Home > Infectious Diseases > Canada Communicable Disease Report (CCDR) > 2014 Volume 40 > CCDR: Volume 40 S-1, October 9, 2014 > Text Equivalents
Figure 1 is a histogram identifying the number of confirmed outbreak cases of E. coli O157:H7 by symptom onset date and province, December 2012 - January 2013. There were 31 cases. The symptom onset of the first confirmed case was December 22 in New Brunswick. The symptom onset of the last confirmed case was January 24, 2013 in Nova Scotia. The greatest number of cases noted for a single day was December 23, 2012 with 4 cases reported from New Brunswick, 4 from Nova Scotia and one from Ontario. The second greatest number of cases in a single day was December 26, 2012 with 4 cases from Ontario and one case from Nova Scotia. There were 1-3 cases per day between December 27, 2012 and January 5, 2 013 except on January 1,4, 6-8 and 10-23 when no symptom onset of cases were recorded. There was an asterisk above the single case in Ontario for January 5, 2013 and the single case in Nova Scotia on January 24; a footnote for the asterisk explained that secondary transmission cannot be ruled out for these cases.
This figure has one main box highlighting the criteria for the review of provincial enteric disease alerts and clusters and then three smaller boxes that identify the need to review and two options. In the main box it notes that either 3 criteria are met, namely: 1) a minimum number of cases which could be 2-5 cases of a pathogen with common serotype/species with further typing or rare serotype/species or 5-10 cases of a pathogen with common genus/serotype/species without further typing, 2) a maximum time range defined as the earliest of available dates (report date, collection date or onset date) of most recent case within 14 days of notification date and 3) a geographic distribution that is defined as multi-regional or unknown or it could be one of three exceptions: a single case of botulism, any number of cases with earliest of available dates (report date, collection date or onset date) within 14 days of notification date with an epidemiological link to each other, a food or common source, or any number of cases associated with investigations initiated by other jurisdictions. The next box is to review and then two boxes identify the subsequent options: Exclude alerts or clusters associated with travel/immigration, a single health region, a data entry error or previously investigated or Report and investigate where the level of investigation is based on the pathogen and available information.