The world marked the one-year anniversary of the World Health Organization declaring the COVID-19 crisis a pandemic on Thursday.

Since then, more than 101,000 Torontonians have been infected with the disease, and over 2,700 people have died in the city because of the virus.

Dr. Eileen de Villa, Toronto’s medical officer of health, joined CP24 to answer COVID-19-related questions.

CP24: We have several viewer questions about the AstraZeneca vaccine. One viewer asks why it is being administered to those between the ages of 60 and 64 instead of younger age groups? Another viewer wants to know your opinion on some countries suspending the vaccine because of patients getting blood clots. Should I still get the vaccine?

De Villa: There's a lot to go through there. Many questions and I appreciate that this is a subject of great interest to so many people. First and foremost, you may recall that earlier this week, I talked about vaccines, and frankly, the best vaccine is the one that's in your arm. That's how a vaccine is effective. So, one of the things that I've spoken about is that we're fortunate right now that we have a number of vaccine products that are licensed for use in Canada. And they are all effective at preventing the most serious outcomes associated with COVID-19 infection, whether we're talking about serious illness leading to hospitalization or serious illness leading to death. All the vaccines that have been approved for use in Canada, including AstraZeneca, have been shown to be very effective at doing that. These are the important outcomes that we are most worried about and the kinds of outcomes that we're seeking to prevent. And so, the vaccine can only be effective once you've actually received it. And my advice to people is that one, for starters, I would be happy receiving any one of the vaccines that's available in Canada, and the most effective vaccine for people to get right now is the one that they're actually able to get in their arm. I would strongly recommend the vaccines.

Now I know that there's been some new news today in respect of what's happening in Europe and in Denmark and Norway, in particular, we've heard about a suspension of vaccine programs there. Certainly, one should pay attention to what's happening. I know that health authorities here are connecting with the health authorities in Denmark and Norway to find out what's happening so that we can understand whether there's any impact on our program here. But in the first instance, from what I can understand, based on the reports I've seen so far, is that this is a precautionary measure that they're taking at this point in time. We can continue to watch and see what happens here in Canada. But again, this product is licensed, and I would tell you this -- millions of doses of this vaccine have been provided to patients all around the world. This is a new report that we're hearing. The suspension is precautionary. And thus far, what we're seeing, particularly in the United Kingdom, is that infection rates are going down with this vaccine. This AstraZeneca vaccine, in particular, has been used by millions of people.

READ MORE: No sign Oxford-AstraZeneca vaccine causes blood clots: Canadian health authorities

CP24: A viewer says she and her husband are 62 years old and are having a difficult time whether to get the AstraZeneca vaccine. We've read reports that it is not effective against the South African variant, which is increasing in Ontario.

De Villa: Again, the most effective vaccine is the one that you're actually able to get. If there is an opportunity to get this vaccine, and it sounds like for this individual that there is an opportunity and that they're eligible to receive it now, I would recommend getting the vaccine. That's why it's there, and it's available. You can't get the benefit of the vaccine without actually using it. Again, I would remind people that COVID vaccines are being used all over the world and yes, that includes the AstraZeneca vaccine. I do think it's appropriate for other authorities around the world to suspend their programs as a precautionary measure. But right now, we have good reason to believe that this is an effective vaccine. It's been used with millions of people around the world. And I would recommend that anyone who has the opportunity to get any one of the vaccines that's licensed for use in Canada now should take that opportunity as one of the best ways in which they can protect themselves against serious outcomes associated with COVID-19.

CP24: A viewer says she is in Etobicoke and spent most of the day calling the closes Shopper's Drug Mart on the list. She says she got a recording that they don't have the vaccine. She got the same response when she called Rexall. North Etobicoke is one of the hardest-hit areas by COVID-19, and yet vaccines are not widely available.

De Villa: I think it's really good news that people are interested in getting the vaccine and are listening and seeing that, yes, this vaccine is effective. We've seen the benefits of vaccines within our long-term care homes and our retirement homes. Infection rates and any kind of serious illness have really dropped off in those settings now that they're actually vaccinated. And that's the exact benefit that we want for everybody in our city as soon as possible.

It's now a question of getting adequate supplies and having enough to get to as many people as possible. That's not possible right now because of supply. As people know, we've had some supply challenges over the past several weeks now. As vaccine supply gets more stable and as the number of vaccines available to us grows, we will be able to get to more and more people. The pharmacy initiative is relatively due it's just the beginning. I would encourage people to continue if you fit within those eligibility criteria, please do go and try and get the vaccine. If you don't get it now, don't worry, opportunities are yet to come. And we are trying to get out vaccine as quickly as possible. Certainly, in Toronto, when we get big supplies in, we're opening mass immunization clinics next week for 80 and over, and we're looking forward to getting out to more and more people as soon as supply allows us to do that.

READ MORE: Here's who is eligible for a COVID-19 vaccine shot at Ontario pharmacies

CP24: We've heard about a situation in York Region where all residents of a retirement home have been vaccinated. However, an outbreak has been declared at the home, which could be linked to some caregivers who do not want to be vaccinated. There is vaccine hesitancy. When looking at long-term care homes in Toronto or retirement homes, is there anything being done within the city to have those caregivers avoid going into those homes if they're not being vaccinated?

De Villa: I think the more significant work that's happening now is actually trying to address vaccine hesitancy. And I think one of the most compelling things to reduce vaccine hesitancy is that when they see their fellow healthcare workers getting vaccinated and actually being successfully protected against COVID-19. That's perhaps one of the most compelling pieces of evidence. It's real life, it's people that you can see. What we've found here in Toronto, as people are witnessing firsthand the benefits of the COVID-19 vaccine and the protection that it affords, is that people are increasingly asking for the vaccine. They might have taken a pass on it at the beginning, but now they're actually saying, hey, you know what, this might actually be worth my time in trouble now because I can see that it actually is beneficial, and I don't see people being harmed by the vaccine. That's a really good news story that we're seeing the protective benefits for residents and for those staff who choose to get the vaccine. And that real world evidence is actually compelling people to rethink decisions to not take the vaccine before.

CP24: The province released the latest COVID-19 modelling, and the next three weeks will be critical in our fight against the disease and the variants. What is your take right now on the status of the variants in Toronto? How concerned are you?

De Villa: I am, of course, concerned. I'm sure that Dr. Williams that Dr. Brown explained the concern that we have around variants of concern. We know that these variants. The B.1.1.7 variant, which is most prevalent here, also known as the U.K. variant, is more transmissible than the previous variants of COVID-19 that were circulating here. And as well, it has been increasingly associated with more severe illness. These are exactly the kinds of outcomes we're seeking to prevent and stop from happening here. And we know what works actually against these variants, distance and all those good self-protection measures actually make a difference. The lower we can bring the levels of disease, the more we can stay vigilant with those self-protection measures -- I know people are tired of them, but they do work -- the more we're able to continue practicing them, the more we're able to reduce the spread of COVID-19 and the better the effect we'll see with our vaccines. We know the vaccines work. We need to give them the best chance at working by keeping disease levels low.

READ MORE: COVID-19 case declines have 'stalled;' Ontario model says 6,000 cases a day possible by April

CP24: Mississauga wants to move to the red zone. How do you feel about that? Would you be looking for Toronto to go into the red zone anytime soon? What would it take for us to get there?

De Villa: This is one of those issues that has to be approached with extreme caution. And I think that that was one of the key messages that Dr. Williams and Dr. Brown were trying to get out today. Our behaviour in the next few weeks is absolutely critical. To the extent that we can moderate our behaviours, that we're limiting our interaction with others in really practicing those self-protection measures through distancing and masking and hand washing -- that's what we'll see us through and give us the best chance that having vaccines do their best work for us and give us the best chance at actually getting back all those elements of life that we've been missing so much for the last year. What we've seen in the evidence, what we've seen from other jurisdictions, is that reopening and restoring activity is something that's best done slowly and cautiously if we are to keep disease levels down, get the best impact of vaccine and actually the best chance at restoring you know life more likely knew it before.0--

CP24: A viewer says he is a transplant recipient kidney in 2016 and also an essential worker in the transportation sector. For the past two months, he says he's been trying to find information on when people living with transplants will get their vaccine.

De Villa: if I remember our provincial prioritization framework properly, I believe that Nick, regardless of how he's felt, would probably fit into phase two. I believe that that should really be starting around April, again, depending on how vaccine supply goes and how quickly the various local public health units around the province are able to get through all the phase one populations. That's how it stands now. Again, all the vaccines are being done premised on the prioritization framework set out by the province.

CP24: Another viewer says they got their first dose in February. They were supposed to get the second dose later this month, but it was moved to June. They want to know if the first dose will still be effective by the time they get the second dose. They are concerned that the interval between doses is not practical.

De Villa: This is a relatively new development. When the vaccine first came onto the market in Canada, there was a different time frame between the first dose and the second dose. However, with more studies happening and more administration of vaccines over time, the understanding is that that first dose provides very good protection. And we have that opportunity to extend and expand our coverage across the population by expanding the time between that first dose and that second dose. This was reviewed by the National Advisory Committee on Immunization. They've indicated that in Canada, we can create spacing between that first dose and second dose of vaccine by as much as four months. In this way, we can provide greater coverage of the first dose to a larger number of people and create better community coverage by having more people vaccinated with that first dose. As supply becomes available, and as we've got more and more people covered with that first dose, we can still get to those second doses and make sure that everybody has that full some protection from a two-dose vaccine. But we are also creating protection by having a greater number of people covered with that first dose. We're able to get that higher level of protection faster for the whole community.

READ MORE: Vaccine panel recommends going up to 4 months between COVID vaccine doses

CP24: Is there a plan to come to TCHC buildings and vaccinate senior residents instead of asking them to travel to a vaccination site?

De Villa: The short answer to that question is yes. It all depends on the building. And there's a lot of conversation that's happening amongst the vaccine administrators here in the city. There are a number of health sector partners who are participating in giving the vaccine to populations all around the city. And in certain buildings, that will be an option. But there will be many options for people to pursue. The issue is whichever one is the best for you, and your circumstances are the one to take.--

CP24: A personal support worker working part-time at a city-run nursing home wants to know when will they be allowed to work in more than one facility?

De Villa: I'm sorry to hear that this is a challenge. To be honest with you, I'm not really sure when that's going to change. And we can understand that these things have to be approached with some caution, given how we know COVID-19 spread through long-term care homes. I wish I had a better answer for you. But I will wish that viewer the best of luck on the go forward.

CP24: A viewer asks why her mother, who is 93 years old, has not been contacted to get her vaccine?

De Villa: It depends on what the circumstances are. Certainly, for some who have already pre-arranged or have relationships with home care or have a close relationship with a hospital or a particular care provider, a number of care providers have been out there connecting with their patients, trying to make sure that they have the opportunity to sign up and get a vaccine through the channel that makes the most sense for them. If that hasn't already happened, in this case, there are several different places that this individual can go. And again, it depends on what the circumstances are. We know we've got massive immunization clinics coming up next week here in Toronto, and our hospital partners as well have a number of different venues through which people can receive vaccines. So, whether it's through vaccineto.ca or city clinics, those are good places to start that search in this case.

CP24: Another viewer wants to know why churches in Toronto are only allowed to open with 10 people. He says a big church that can normally 1,000 people should be permitted to have a 30 per cent capacity with social distancing in place. Why are malls allowed to open with 25 per cent capacity and not churches? There were hardly any churches in the GTA that had outbreaks before the lockdown.

De Villa: The short version on this one is it, in fact, there were a number of cases clusters and outbreaks associated with places of worship, whether we were talking about churches, mosques, synagogues or any form of places of worship. And part of the challenges is that these are places that are often attended by older members of our community who are particularly susceptible to COVID. And on top of it, it is an environment that promotes socializing, which is exactly what you don't want at this point or when you're dealing with a disease like COVID-19. That's why the restrictions around places of worship and the numbers because of those particular circumstances. Of course, the more we can push disease down and the more we're able to get the vaccine out, hopefully, the sooner we'll be able to get back to enjoying all the aspects of life more like we used to, and that includes being able to attend various places of worship and the ceremonies that are held there.

CP24: "I'm just kind of wondering when the world is going to get back to normal now that the vaccines rolled out. We're slowly reopening. I think people could really use a little light at the end of the tunnel. I'm just curious."

De Villa: I think more than just a few of us are curious about this and there isn't a simple answer to this one. There's definitely light at the end of the tunnel. We know those vaccines are effective, and we know what it takes to reduce the spread of COVID-19. I think the short answer here is this -- the more we're able to follow those self-protection measures for now, and the sooner we're able to take up vaccine when our turn becomes available for each of us, I would just take up that vaccine.