Toronto's top public health official says the city's COVID-19 situation has improved but urged residents to remain cautious as the coronavirus will remain a threat.

Dr. Eileen de Villa, the city's medical officer of health, said at a news conference that case counts in the last few days show that it is stabilizing.

"I liken it to a patient being recategorized from critical to serious condition. It's a better condition, but it's still a long way from best," she said.

"And that is where we are as very early signs of improvement seem to be emerging."

De Villa reiterated that all vaccines are safe amid two new deaths in Canada associated with the rare blood clot condition linked to the AstraZeneca vaccine.

She said the odds of getting COVID-19 without receiving the vaccine are far greater than the risk of a serious complication due to immunization.

"There is a huge drive in medical and scientific communities to produce further understanding of the virus and the vaccine. We now have more than a year of evidence to show what COVID-19 can do," de Villa said.

"What we know today is that the vaccines work. We know that they are the very best protection against COVID-19."

Dr. de Villa joined CP24 Wednesday afternoon to answer questions about COVID-19 vaccines.

CP24: Peel Region announced today that they are opening vaccine bookings to all adults starting May 6. When will Toronto be able to do the same?

De Villa: I have just heard about that in Peel. And I would say that their epidemiology is a little bit different, as I understand it. And again, it's probably better to speak to Peel about this. But I understand that most of the jurisdiction actually does qualify as a hot spot under the provincial criteria. So, in Toronto, we have many postal code areas that qualify as hot spots. And 18-year-olds are eligible from those areas to book for a vaccine. And as we're hearing from our provincial counterparts, more vaccines should be available in weeks to come, and we're really looking forward to putting vaccines in people's arms as that supply starts to grow.

In fact, the province had put out this very specific messaging. They're expecting that sometime by the week of May 24 that vaccine eligibility will be for all those 18 plus. And now we have some new news from Health Canada around expanding availability or the use of vaccines to younger populations as well.

CP24: Speaking of the news from Health Canada, the province said it is working with the Ministry of Education to plan the rollout of the vaccines to kids and teens between the ages of 12 and 15. What do you think the chances are that a good portion of kids in that age bracket or at least high school-aged kids will have the vaccine before heading back in the fall?

De Villa: Everybody wants to see a vaccine in arms as quickly as possible. And now that vaccine is approved for youth, we're interested in seeing young people around the province get access to the vaccine. As with everything, it always comes down to supply. As long as there's supply a vaccine available, I can tell you that the vaccine partners here in Toronto are eager and willing and able to put vaccines in arms. It is just a question of supply. And we'll figure out the way to make sure that we'll put those needles into arms.

CP24: Does the health unit have any plan for targeted messaging for that age group? Vaccine hesitancy is still a thing, even though we see thousands of people getting the shot on a daily basis. There are lineups outside of these clinics. How are you going to target the parents of kids of this age and encourage them to get the shot and that it's safe to do so?

De Villa: I think given that this announcement just came out today, there's still lots of planning that needs to be done. But we are using every communication channel available to us. We have a number of community partners that are helping us in our vaccination efforts currently with adults. And I suspect that those partners will be continued to be really important ambassadors, if you will, for the vaccine, including for vaccination of youth all around the city, particularly in those areas where we need to build more vaccine confidence. That's been successful to date. And my sincere hope is that that will continue to be a part of our success in the future.

CP24: A viewer who got her Pfizer jab two weeks ago wants to know her protection rate. She also wants to know if she can do anything differently now that she has her first dose.

De Villa: I think one of the things you can do differently is to actually comfort yourself in the thought that you're well on your way to protection. But having one dose of a two-dose vaccine still means that you're partially vaccinated. The complete course of vaccine for Pfizer means that you need that second dose. So, in the meantime, we're encouraging people to continue to practice those measures for self-protection. You need to continue to maintain your distance or wear a mask. Outdoor activities are certainly safer than the ones that are indoors. There is still a risk. It's not big, but there is still a risk, and we would encourage people, for now, to continue to practice those measures for self-protection. And as more and more of us get a second dose on board, we can start to think about how we might do things differently. That's what we're seeing in other jurisdictions. I think we can expect to see something quite similar here.

CP24: The viewer also wants to know about getting the second dose of the Pfizer vaccine sooner as supply will increase in the coming weeks.

De Villa: As more supply becomes available, that may be a possibility. It all is very much dependent on supply. Right now, we're focusing on making sure that we can get as many people as possible that first dose so that they can start to get that protection in their system. And then, as supply becomes available, we're looking forward to providing more and more of those second doses. And again, it is all about supply.

CP24: A viewer who has her first dose of the AstraZeneca vaccine asks who will be providing the date for her second dose as the pharmacy has not confirmed it yet. Also, she wants to know if the second dose will be Pfizer, given the lack of supply of the AstraZeneca shot.

De Villa: That is a difficult question to answer right now. I don't know that any of us have an answer at this moment in time. I would suggest to anyone who finds themselves in this situation to definitely stay in touch with the pharmacy. I think they'll probably be the best route of information, having been the provider of that first dose. I'm not sure what's happening with respect to supply. But I know that there are lots of questions and there's certainly some research that's being done and some formal consultation happening between our provincial counterparts and our federal counterparts, particularly those who give advice on how to use vaccine around what should be done. Is there the possibility to mix and match vaccines, especially if supplies an issue? Those questions are actually being studied right now. The early indications would say that look if you use one vaccine for dose one and another for dose two because of a supply challenge that shouldn't be harmful. But we still have some questions about how much protection does that provide you. How much benefit does that provide you? I would ask that people stay tuned as we try to figure out some of those sticky questions.

CP24: A viewer asks, how many patients, we're not sure if you know, in Toronto ICUs have received one dose of a vaccine?

De Villa: I do not know off the top of my head. But what I will do is I will undertake to find out that information. I don't have the information right in front of me, but I understand that my colleagues at Public Health Ontario have actually looked into this. And the number and the rate are actually quite low. I just don't have the number at my fingertips. While we do talk about one dose being partially vaccinated, it's not a complete course of vaccination yet, and I would say this, the evidence is quite encouraging, that you are getting some protection. We're still encouraging that people follow those self-protection measures, but that people should have confidence that vaccine is offering the kind of protection that we're looking for, for all of us to help get us to the other side of this pandemic.

CP24: A viewer wants to know if those turning 18 this year can book a vaccine appointment. She says she lives in a Durham hot spot and booked an appointment for her 17-year-old son, but it was cancelled.

De Villa: I'm sorry to hear that. I can't speak specifically to what is happening in Durham, but I would say this. My understanding is that with the provincial booking system that when they're looking at 18+, that's done by birth year. For this year, that would be anyone born in 2003, not the exact birth date. That's my current understanding of the system.

CP24: Another viewer asks when you think those 16 years old may be eligible for vaccination?

De Villa: My understanding is that many conversations are happening right now around how we can take advantage of Health Canada's latest foray and expansion of vaccine eligibility to a younger population. At this point, I don't have specific details on that. I do know that the province is working on this with various healthcare partners, and we should hope to have information to share with the public soon. Do stay tuned. Glad to hear that people are interested in having young people in their families get vaccinated against COVID.

CP24: A viewer asks if someone living with HIV considered one of the high-risk groups? If you received the first dose of the Pfizer vaccine and have HIV, should you get your second dose within 21 to 28 days? Or wait for 16 weeks like everyone else? If you need to get the second dose within 21 to 28 days, how can you do that at a pop-up clinic if that's where you received your first dose?

De Villa: Those with certain conditions that actually make their immune systems less robust in terms of functioning are eligible to get the vaccine on the shorter interval between that first and second dose. And as I understand it, those who are eligible for this should be contacted by their physicians, and if they have questions about this should be contacting their physicians if they haven't heard. Through that contact with the healthcare system, processes can be found to get you that vaccine sooner. For example, certain cancer patients are eligible to get their vaccine at an earlier point in time for that second dose rather than wait for the full time. That's something that your health care providers should manage. As far as I understand it, they should be contacting those patients to help them connect to get that second dose in the earlier timeframe.

CP24: A viewer says she is pregnant and has received her first vaccine dose. She wants to know if her husband is eligible for a shot. If so, she wants to know how he would demonstrate his eligibility at his appointment.

De Villa: I'm glad to hear that you've received that first vaccine and congratulations on the pregnancy. When it comes to your husband, the question is, does he currently fit one of the eligibility criteria. This may depend on his age, where you live, whether he has a certain medical condition, whether he works in a particular area. As of tomorrow, there are a number of essential workers that are eligible – teachers amongst some childcare providers, etc. For a full list of who is eligible, I would strongly recommend that you visit our website, toronto.ca/COVID-19. These are the people who are eligible to receive the vaccine. It's all really well listed out on a chart. And I would, of course, encourage that he gets that vaccine as well as soon as his turn comes up and as soon as he's eligible.

CP24: Is he not eligible based on his caregiver status?

De Villa: There is eligibility for what's considered an essential caregiver, including essential caregivers to pregnant women. However, the caregiver relationship in question is one where that caregiver actually has to support the pregnant woman in terms of activities of daily living -- feeding, dressing, that kind of thing. Very active and involved caregiver support. Otherwise, the other eligibility criteria would be the ones that would apply.

CP24: A viewer wants to know if her 56-year-old mother-in-law, who is visiting the country, can get the COVID-19 vaccine.

De Villa: It is possible for people who are non-residents of the province to receive the vaccine. My strong suggestion would be to either connect with us at Toronto Public Health, and the phone number for that is 416-338-7600. The folks on the phone can help guide you to the best way to get access to vaccines for a visitor who would be somebody who would not have OHIP. We'd like to make sure that people in our community are getting appropriately protected against COVID-19 to minimize the risk to all of us here.

CP24: A viewer on a waitlist for a vaccine at a Toronto pharmacy asks, are there any talks of bringing Pfizer or Moderna or even J&J to those pharmacies since we can't depend on AstraZeneca? She says she feels like they've been forgotten.

De Villa: Not forgotten. I can certainly guarantee that. And there are a number of initiatives that my provincial counterparts have now taken on. There are some pilots happening in pharmacies, some of which were just announced earlier today by the province around using Moderna within pharmacies. As well, there are some Pfizer pilots that are underway so that we can test out how these vaccines can be used successfully within a pharmacy setting. And the hope, as I understand it, is that the province will scale up those initiatives once they've had the opportunity to really test them out. You want to make sure that you've got everything worked out - all the little details - before really ramping up to a broader range of pharmacies around the province. Stay tuned for now. And keep your fingers crossed that all goes well so that we can see more of that product available through the channels like pharmacies.

CP24: A viewer says COVID-19 has also affected zoo animals and pets. He is wondering when do you think animals can get vaccinated?

De Villa: That's a very interesting question. And I have to tell you, veterinary medicine is not my area of expertise. Why don't I ask my colleagues at the Toronto Zoo what they know about this? They're probably far better positioned to answer that question. Interestingly, it's not entirely certain that we know which animals can be affected by COVID and what that means. We've certainly seen things with cats and with minks. I admit I don't know the full range of animals that can be affected by COVID. But I'll endeavour to find out from people who know more about animal medicine than me.

CP24: A viewer wants to know if it's okay to give a ride to a co-worker and, for safety, keep the mask on.

De Villa: I can tell you this that what we have found in our investigations of clusters or outbreaks of COVID-19, particularly related to workplaces, one of the key factors in the transmission is things like carpooling because you're in a closed space with other people, oftentimes without a mask. Just a reminder to people that the kinds of activities that give rise to COVID risk -- enclosed or indoor space without a lot of distance between people and without masks. We're currently advising as much as possible if you can avoid carpooling. That's the best thing to do. If you find yourself in a circumstance where you have to be in a car with other people with whom you don't live, the best thing to do is try and keep your distance as best you can in the car and to open the window to try to account for greater ventilation to minimize the risk. And wearing a mask would be an important self-protective behaviour in that circumstance. But if it can be avoided, that's the best thing to do when trying to reduce the spread of COVID-19.

CP24: Final thoughts? What are you looking ahead for the next week?

De Villa: To continuing to deliver vaccines to as many eligible people as possible. And in the meantime, I would just encourage people to really stick to the stay-at-home order. It is so important. I can't stress enough how important those self-protection behaviours are at this point in time -- keeping distance as much as possible, staying home as much as possible, only going out when you have to and when you're out and about again, keeping distance if you can't wear your mask. You know all the good behaviours that we need to continue to practice. That's what we'll see us through.