The arrival of COVID vaccines have stirred excitement and optimism for a swift end to the global pandemic, with some seeing the shot as a 91裸聊视频渇ree pass91裸聊视频� to soon gather and socialize as they did pre-2020.

Not so fast, experts say.

Canada91裸聊视频檚 first phase of vaccine rollout 91裸聊视频� targeting front-line health-care workers, long-term care residents and staff, and some Indigenous populations 91裸聊视频� began last month and is expected to stretch into March before the inoculation process is opened to a broader population this spring.

While experts agree the end of the pandemic is in sight, they say it will take time to determine what level of protection the new vaccines actually provide 91裸聊视频� and whether they prevent us from spreading the virus.

Experts expect mask mandates, limits on gatherings, and physical distancing measures to continue even as more of us get vaccinated, at least through part of 2021.

91裸聊视频淯ntil we get to a level of herd immunity where we have around 70 per cent of our population vaccinated worldwide, there91裸聊视频檚 going to be that question of transmission,91裸聊视频� said Jason Kindrachuk, a virologist with the University of Manitoba. 91裸聊视频淎nd that91裸聊视频檚 certainly a concern for us.91裸聊视频�

Both Pfizer-BioNTech and Moderna, the two vaccines currently approved for use in Canada, were shown in clinical trials to have a 95 per cent efficacy in preventing severe infection from the virus that causes COVID-19. And while Moderna has some evidence suggesting it also decreases transmission, more data is needed.

Some vaccines, like the one for HPV, offer complete protection from infection and transmission, while others like the flu shot primarily work against acquiring the virus and lessening the severity of symptoms. Kindrachuk says part of the reason for that is the way our immune systems respond to different vaccines.

The COVID vaccine seems to effectively produce neutralizing antibodies, he says, 91裸聊视频渂ut not necessarily enough to stop the virus from potentially getting into some of our cells.91裸聊视频�

Dr. Sumon Chakrabarti, an infectious disease physician in Mississauga, Ont., says answers to the transmission question will only come as 91裸聊视频渓arge swathes of the population91裸聊视频� start getting vaccinated worldwide.

We may see that the inoculations do decrease transmission, he says, and restrictions could be lifted earlier than experts expect.

91裸聊视频淏ut as it stands in January 2021, when you get vaccinated you91裸聊视频檒l want to still act like you were doing before: physical distancing, keeping contacts low, masking indoors,91裸聊视频� Chakrabarti said. 91裸聊视频淎s the pandemic starts to ease up, things will change.91裸聊视频�

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Being able to still transmit the virus becomes less of a problem as more and more people are vaccinated, experts say.

But Horacio Bach, an adjunct professor of infectious diseases at UBC, doesn91裸聊视频檛 expect SARS-CoV-2 to ever be eradicated.

If 30 per cent of the population isn91裸聊视频檛 immunized, the virus will continue to circulate through them, he says. So effective treatment for COVID-19 will be needed to deal with lingering cases.

91裸聊视频淰iruses don91裸聊视频檛 have brains but they91裸聊视频檙e not stupid,91裸聊视频� he said. 91裸聊视频淭hey will continue to find hosts.91裸聊视频�

Dr. Isaac Bogoch, an infectious disease expert with the University of Toronto, says COVID-1991裸聊视频檚 potential staying power will have less of an impact once pressure is relieved on the health-care system. And that will be achieved by vaccinating high-risk populations early in the rollout.

The first indication that vaccines are working will be a reduction in deaths as long-term care and other high-risk groups are immunized, he says, while case counts will be the last to decrease. That means infection prevention controls will need to be followed while community transmission is still happening.

91裸聊视频淓ventually you91裸聊视频檒l start to see a reduction in cases as these vaccine programs roll up, and then we91裸聊视频檒l start to see public health measures slowly lifted as the year progresses, post-April,91裸聊视频� he said. 91裸聊视频淲e91裸聊视频檒l probably see a gradual shift allowing larger outdoor gatherings, then indoor gatherings, and eventually lifting of mask mandates.91裸聊视频�

An exact timeline for reaching that level is hard to predict, however.

While a highly effective vaccine will allow us to reach herd immunity quicker, Bogoch says a 95 per cent efficacy in a clinical trial might not actually translate that successfully in the real world.

Since efficacy was based on a two-dose regime, Bogoch expects that number to drop if people don91裸聊视频檛 return for a second shot. It91裸聊视频檚 also still unknown how effective the vaccine is for segments of the population excluded from clinical trials.

So visiting a grandparent or other high-risk individual in the next couple months will be risky, Bogoch says, even if they91裸聊视频檝e been vaccinated.

91裸聊视频淭he effectiveness is probably going to be lower (than the trials showed),91裸聊视频� he said. 91裸聊视频淎nd we91裸聊视频檒l need to see how this plays out in real time to help drive our behaviours.91裸聊视频�

This report by The Canadian Press was first published Jan. 8, 2020.

Melissa Couto Zuber, The Canadian Press