covid 19 3

The Grey Bruce Health Unit (GBHU) has developed a strategy for COVID-19 testing in workplace settings. In a July 9 media release, this strategy involves a series of COVID-19 tests on asymptomatic staff in an attempt to determine rates of infections in a controlled environment.

The first corporate participants to be tested under this strategy will be Bruce Power. Selection of the corporate participants was based on criteria related to risk of transmission in the workplace, impact of transmission, and practically of testing. The GBHU is in discussion with additional workplaces for their enrollment in this strategy.

Data from the strategy will be collated and analyzed as a feasibility study. As Ontario continues to successfully lift restrictions implemented to reduce spread of COVID-19, there is a directive from the provincial government for health units to make testing more widely available, including testing of asymptomatic people. There is some evidence of the need for serial testing, but no consensus yet on the frequency or interval for serial testing. Other relevant questions that remain unanswered lend themselves to learn how to optimize the process of testing to break the chain of transmission by examining an array of variables, including Independent test variables and Outcome variables.

Independent test variables:
i. Test iteration (for example: first, second and third tests in the series)
ii. Shift/time of day of work
iii. Participant’s department or type of work (for example: desk vs manual labour)
iv. Age group
v. Sex
vi. Live alone?
vii. Live with children?
viii. Household size (<>5?)
ix. Level of concern about COVID-19
x. Reason for concern

Outcome variables:
i. Rate of asymptomatic infection.
ii. Participation rate
iii. Time required to collect swabs
iv. False positive rate
v. Participant perception of value of test

“Testing is part of an overall strategy to monitor and contain the spread of COVID-19 and to optimize the response to the COVID-19 emergency," said Medical Officer of Health, Dr. Ian Arra. “Multiple questions are still to be answered about COVID-19 testing strategies. Such as the most effective frequency of testing in apparently healthy asymptotic people. Participation of staff at Bruce Power may help us answer some of these questions. In addition, this will provide the desired test results to these individuals.”

Staff from the GBHU will be on site at Bruce Power to provide testing to a large segment of their workforce. Participation is voluntary and only staff members who volunteer for the testing will be included. Employees will have the option of a single test or multiple tests over the course of several days.

If a volunteer tests positive, the health unit will contact them to guide them through the next steps. Most people who test positive will need to self-isolate, which means that they must avoid contact with others, including going to work. As with all potential exposures, the health unit will perform robust contact tracing and outbreak management, as required.

A full results of this study and subsequent analysis will be made public following the conclusion of this work. No date has been set for completion.

"We thank the volunteers for their valuable participation and Bruce Power for their commitment to health," read the release.

Another recent collaboration between the Grey Bruce Health Unit and Bruce Power led to the development of a dashboard that provides vital statistics over time with respect to COVID-19 cases in Grey and Bruce counties.

In a second media release July 9, the dashboard is available on the Grey Bruce Health Unit website at

The increased cumulative cases count allows for a more meaningful descriptive analysis of data. Information on the dashboard tracks daily and cumulative number of cases, as well as a breakdown of the age range, sex, and municipality of cases. Additionally, the percentage of cases by general population, long-term care resident and health care worker working in Grey Bruce are identified.

"We thank Bruce Power for their assistance in providing the technical framework and layout of the dashboard," read the release.