food/drink questionnaire

You have just finished administering a food/drink questionnaire to ill and non-ill participants in a Minnesota summer picnic party. The ill individuals developed moderate to severe diarrhea 16 to 46 hours after the picnic. Six persons experienced vomiting. The following data were collected:

ATE

DID NOT EAT

Number of people

Number of people

Food item

Ill

Not ill

Total

Ill

Not ill

Total

Hot dogs

40

30

70

10

20

30

Hamburgers

32

8

40

20

40

60

Potato salad

45

25

70

15

25

40

Ice cream

48

12

60

2

38

40

Lemonade

20

40

60

20

20

40

Which food item appears to be the most probable vehicle for the salmonella (agent) infection associated with the illness?

Hot dogs

Hamburgers

Potato salad

Ice cream

Lemonade