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University Health Network

COVID-19 Cohort Study (CCS): Study of the epidemiology of COVID-19 in healthcare workers and their households

Information sheet for healthcare workers

Status: Not yet enrolling

Investigator/Study Doctor:  Dr. Allison McGeer, Microbiology & Infectious Diseases
Sponsor: Weston Foundation

Study Background/Purpose: The purpose of this study is to better understand how many people develop COVID-19 infection, how often infection is spread in households, and whether there are microbes or early immune responses (in our nose) that protect or make people more susceptible to infection.

The information we learn from this study will be used to inform recommendations about the particular importance (or lack thereof) of protective measures for people working in healthcare as well as Canadian households.

Who is being asked to participate:
People working in an acute care hospital who:
    • are 18 to 75 years old
    • work at least 20 hours per week (physicians and nurse practitioners who care for ill patients at least 8 hours per week are also eligible)
    • available for the next 3 months (not retiring or going on leave) and
    • have convenient access to a computer or a cell phone with internet access (to complete surveys and receive information about the study)

Study Visits and Procedures:
After consenting, healthcare workers are asked to:
    1) Do an online survey at enrolment to assess your current risk factors (~15 minutes)
    2) Complete short online surveys every week about whether you have had any symptoms (~2 minutes).  One week in five, the survey will be a bit longer and ask about your exposure to other ill people (~5-7 minutes)
    3) When you develop an acute respiratory illness (cough, fever, shortness of breath, excessive tiredness):
            i. Have a swab collected to test for COVID-19 at your workplace, your healthcare provider, or a COVID-19 assessment centre,
                1. inform the study that you have had a swab collected, and
                2. inform the study of the results
– OR - if you are at home when you become ill: collect your own nasal swab and send it to the study for testing (we will call you with the results); please do NOT submit swabs to more than one lab for testing as there are a shortage of swabs and test kits;
            ii. Complete online illness reports every day you have symptoms (~ 5 minutes for the first and ~2 minutes for all others);
            iii. You will be informed, by phone, of your test results
    4) If you agree (optional): provide blood specimens at the beginning and end of the study - to test for infections without symptoms. We will email you with details about dates and locations if you agree. If these dates do not coincide with a scheduled work shift, we will work with you to find one that does.

If you have others living in your home…we ask that you involve them in the study to help us measure risk factors for transmission within households. Everyone who sleeps in the same dwelling as you 3 nights per week, on average, is asked to participate.


If others in your home join the study, healthcare workers are asked to…
    • Do the 4 things listed above AND
    • Give us an email address to contact the adults who give you permission to share their email address with the study so we can send them an invitation to participate
    • Do a very short online survey about each child (about 2 minutes per child)
    • Complete weekly symptom reports for everyone in your home (about 1 minute per person)
    • Collect [or supervise the collection] of swabs to test for COVID-19 for ill children and complete illness reports for them (~ 2 minutes per day)
    • When someone in your home becomes ill, collect [or supervise the collection] of nasal swabs and pledgets (small absorbent papers put in the nose) for yourself and/or your children on Days 1, 3, 5, 7 & 10 to test for immune responses - to see if there are differences in the microbes in the noses of people who get COVID-19 and those who don’t. This is asked of ALL households where a person has COVID-19 and about 1 in 3 households where a person submits a swab that tests negative for COVID-19.

If others in your home join the study the adults (18 years or older) are asked to do…
    1) one baseline questionnaire (~5 to 15 minutes)
    2) an online report every 5th week (~5-7 minutes)
    3) when they develop an acute respiratory illness (cough, fever, shortness of breath, excessive tiredness):
            i. Collect your own nasal swab to test for COVID-19; and
            ii. Complete online illness reports every day they have symptoms (~ 5 minutes for the first and ~2 minutes for all others)
    4) when someone else in the home becomes ill, collect swabs and pledgets (small absorbent papers) on Days 1, 3, 5, 7 & 10 to test for immune responses. This is asked of ALL households where a person has COVID-19 and about 1 in 3 households where a person submits a swab that tests negative for COVID-19.