Foodborne Outbreak
The Foodborne case study is due in two weeks on Sunday, March 7th by 11:59 pm. Below are case study tips that many students find to be very helpful.
Gastroenteritis Outbreak Findings by Person, Case Distribution
by Age and Gender
| Females | Males | Total | ||||
| Age Group | No. | % Female (in age group) | No. | % Male (in age group) | No. | % |
| 0-5 | 1 | 50% | 1 | 50% | 2 | 1.85% |
| 6-10 | 52 | 55.32 | 42 | 44.68% | 94 | 87.04% |
| 11 and older | 8 | 4 | 12 | |||
| Total by Gender | 61 | 47 | 108 | |||
I find that most students have issues with the first table on the Foodborne case study. The basic formula is Formula: Number of females/Total number in that age group…52 (total number of females in age group 6-10)/94 (total number for female and male in age group 6-10 combined) x 100 = 55.32% Male age group 6-10= (42/94) x 100 = 44.68%
94 (total number for age group 6-10)/108 (total number by gender) x 100= 87.04
Use the same formula for each age group. I can look over your case study if you wish to email to me prior to due date.
There will be a lot of AR calculations in the next case study. Remember the formula is: ill/ill+well (total attended) x 100. Also round your answers to the nearest hundredth to receive full credit. Example:
Food item: Meat Loaf
Total ill: 5
Total ill and well: 62
5/62= 0.08064516 x 100= 8.06451613 then round to the nearest hundredth which would make the answer 8.06.
AR: 8.06%
**Same formula for the those who did not eat the food item**
Also, make sure to provide an answer when you see the words ‘Interpret your findings‘. This would include a statement of the magnitude of the effect based on the rate ratio (or relative risk [RR]). There is a handout in the Chapter 7 folder on the use of RR in a foodborne (E. coli) outbreak. Review that before working on this case study.
You will calculate RRs for place and then food items. So, if one of the foods had an RR of 3.92, your interpretation of the RR would be that “those who ate that food were nearly 4 times more likely to have gastroenteritis”. If any of the RRs are well below 1.0, that would mean the food was protective of gastroenteritis ~ meaning those who ate that item were less likely to be ill. For example, if an RR for a food was 0.32, you could state that “those who ate that food were 68% less likely to have gastroenteritis”. You find the % by subtracting the lower RR from 1.0.
Lastly, for this case study and all other assignments that have numerical answers, round your answer to the hundredths. This applies to the Attack Rates and the RRs in the case study. If the calculation gives you 2.679, put down 2.68 instead of 2.7 or 3.0.
