norovirus before the age of?

Answer 34

5