Epidemiological information: Outbreak of E.coli infections
October 5, 2015
Related Public Health Notice
What is epidemiology?
Epidemiology is the study of disease in a population. Epidemiologists, or "disease detectives," use surveillance systems to identify those who are sick and confirm that the sick people are part of this event. They then gather information from the people who got sick and review the clues from all parts of the investigation that might reveal the cause of the illness event.
The figure below forms part of the epidemiological investigation into this outbreak. An "epi curve" (Figure 1) is a valuable reference tool in any epidemiological investigation. An epi curve shows when cases begin, when they peak, and when they trail off. Certain details of the people who got sick (Table 1) also help epidemiologists as they work to solve the questions involved in foodborne illness.
Figure 1. Number of people infected with the outbreak strain of E. coli*
* Information available for 29 of 29 cases
Text equivalent for figure 1
Table 1. People confirmed to be infected with the outbreak strain of E. coli O157, by illness onset or specimen collection date
| Illness onset or specimen collection date | Number of cases |
|---|---|
| 12-Jul | 1 |
| 17-Jul | 1 |
| 26-Jul | 1 |
| 27-Jul | 1 |
| 28-Jul | 2 |
| 29-Jul | 4 |
| 30-Jul | 2 |
| 31-Jul | 4 |
| 01-Aug | 5 |
| 04-Aug | 1 |
| 05-Aug | 2 |
| 07-Aug | 1 |
| 17-Aug | 1 |
| 19-Aug | 1 |
| 20-Aug | 1 |
| 28-Aug | 1 |
Note: It can take several weeks from the time a person becomes ill to when this illness is reported and testing confirms a link to the outbreak.
| Outbreak status | Ongoing |
|---|---|
| Case count | 29 |
| Provinces/Territories | 4 |
| Hospitalizations | 7 |
| Deaths | 0 |
| Gender (m:f) | 15:14 |
| Age range in years | 1-77 |
| Recall | No |
* Information available for 29 of 29 cases