TORONTO -- "The holidays in 2020 pose a real threat."

This is the warning from Toronto’s top doctor on Wednesday after the city reported a record-high of new COVID-19 cases.

During the city’s COVID-19 briefing, Dr. Eileen de Villa said people are not staying home as they did during the first lockdown in spring, which is contributing to the spread of the virus.

Toronto Public Health reported 850 infections on Wednesday, bringing the city’s total to 50,000 COVID-19 cases since the beginning of the pandemic.

“Our call to action has never been clearer. I cannot urge you strongly enough to keep apart during the holidays,” de Villa said.

“This year, it’s not distance that lies between us, but COVID-19. I know it seems hard to imagine it’s necessary, but many risks are conversing in the holidays this year."

The doctor is urging residents who have committed to following public health advice to speak up, lead by example, and encourage others to do the same.

“COVID-19 can make things much, much worse in Toronto if we make it easy. This holiday, from now into the new year, it is vital that we all find a way to connect but commit to staying apart,” de Villa said.

“The more voices there are taking a stand, the more impact our resolve will have.”

Dr. de Villa joined CP24 to answer questions from viewers about the COVID-19 pandemic.

CP24: Toronto reported a single-day high of 850 new COVID-19 cases on Wednesday, Dec. 16. What is going on? What are we doing wrong here?

De Villa: I think the issue is that there are still people out and about and having social interaction, which actually gives rise to the continued spread of COVID-19. But that being said, this is within our control. This is something that we can absolutely control, and we know what to do. We've done it before in the spring. We were very successful in terms of flattening the curve. I also mentioned that in my remarks, so we actually have the recipe in our hands. It's all about those self-protection behaviours -- wearing your mask, watching your distance, washing your hands.

CP24: It seems like people's behaviour towards the second lockdown is different than what we saw in the spring. It feels like people see this lockdown as more of an inconvenience. Are people not as frightened? What are you seeing?

De Villa: I think that's a very real sentiment and I think what we're seeing are very real human behaviours and reactions to very difficult situations. But I would look at it this way. We know what works and we know that actually staying at home as much as possible, as we did in the spring, and limiting our interactions to the greatest extent possible is part and parcel of what it takes to bring the spread of this virus down. We also know now that this virus actually does spread very easily. We have to be constantly vigilant around what it is that we're doing. But we know it actually works. And now we have vaccines. It is now starting to get administered to people. There's some real light, some real hope available to us. But we also know that the more we are able to control the spread of COVID-19 by our own actions, by adopting those self-protective behaviours as much as possible, we know that we can help that vaccine be the most effective tool available to help us as part and parcel of our COVID-19 response.

CP24: You have the power to enforce stricter lockdown measures, yet you have not done it. Could some kind of regional lockdown come into effect on Friday with the Ontario government?

De Villa: Actually, I had used powers under the Health Protection and Promotion Act when those were warranted. I think you can count on local medical officers of health all around the province to make reasonable assessments around what is happening in their jurisdiction and use their powers but again, very judiciously. Generally, within the realm of public health and within medical practice writ large, it makes the most sense to try to encourage and educate people into the appropriate behaviours rather than using force. If there is a way to avoid the use of heavy measures, like orders or other authorities that are similar to that, then clearly, that's always a better way to go. We also know that with these kinds of measures, it is better if they are done on a regional basis, particularly given that we are so mobile as a population. People go back and forth between Toronto and the regions all around on a pretty regular basis. So, regional measures do generally work better, especially for the kinds of circumstances that we're in right now.

CP24: Do you think we should have been more aggressively testing in schools to get a sense of where things are so that perhaps people would have made maybe different decisions about what they do over the holidays?

De Villa: I think testing is an important part of the COVID-19 response. We've certainly seen the provincial government who is responsible for testing, seek to expand access to testing and to expand the capacity for testing throughout the entire province. I can also say that here in the City of Toronto, we've participated in this provincial initiative to provide for asymptomatic testing within schools, particularly in those high incidence neighbourhoods. The best thing to do right now, from an individual level that's within everybody's control and capacity, is to stay home as much as possible. Don't do Christmas the traditional way this year. Don't do the holidays, whatever holiday you celebrate in December. This is not the time to have those extended family gatherings, not this year. We're asking people to do it differently, so that we can get back to the more traditional kinds of celebrations next year and for all the holidays thereafter.

CP24: A viewer asks, in addition to the restrictions placed by the province, I'm just wondering if the City of Toronto have any additional restrictions at any point over the Christmas holidays or beyond.

De Villa: I think we were talking a little bit about how there is so much mobility here in the Greater Toronto and Hamilton area, that while it is important to think about what can be done to support people in their ability to adopt those self-protection measures that we know that works. It's best if we can do these things, though, on a regional level. I would suggest that let's let those conversations that are ongoing now continue. There's much conversation I know happening. Our political partners are having discussions. Those of us in the public health community are having many discussions around how best to manage the current situation. Do stay tuned. I'm hoping that we'll be able to provide more details to the public around what a concerted approach might look like over the holiday season and beyond.

CP24: Is the COVID-19 app still a significant tool as it's been pitched to be throughout the pandemic? Do you find that it's been effective? Is it working when it comes to contact tracing and identifying people who are in contact with people who have COVID?

De Villa: I don't have specific data on how much the app has been able to help in terms of contact tracing or the next sort of generation of case identification. I'm certainly happy to go and take a look at that and see what we have, specifically at Toronto Public Health. But I will say this, using different tools, whether they're technological or otherwise, to help support contact tracing efforts or case identification efforts, I think are a small thing that each of us can try to do as well over and above staying home as much as possible, and practicing self-protective behaviours. So, certainly, knowing if you're out and about where you were, with whom you were, and you know, for what duration of time is actually really helpful should you be identified either as a case or as a contact of somebody who has COVID-19. I do think that those are helpful things that people can do.

CP24: A viewer asks, is it okay to gather in the garage for Christmas with under 10 family members? Would that be considered outdoors?

De Villa: I really do understand how much people want to get together at this time of year. But the best advice that I can offer everybody is to resist the urge, break with tradition for this one year. This is not the year to maintain those family traditions, particularly if we want to be able to enjoy them safely for many more years to come. This is the year to stay at home and to only celebrate in person with the people that you regularly live with. For everybody else, best to connect with them virtually. I appreciate that people are trying to find safer ways, and the outdoors is generally safer. I will say that. But it is winter, and it's hard to stay outside. So, the best thing to do is to really just keep it to your household for this year the people that you live with. Connect virtually. Do stay connected with friends and family but do so via the phone or any other video conferencing platform, whatever you prefer, but virtually and remote for those who don't live with you.

CP24: A viewer asks, why is the government so hesitant to transition all in-person classes to online learning for the first two weeks after Christmas and New Year's to keep staff and students safe? Is that still possibly on the table?

De Villa: I think to my mind the best thing to do in these circumstances is to keep your options open and to be open to different considerations. I think that the provincial government, school boards and schools and certainly local public health officials have been having discussions about this issue for a number of weeks now and conducting assessments and trying to understand what makes the most sense. I think people need to know, though, that these decisions are actually not as simple as they might seem on the surface. While there are COVID-19 concerns and actions that can be taken to control COVID-19, one has to think of the unintended consequences that might arise as well. What does that mean for people who don't have access to video conferencing tools or tools to support remote or online learning? What about the benefits that are associated with in-person schooling? These are just two of the considerations that need to be reflected on and taken into account as one makes the decision. So, these are the kinds of things that people are talking about, and I expect that those decisions should be landed in the not-too-distant future.

CP24: Peel and Toronto have been in lockdown for four weeks. Why are we still on the rise in COVID-19 when we're under lockdown? Do we have any scientific proof that we did the right thing, closing down restaurants and barbershops and leaving schools open? Would it be wiser to lock down everything for a month and make it mandatory to stay at home, with no exceptions?

De Villa: First and foremost, we know from our own experiences in the spring, from the scientific literature and from the experiences of other jurisdictions, that limiting social interaction really does work with reducing and limiting COVID-19 spread. We also know that what was predicted to happen in jurisdictions like Toronto and Peel. Had nothing been done this fall in respect of restrictions, they were actually predicting that we would be above 1,000 cases a day at this point in time. While we certainly have hit a higher case count today, we have managed to keep the case counts lower than had been anticipated and predicted through models at this point in time.

However, it's clear that we still need to find more opportunities to support people in limiting their interactions with others. Hence, we're continuing to tell people and to remind people of the importance of staying home as much as possible, limiting their interactions with those outside of their home and really focusing only on having close contacts with people with whom you live and when you're out and about wearing your mask as much as possible and washing your hands. These are the steps that we know really do make a difference. And to the extent that the restrictions that were put into place have reduced, we know that they have helped for sure.

CP24: A viewer asks, for those of us who have been working at home for nine months, learning remotely and strictly adhering to all the public health guidelines, what advice do you have for those of us who are extremely discouraged by the current situation?

De Villa: First and foremost, I would say to people like the viewer, thank you. Thank you for following public health advice and guidance. You are absolutely contributing hugely to our fight against COVID-19. I think the one thing I would say to people who are discouraged, having been following all the rules, is to step up and stand up and let people know that this is what you're doing. Let's encourage everybody else to join in following this good advice and guidance so that we can actually put COVID-19 behind us all and to help the vaccines do the work that they need to do. So that would be my advice to those who are feeling discouraged. Let's get others on board.

CP24: There's a motion at Toronto City Council wanting to deem Santa Claus as an essential service. The debate has been raging around the potential mixed message here about bringing someone at home ever so brief as Santa would be but also be having people perhaps having to go out to make sure the stockings are stuffed and there are gifts under the tree here. What do you make of this idea of Santa as essential?

De Villa: I try not to get involved in political debates. But I will say this; I think we could all use a little bit of Christmas cheer. My sense is that Santa has got some pretty special powers, and he'll manage to figure his way around how to make sure that everybody gets that Christmas cheer. I would just remind Santa that even though he is Santa, he's still expected to follow the measures for self-protection. I'd asked him to watch his distance, wear his mask and wash his hands.

This interview has been edited.