With the Omicron variant of COVID-19 spreading across Ontario, many questions are arising about how to protect yourself as we head into the next wave.

Phil Perkins spoke with Infectious Disease expert Dr. Dominik Mertz to learn what steps we can take to protect ourselves from infection, who is most at risk and get a better understanding of the benefits of a booster.

COVID-19 Q & A with Infectious Disease Expert

Phil (P): What do vaccines do against Omicron? Are two doses enough anymore?

Dr. Dominik Mertz (M): First and foremost, it reduces the risk for the person who is vaccinated from getting severe disease or potentially die from COVID-19. That’s what the vaccines are best at and always have been. And with Omicron, even more so.

Where the vaccines give a significant hit is for the neutralizing immunity. [It helps] your ability to prevent from getting infected to start with and, as such, to prevent infecting someone else.

With two doses, the risk [of getting COVID-19] has increased again because Omicron can escape some of that immunity. With the third dose, we can improve that again. How high we get or will it be as effective as the two doses for Delta, still needs to be seen. But based on most of the data we have seen, it looks like it restores most of that hit by getting that third dose.

There is a benefit with a third dose in restoring that neutralizing immunity to a relatively large extent.

P: What about transmission? People were initially being told they aren’t just getting the vaccine to protect themselves but to also protect others.

M: If it can prevent you from getting infected, it reduces the risk for everyone around you as well. That’s the first way vaccines can help prevent transmission by making sure you don’t even get the infection. The data around if you are infected, to what extent can you infect others, has been very mixed.

P: Who is being admitted to hospital and the intensive care unit (ICU)? Are we seeing healthy individuals or mostly those with pre-existing conditions?

M: The main risk factor that we have for hospital admission and ICU admission is, first and foremost, lack of immunity. If you’ve had no vaccine and no former infection [of COVID-19] then that puts you into a much higher risk category. Among those, it’s particularly those who are elderly, who are frail, who have multiple comorbidities. It puts you at a higher risk of requiring that care.

We clearly saw that age is also a main risk factor that people have. There is nothing you can do about that – you are either 80 or you’re 40.

Take two patients in the same age group, one entirely healthy and the other with multiple comorbidities like obesity or diabetes, the second person’s risk would be significantly higher risk than the first.

P: How many children have been admitted to hospital due to *just* COVID-19?

M: In Hamilton, we’ve had 91 discharges of children who had a diagnosis of COVID-19 since the beginning of the pandemic up to October. But this [data] doesn’t give you information on whether these were coincidental positive cases or admissions to hospital because of COVID-19. It’s a mixed bag, that’s for sure. We see both.

We probably picked up more coincidental cases than in adults because [kids] tend to be less symptomatic or the symptoms may be less clear. So we very much err on the side of caution in testing them and they may have come in for another reason.

P: How effective are masks that are not N95?

M: It’s hard to pinpoint a specific percentage for risk reduction. Well-fitted medical masks are probably better than just a cloth mask. Any type of face covering has some level of effect but nothing is perfect.

Some recent data shows a mask can have 45 to 50 per cent risk reduction.

Even a relatively small difference in risk reduction can make a difference for the population at large. That’s one piece to keep in mind if you feel like 40 to 50 per cent risk reduction seems quite low. For the individual, it’s not great. But at the population level, it still makes a difference and that’s talking about an indoor prolonged exposure kind of scenario.