In her weekly segment with CP24, Dr. Eileen de Villa, Toronto's medical officer of health, answers viewer questions about COVID-19, including vaccines, variants, and the latest public health measures.

CP24: Two of the biggest school boards in the country are in Toronto. How much have you been in discussions with the two boards around the back-to-school plan? We know that the province will reveal its plans next week. Can you give us any hints?

De Villa: I'm not going to steal any of the thunder of my provincial counterparts. And as you know, education is really within their purview. Of course, local public health units have a role to play. We are the primary partners from a public health perspective when it comes to interactions directly with the school boards, and of course, we have a vested interest in the health of the youngest members of our communities. So, I can assure you that my team here at Toronto Public Health has been in regular conversation with provincial counterparts, both in terms of health and in terms of education. We are always in conversation with our school board partners. And of course, we are united in our objective of ensuring the safest, healthiest possible environment for the students at school and, of course, for all those who are there to support them in their learning -- teachers and all the staff that it takes to run a school board and individual schools effectively.

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CP24: How concerned are you, if at all, about children under 12 being vectors for transmission? They can't be vaccinated. Do you feel comfortable enough for the full reopening, knowing that there are kids at school without any protection?

De Villa: If you listen to COVID-19 press briefing 186, you would have heard me say that, of course, I am concerned about young people. They're one of the populations I think about. I think about all those who are unvaccinated in our city, recognizing that they are at risk. They are at significant risk, particularly with the presence of the Delta variant. But there are also those in our community who are unvaccinated because they can't be at this point. And that includes children under the age of 12. We hope to have that opportunity to vaccinate them as more studies are made available and as the available vaccine products become licensed for them. Hopefully, that will come in a few months. But until then, the best thing we can do together as a community is to ensure that all of us are eligible to get vaccinated right now, that's everyone 12 years of age or older actually goes and gets the vaccine and gets fully vaccinated with both doses of a licensed COVID-19 vaccine. That's what we can do to best protect our community, but in particular, to protect those under the age of 12 who can't get vaccinated quite yet.

CP24: Earlier, you talked about shifting the vaccine strategy from mass vaccine clinics to hyperlocal sites. Is this exactly along the lines of how the city plan to roll things out all along? Or have you sort of had to go back to the drawing board to try and find the unvaccinated or the vaccine-hesitant?

De Villa: I think this was exactly what we had anticipated. I mean, nobody ever really knows at the outset how things are going to go. But when it comes to vaccination campaigns like the COVID-19 vaccination campaign, we had always imagined even from the very beginning, that in the first instance, it made sense to have large mass immunization clinics that people would attend, like they would actually have to come to in order to get vaccinated. But it is fairly typical in these large-scale vaccination campaigns. that at some point, as you get into the last percentages of the population that have yet to get vaccinated that you need to change your tactics and that you really have to take the best efforts to bring the vaccine closer to those individuals, closer to those communities that have more challenge or more difficulty getting access to vaccine and haven't gotten it yet quite yet. So, that's exactly what we're going to do. The idea is to drop the barriers to the greatest extent possible, make it as easy as possible for those who haven't gotten vaccinated yet to do so in order to protect themselves and to protect the rest of us as a community.

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CP24: Globally, some countries like Australia and the United States are seeing a surge of cases due to the delta variant. While most Torontonians are now vaccinated, how concerned are you about the delta variant?

De Villa: Where we are seeing Delta being able to take its greatest effect and have the most significant impact is in those places and with those people who are either unvaccinated or not fully vaccinated. And as I mentioned earlier today, we are so, so lucky here in Canada, and specifically in Toronto, that we have access to these vaccines, and we have been able to cover a significant proportion of our population. So certainly, we have a great deal of protection. But you know, I think it still warrants some caution. We don't understand absolutely everything about this new variant, as is the case with all new emerging variants. So, we need to make sure that we continue the efforts to get our vaccination rates as high as we can get them. And I would advise people to still practice those public health measures. Be cautious, be careful. We're still very much in the learning phase with a new virus. Again, I know it feels like we've been living with COVID-19 forever, but it was only discovered a year and a half ago. So, still much more learning to do. Let's use the knowledge we have. And let's make sure we're getting vaccinated. That's the best protection we can provide for ourselves in our community.

CP24: A viewer says Dr. Moore, Ontario's chief medical officer of health, said there would be different rules for unvaccinated and vaccinated students and staff. The viewer wants to know how schools will know who is vaccinated and who is not.

De Villa: That is an excellent question, and I think one for which we may have to wait until we see that provincial plan until we know the full answer. Clearly, knowing the vaccination status of individuals, both staff and students will have some clear advantages. Certainly, if there is a case within the school, it is much, much easier to manage from a local public health perspective when you know who is fully vaccinated and who isn't. And therefore, who's at greater risk, especially when we're talking about something like the Delta variant, which we know through all the reports right now, is clearly far riskier when we're talking about somebody who is not yet vaccinated. So again, I cannot say enough how important it is that people go and get vaccinated. They're safe. They're effective. And there are hundreds of thousands of us who are now enjoying the protection of these vaccines. It is truly if you've had that experience, it feels really great to have the protection afforded by the vaccine. I encourage people to go out and seek that opportunity for themselves if they haven't already done so.

READ MORE: Ontario will have different rules for vaccinated students and staff in the event of school outbreaks, top doc says

CP24: Before COVID-19, kids already need to show proof of vaccination to go to school. Shouldn't it be easy to identify at least children's vaccination status? At least from an educational perspective, we should know which children are vaccinated, and that part of it should seem to be mandatory.

De Villa: Well, and again, I think we'll look forward for sure to hearing what's in the educational plan put forward by our provincial counterparts. I know that there has been much discussion on this. And certainly, a lot of thought and reflection has gone into this. So, we'll look forward to seeing their plans and certainly know that there are many of us who are absolutely committed to doing the very best we can to create those safe environments within our schools. We know how important that in-person education is to our children. That's been proven time and time again through the available science and research. So, again, what can we do? The more we are able to control disease transmission within our community, the vaccine being a key part of that, the better able we will be to ensure a safe school environment for our children to return to this fall.

CP24: A viewer asks, how many children 12 and under are testing positive daily? Should we be concerned that it will now move into that population because none of them are vaccinated?

De Villa: That is a very legitimate concern. And that's exactly the reason why I think, and I worry a little bit about our young people. And again, it always comes back to the same message. As it turns out, the more we are vaccinated, the more that those of us who are eligible to receive vaccine actually go out and get fully vaccinated, the safer our children will be until such time as they are eligible to then go and get vaccinated. And we are extremely hopeful that the studies are being done by the vaccine manufacturers who are doing the trials they need to do to get their products licensed for a younger population. Certainly, I understand that the data are promising. And so, we're very, very hopeful that we should have some vaccine products available either later this year or early next year for a younger population, those younger than 12, so that they can directly benefit from the protection of vaccines.

CP24: Have you heard anything doctor about rapid testing for schools? Is it something you would advocate for in the classroom?

De Villa: I think that there's been a lot of conversation throughout the course of the pandemic around how do we make testing more accessible to help support infection prevention and control efforts. I don't have any specific information available for you today on that, but I know that there are a number of different testing methods being explored. And I imagine that we may hear something from our provincial counterparts as part of their plan, all aimed towards creating that safe school environment.

CP24: A fully vaccinated viewer who is also on immunosuppression therapy and works in a restaurant wants to know if he should be looking for a third dose this fall when everyone moves back indoors.

De Villa: This is still very much the subject of ongoing discussion. I know that those who are involved in providing guidance around vaccines and how best to use them to the greatest effect and in a safe manner are actively looking at these questions. So again, with apologies to the viewer, no specific answer at this time around a third dose or a booster dose. But please know that that question is actively being looked at. And as soon as we have information, we'll be sure to share that with you, along with all the other people who, for a variety of reasons, maybe immune-compromised or immune-suppressed medical conditions, medications that people have to take. This is not entirely uncommon in our city, but it speaks again to the need for those of us who can get vaccinated and practice good public health measures. For those who are immune-compromised or immune-suppressed, you're going to want to use absolutely vaccination as the first layer of defence. But again, where possible, keeping distance, wearing your mask, trying to be in outdoor environments as much as possible if you're going to have contact with others whose vaccination status is not entirely clear to you. These are the kinds of steps that you can take to best protect yourself. So, I would encourage people in the viewer's circumstances to keep informed, keep listening as the new information comes out and, of course, continue to practice those public health measures.

CP24: Another viewer says he got AstraZeneca for his first dose and Moderna for the second dose. He wants to know if he can get a third shot of Moderna because he wants to travel, and some countries do not recognize mixing and matching vaccines.

De Villa: I will say that, and again, still not yet a definitive answer on this. We know that this is an issue, certainly way above my paygrade if we can describe it that way. This is something that I know our federal partners are actively looking at. And this is a concern, not only for us as a nation, but frankly, for nations all over the world. So, there are conversations happening to try to get to some degree of standardization so that movement can resume. We know that lots of people want to engage in leisure travel, and of course, there is work or essential travel that has to continue. It would be very helpful as the international community sort of wraps their heads around this to figure out what a standard method is. And what we will use as international standards to demonstrate appropriate coverage with the COVID-19 vaccine. So, I'll have to ask the viewers to stay tuned and please know that this question is one that people are fully aware of and actively engaging.

CP24: A viewer says the population will never achieve 100% vaccination, and the virus is sure to be round in some form for years to come. He asks, what benchmarks will allow us to return to most of the freedoms we enjoyed before COVID-19? Do you foresee any restrictions that are here to stay?

De Villa: This is one of those difficult questions that ask us to try and think and predict the future. When it comes to something like COVID-19, and we've seen with this particular virus that with continued transmission and with continued spread from person to person, we are seeing the emergence of variants like the Delta variant. This is just the latest of many variants of concern. So, it's very, very difficult to predict the future. I would say this. There's no question we don't anticipate that we will ever get to 100% vaccine coverage. I think that as much as we will strive for the highest level of coverages, we can get, I don't know that one ever gets to 100% coverage. But certainly, what we try to do is get to the highest level we can. The higher we are able to take that vaccine coverage, the more that protective benefit, the less opportunity COVID-19 is afforded to take hold and transmit from person to person. So, I think it does come down to that. I do think that the more we are able to get higher vaccine coverage rates, the more we are able to reduce transmission within our community, the more likely we are to find ourselves in a situation where perhaps we get to life as it was before there was a COVID-19 without the restrictions and the safety measures in place. But in the meantime, it is all about getting vaccinated, and it continues to be about practicing public health measures as best as possible, particularly in higher-risk settings, indoor settings, where there are other people congregated together and where you're not clear about the vaccination status of other individuals.