OMA Spotlight on Health

COVID-19 Contact Tracing with Dr. Chris Mackie

June 12, 2020 Ontario Medical Association Season 1 Episode 20
OMA Spotlight on Health
COVID-19 Contact Tracing with Dr. Chris Mackie
Show Notes Transcript

What is contact tracing and why is it so important as we reopen Ontario? This episode features Dr. Chris Mackie, the Medical Officer of Health and CEO for the Middlesex London Health Unit, as he explains the role of contact tracing in preventing the spread of COVID-19. 

OMA Podcast Episode 20: COVID-19 Contact Tracing with Dr. Chris Mackie


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Voice-over: In this podcast the Ontario Medical Association looks at current health issues that are on everyone’s mind. Spotlight on Health gives you the straight talk. We’re Ontario’s doctors and your health matters to us. 


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Anne Marie Flanagan: I'm Anne Marie Flanagan, and I'm the Director of Media Relations and Social Media for the Ontario Medical Association.


Dr. Chris Mackie: Dr. Chris Mackie Medical Officer of Health and CEO at the Middlesex London Health Unit.


Flanagan: We're here today to talk about contact tracing.


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Flanagan: Dr. Mackie, what is contact tracing?


Dr. Mackie: The role of public health in most infectious diseases is to prevent future cases. So when a case is diagnosed an infectious disease like coronavirus, the treating physician will be responsible for the care of the patient. 


Now public health gets notified, and we're responsible to try and prevent spread to other people. Case management is a major part of that, and contact tracing and contact management is another big component.


Contact tracing would be working with the case, the individual diagnosed to identify anyone that they've had close contact with in the preceding, in this case, seven days or so, which would be potentially the times when they were able to communicate the disease even prior to symptoms.


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Flanagan: Why is contract tracing so important?


Dr. Mackie: Contact tracing is crucial. It's all about containment of the illness. Once you've identified a contact who has had a significant exposure to the case, then you make sure that they're self isolating at home, even from family members, and that helps prevent the future spread. With something like this COVID-19 coronavirus, we know that people can spread the virus before they have symptoms. That's why it's important to isolate those contacts, even before they get sick.


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Flanagan: How is contact tracing generally done?


Dr. Mackie: In general, we do contact tracing over the phone. Most of the times the case can provide contact information for that contact. It may be that we have to be in touch by email or even through social media in order to get that phone contact, but having a live conversation with the contact is really important.


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Flanagan: Is there a way people can help with the contact tracing? Is there a way that they could prepare?


Dr. Mackie: The biggest thing that people can do to help to with contact tracing is minimize the number of contacts they have in the community.


But we know that people are going to be in contact with people who they live with. But, the more you can minimize how many other people you have contact with, the more we can reduce the spread of COVID, even before any diagnosis in your family or community is made.


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Flanagan: And I believe, doing contact tracing, you're usually looking to identify individuals that the person's had contact with for 15 minutes or more, and then particularly within that two metres distance. Is that correct?


Dr. Mackie: That's right. When we're looking at significant contacts, you need to have an exposure that is more than just sort of walking by somebody in a grocery store, which is the sort of really minimal exposure. Obviously we want to keep our distance—physical distancing of six feet or more is really important—but just walking by somebody who is sick is generally not considered a significant exposure.


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Flanagan: My understanding, as well, is that outside exposure is a little bit less dangerous than inside exposure as well, right? The spread isn't quite as likely if you're outside?


Dr. Mackie: It's really anywhere with good airflow. The droplets get dispersed pretty quickly when you're outdoors, and so the concentration of droplets that the person might be in contact with doesn't usually reach the level to make the illness communicable. You have to have a sufficient inoculum of the coronavirus in order to get infected.


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Flanagan: Contact tracing. We've talked a lot about it, and people have probably heard about it more recently than they've ever heard before, but it's not new, right? It's something that's been in use for a long time with other infectious diseases?


Dr. Mackie: Contact tracing is bread-and-butter public health. This is what we do 24/7, 365. Whenever there's a significant case of illness—whether it's meningitis, suspected case of Ebola, or even some less serious illnesses—contact tracing is a big part of public health. It's a big part of how we contain the spread of diseases in our community.


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Flanagan: With a newer illness like COVID-19, does it potentially, in the long run, play a part in the knowledge base on the illness and the research?


Dr. Mackie: Identifying cases and preventing additional cases are the most important components. It's also part of building the knowledge base because, as we understand which contacts are significant and more likely to become infected, that can help us to put recommendations or other control measures in place to prevent spread.


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Flanagan: Just wanted to ask about the role of a Medical Officer of Health and the public health unit because, I think, recent times there’s been a lot more media attention about that, and people might be familiar with the role that their family doctor or other specialists play, but maybe they're not as familiar with the role of a Medical Officer of Health. So could you talk about that a little bit?


Dr. Mackie: The biggest thing about Medical Officers of Health is that our role is really as team leader. We work closely with public health inspectors, public health nurses, epidemiologists, all sorts of other professionals, to make sure that we're doing everything possible to protect our communities from infectious diseases and also in normal times all sorts of other diseases, chronic diseases, cancer, etc.


And the role is only doable in a team environment. It's not generally me or my associate Medical Officer of Health Dr. Alex Summers, for example, who are making those contact tracing calls. It's usually public health inspectors or nurses. 


We've actually had a number of medical students involved over the last several months as well. Once clinical clerkship rotations were cancelled, we had 60 Med 3/Med 4 students from Western University come and join our case and contact management team. So that's been incredibly helpful.


But, our roles include surveillance, so monitoring for infectious disease and reporting to the public on it, case and contact management, obviously. We also are involved in public health measures and public health recommendations, whether it's working with partners on infection control issues, or issuing orders to individuals, classes of individuals, businesses...


We have pretty broad powers under the Health Protection Promotion Act. In the last version of the pandemic, we've been quite involved in testing of individuals for coronavirus. 


That's not usually a public health responsibility, but there was such a gap that public health was asked to step in and help with testing, to set up the assessment centres, which are the high volume flow testing centres.


And then, the other place where public health is often used in pandemic, is where there is short supply of testing, for example, or a vaccine during the H1N1 pandemic. Because public health is seen as a professional, credible organization that can really make sure that those resources get to those that need the most first.


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Flanagan: I noticed on the Middlesex London Public Health Unit’s Twitter account that you've been providing updates in terms of wait times at the COVID assessment centres. Have you gotten any feedback on that?


Dr. Mackie: Well the feedback is that people show up and get tested, and that's what we need. That's incredibly helpful when people put themselves out. Getting tested is a huge part of identifying cases and controlling the spread of COVID.


The assessment centres were something that public health was asked to develop in partnership with the hospitals, and so we've done that here in London.


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Flanagan: I wanted to ask about the role of social media in a pandemic like this. It's really changed, obviously, and I think there's been some positives and negatives. What's your opinion on that, and what do you see as the positives and negatives?


Dr. Mackie: I use it in two ways. 


First of all, to get information out quickly in an unfiltered way, making sure that people hearing straight from the Medical Officer of Health, straight from the public health unit.


The other way is to really understand what my community is thinking about, worrying about, and asking questions about. I try to engage in social media in a transactional way, so that I'm not just putting information out, but also receiving and hearing from people and community. So we might hear about a problem with a business that might be operating inappropriately. Or, “Question: Can I take my kids to the cottage?” “Can I go outside for a jog?”


Those questions are really helpful to know what's on the mind of our community. I would say the social media role, though, has its limits. Obviously, inaccurate information can be easily spread, but more importantly, social media has a limited reach. There are only certain people that are using it in certain ways.


And so you might have lots of people in your community using social media, but not looking for public health information.


It's crucial in my mind to recognize that social media does not replace the formal media—the large broadcasters, local newspapers, everything in between—have been crucial for getting out the public health messaging related to the coronavirus pandemic.


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Flanagan: What has been the thing that you've been really pleased to see, or has surprised you the most in this time? I know we hear a lot about the cooperation between different healthcare professionals, and how a lot of people have really come together in very difficult situations. Do you have any particular examples of that, that you might want to share?


Dr. Mackie: Public health has been asked to get involved in overseeing the healthcare response. I've been very impressed with how the hospitals, the labs, long-term care, other partners, have really worked together, particularly when we have issues around the long-term care home or retirement home that needs support.


To see the system rally like that. I mean, I think the amount of collaboration that's happening right now at the institutional level is more than what we've ever seen in Ontario. That's a real positive.


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Flanagan: Is there anything you would say to people—it gets difficult for folks being stuck at home over long periods of time, and while things are opening back up a bit, I know the recommendation is that people still be careful and minimize contact. And what would you say to folks that are starting to feel a little bit frustrated about being at home?


Dr. Mackie: I would just say to pay some attention to how you can keep yourself safe, even as you do open your life up again.


Meeting neighbours, but keeping your distance. If you're going to have family members over, maybe think about not sharing food, not sharing gifts. Finding a way other than hugs and kisses to greet family members. At least while we finish off the last of this pandemic wave.


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Voice-over: This podcast is brought to you by the Ontario Medical Association. It is produced and edited by Jodi Crawford Productions. This podcast is not intended to provide medical advice for specific situations and is for general educational purposes only. Please consult your doctor if you have symptoms or questions about your health.


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