The COVID-19 pandemic

[panamaniac]

So, which local projects are now on hold due to today's announcement?

[KingandWeber]

So, which local projects are now on hold due to today's announcement?

Well it would seem most of the condos can technically continue as "Residential construction projects where ... an above grade structural permit has been granted for condominiums, mixed use and other buildings" are exempt unless above grade structural permit doesn't mean what I think it does (which is quite possible!)

[MidTowner]

I'm assuming they mean a two year recovery period and not a two year shutdown.  Governments will be under huge pressure to begin restarting the economy in about two to three months time, or as soon as there is some level of assurance that health care will not collapse, whichever comes sooner.  I could see senior citizens remaining in self-isolation until the fall, or longer, if the virus persists through the summer.  What happens next "season" is anybody's guess at this point.

Edit:  I see that they meant up to two years with covid-19 in circulation.  One hopes not, but it was already known that that was a possibllity.

Doesn't it remain in circulation until some critical proportion of the population achieves immunity, either through having contracted it or having been administered a vaccine? And the more we slow the spread, the longer the former takes. And since a vaccine is twelve or eighteen months or more away, two years seems reasonable, or even ambitious.

[taylortbb]

Unfortunately it's only in vivo.

I think you mean in vitro.

You are correct, edited my post.

[danbrotherston]

I'm assuming they mean a two year recovery period and not a two year shutdown.  Governments will be under huge pressure to begin restarting the economy in about two to three months time, or as soon as there is some level of assurance that health care will not collapse, whichever comes sooner.  I could see senior citizens remaining in self-isolation until the fall, or longer, if the virus persists through the summer.  What happens next "season" is anybody's guess at this point.

Edit:  I see that they meant up to two years with covid-19 in circulation.  One hopes not, but it was already known that that was a possibllity.

Doesn't it remain in circulation until some critical proportion of the population achieves immunity, either through having contracted it or having been administered a vaccine? And the more we slow the spread, the longer the former takes. And since a vaccine is twelve or eighteen months or more away, two years seems reasonable, or even ambitious.

The answer to the first part of your question is, no, it doesn't have to remain in circulation.

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

If you can do this in a local area then you can shrink the infected population then reduce restrictions while controlling new cases through tracing, testing, travel restrictions, and quarantining, you can be free of a virus, even without herd immunity. In theory at least--I think we're yet to see if this is possible in practice with this virus but the short answer is no, it's not necessarily the case that everyone must get the virus before herd immunity is acquired.

It's also not necessarily the case that "everyone getting it" would actually provide protection either, this virus does mutate, and while I think experts haven't seen it mutate sufficiently to avoid new immunity (nor do experts even know how long or effective acquired immunity is for this virus), it's entirely possible that it could mutate in that way in the future, just as the flu and cold viruses do every year. In fact, again, I'm not an expert, but I believe that everyone getting it, would make it more likely that it would mutate in that way.

I am curious though, why you believe that a vaccine that is available in 18 months would take 2 years to give us herd immunity? I believe the 12-18 month estimate is for broad availability of the vaccine--and we're already 2 months into that timeline.

[panamaniac]

Doesn't it remain in circulation until some critical proportion of the population achieves immunity, either through having contracted it or having been administered a vaccine? And the more we slow the spread, the longer the former takes. And since a vaccine is twelve or eighteen months or more away, two years seems reasonable, or even ambitious.

The answer to the first part of your question is, no, it doesn't have to remain in circulation.

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

If you can do this in a local area then you can shrink the infected population then reduce restrictions while controlling new cases through tracing, testing, travel restrictions, and quarantining, you can be free of a virus, even without herd immunity. In theory at least--I think we're yet to see if this is possible in practice with this virus but the short answer is no, it's not necessarily the case that everyone must get the virus before herd immunity is acquired.

It's also not necessarily the case that "everyone getting it" would actually provide protection either, this virus does mutate, and while I think experts haven't seen it mutate sufficiently to avoid new immunity (nor do experts even know how long or effective acquired immunity is for this virus), it's entirely possible that it could mutate in that way in the future, just as the flu and cold viruses do every year. In fact, again, I'm not an expert, but I believe that everyone getting it, would make it more likely that it would mutate in that way.

I am curious though, why you believe that a vaccine that is available in 18 months would take 2 years to give us herd immunity? I believe the 12-18 month estimate is for broad availability of the vaccine--and we're already 2 months into that timeline.

Don't most vaccines take about two weeks to generate immunity?  I guess longer if it's something that requires a booster.

[danbrotherston]

The answer to the first part of your question is, no, it doesn't have to remain in circulation.

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

If you can do this in a local area then you can shrink the infected population then reduce restrictions while controlling new cases through tracing, testing, travel restrictions, and quarantining, you can be free of a virus, even without herd immunity. In theory at least--I think we're yet to see if this is possible in practice with this virus but the short answer is no, it's not necessarily the case that everyone must get the virus before herd immunity is acquired.

It's also not necessarily the case that "everyone getting it" would actually provide protection either, this virus does mutate, and while I think experts haven't seen it mutate sufficiently to avoid new immunity (nor do experts even know how long or effective acquired immunity is for this virus), it's entirely possible that it could mutate in that way in the future, just as the flu and cold viruses do every year. In fact, again, I'm not an expert, but I believe that everyone getting it, would make it more likely that it would mutate in that way.

I am curious though, why you believe that a vaccine that is available in 18 months would take 2 years to give us herd immunity? I believe the 12-18 month estimate is for broad availability of the vaccine--and we're already 2 months into that timeline.

Don't most vaccines take about two weeks to generate immunity?  I guess longer if it's something that requires a booster.

Yes, they do take some time, I guess I haven't factored that in, but something like the flu vaccine is like two weeks as you said, it could be longer like the Hep vaccine, but even that, can get within a month or two on an accelerated schedule. No reason to suspect that would increase the timeline much more than 19 months, certainly it doesn't make 2 years "ambitious" in my opinion, unless MidTowner is thinking of something else.

[jamincan]

I think the ambitious part is having it complete testing and whatnot in that timeframe.

[ijmorlan]

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

Under 1. There is no such thing as R0 < 0.

[plam]

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

If you can do this in a local area then you can shrink the infected population then reduce restrictions while controlling new cases through tracing, testing, travel restrictions, and quarantining, you can be free of a virus, even without herd immunity. In theory at least--I think we're yet to see if this is possible in practice with this virus but the short answer is no, it's not necessarily the case that everyone must get the virus before herd immunity is acquired.

Yes, eradication is NZ's Plan A. That would require incoming travellers to do self-isolation so it wouldn't be good for the tourism industry but it's better than lockdown. They have been talking a bit about Plan B but that's not clear. The increase has been about 80 for a few days now and might go down next week if things go well, although there certainly has been some community transmission.

I think we got rid of the original SARS and MERS this way. They had more favourable conditions as well.

It's also not necessarily the case that "everyone getting it" would actually provide protection either, this virus does mutate, and while I think experts haven't seen it mutate sufficiently to avoid new immunity (nor do experts even know how long or effective acquired immunity is for this virus), it's entirely possible that it could mutate in that way in the future, just as the flu and cold viruses do every year. In fact, again, I'm not an expert, but I believe that everyone getting it, would make it more likely that it would mutate in that way.

I don't think we'd see 100% infection rates (which would be catastrophic, although less than 1918), but getting to 60% would slow down spread as well. I think this virus is less likely to mutate than others, although it can of course mutate as well.

I am curious though, why you believe that a vaccine that is available in 18 months would take 2 years to give us herd immunity? I believe the 12-18 month estimate is for broad availability of the vaccine--and we're already 2 months into that timeline.

I think even 18 months is pretty aggressive though we might be able to pull it off in this case having started phase I trials of some candidates.

[danbrotherston]

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

Under 1. There is no such thing as R0 < 0.

Yes, sorry, I meant under 1.

[danbrotherston]

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

If you can do this in a local area then you can shrink the infected population then reduce restrictions while controlling new cases through tracing, testing, travel restrictions, and quarantining, you can be free of a virus, even without herd immunity. In theory at least--I think we're yet to see if this is possible in practice with this virus but the short answer is no, it's not necessarily the case that everyone must get the virus before herd immunity is acquired.

Yes, eradication is NZ's Plan A. That would require incoming travellers to do self-isolation so it wouldn't be good for the tourism industry but it's better than lockdown. They have been talking a bit about Plan B but that's not clear. The increase has been about 80 for a few days now and might go down next week if things go well, although there certainly has been some community transmission.

I think we got rid of the original SARS and MERS this way. They had more favourable conditions as well.

It's also not necessarily the case that "everyone getting it" would actually provide protection either, this virus does mutate, and while I think experts haven't seen it mutate sufficiently to avoid new immunity (nor do experts even know how long or effective acquired immunity is for this virus), it's entirely possible that it could mutate in that way in the future, just as the flu and cold viruses do every year. In fact, again, I'm not an expert, but I believe that everyone getting it, would make it more likely that it would mutate in that way.

I don't think we'd see 100% infection rates (which would be catastrophic, although less than 1918), but getting to 60% would slow down spread as well. I think this virus is less likely to mutate than others, although it can of course mutate as well.

I am curious though, why you believe that a vaccine that is available in 18 months would take 2 years to give us herd immunity? I believe the 12-18 month estimate is for broad availability of the vaccine--and we're already 2 months into that timeline.

I think even 18 months is pretty aggressive though we might be able to pull it off in this case having started phase I trials of some candidates.

I generally agree with all this, but I do think the 12-18 month timeframe seems reasonable. There are already candidates in human trials (having skipped animal trials which is ... unusual), and if they were successful and easy to manufacture, 12 months would be...conservative. And there are a large number of candidates in development, so if one of them is successful, then 18 months is totally reasonable too.

Part of the reason for this, and one thing which really frustrates me, is that the usual 3-5 year timeline for creating a vaccine is substantially reduced because we already did some work on a SARS vaccine, and being for a virus in the same family, a lot of that work is transferable. However, that worked stopped when SARS was eliminated. Why wasn't that work continued, it was totally reasonable that another corona respiratory virus could come about, prudent policy would have been to develop that vaccine fully. Then our timeline for a vaccine here would be in the low months, like the yearly flu vaccine. I guess there was no profit in speculatively creating a vaccine in case we have a global pandemic...</cynical>

[MidTowner]

The answer to the first part of your question is, no, it doesn't have to remain in circulation.

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

If you can do this in a local area then you can shrink the infected population then reduce restrictions while controlling new cases through tracing, testing, travel restrictions, and quarantining, you can be free of a virus, even without herd immunity. In theory at least--I think we're yet to see if this is possible in practice with this virus but the short answer is no, it's not necessarily the case that everyone must get the virus before herd immunity is acquired.

It's also not necessarily the case that "everyone getting it" would actually provide protection either, this virus does mutate, and while I think experts haven't seen it mutate sufficiently to avoid new immunity (nor do experts even know how long or effective acquired immunity is for this virus), it's entirely possible that it could mutate in that way in the future, just as the flu and cold viruses do every year. In fact, again, I'm not an expert, but I believe that everyone getting it, would make it more likely that it would mutate in that way.

I am curious though, why you believe that a vaccine that is available in 18 months would take 2 years to give us herd immunity? I believe the 12-18 month estimate is for broad availability of the vaccine--and we're already 2 months into that timeline.

I understand that getting the ratio down to close to 0 is possible, but the possibility of doing that here in Ontario seems remote. Further, even if we could, we will remain open to other jurisdictions to some extent (I would say a large extent, depending on the perspective you take). There is no chance that we will close our borders completely. The deprivation wouldn't be worth it by anyone's estimation, I don't think. While there are cases somewhere, there is a chance that they will spread here. And that's even if

My understanding was that 12-18 months was an extremely ambitious timeline, possible but never before achieved, so this is why I think projecting the presence of the virus for two years seems logical. But I was under the impression that the timeline was ambitious for having the vaccine acceptable, not broadly available. If 18 months is the timeline for a vaccine to be validated and administered broadly, then I guess that's the timeline for the virus to be eradicated.

(By the way, both 18 months and two years are very long lengths of time to have anything like the kinds of controls and shutdown we're experiencing now...)

[danbrotherston]

The answer to the first part of your question is, no, it doesn't have to remain in circulation.

SARS (v1?) died out, because everyone who was sick with it got better or died, and there were no new patients, thus the virus died out (of the human population anyway). The key to doing this is controlling the R0. This is much harder for a virus like SARS-CoV-2 because it's R0 is much higher to begin with (for various reasons including pre- and a-symptomatic transmission), but it is still possible to get R0 under 0 and thus starve the virus of new hosts. China has already (or at least claimed to have) done this in specific areas.

If you can do this in a local area then you can shrink the infected population then reduce restrictions while controlling new cases through tracing, testing, travel restrictions, and quarantining, you can be free of a virus, even without herd immunity. In theory at least--I think we're yet to see if this is possible in practice with this virus but the short answer is no, it's not necessarily the case that everyone must get the virus before herd immunity is acquired.

It's also not necessarily the case that "everyone getting it" would actually provide protection either, this virus does mutate, and while I think experts haven't seen it mutate sufficiently to avoid new immunity (nor do experts even know how long or effective acquired immunity is for this virus), it's entirely possible that it could mutate in that way in the future, just as the flu and cold viruses do every year. In fact, again, I'm not an expert, but I believe that everyone getting it, would make it more likely that it would mutate in that way.

I am curious though, why you believe that a vaccine that is available in 18 months would take 2 years to give us herd immunity? I believe the 12-18 month estimate is for broad availability of the vaccine--and we're already 2 months into that timeline.

I understand that getting the ratio down to close to 0 is possible, but the possibility of doing that here in Ontario seems remote. Further, even if we could, we will remain open to other jurisdictions to some extent (I would say a large extent, depending on the perspective you take). There is no chance that we will close our borders completely. The deprivation wouldn't be worth it by anyone's estimation, I don't think. While there are cases somewhere, there is a chance that they will spread here. And that's even if

My understanding was that 12-18 months was an extremely ambitious timeline, possible but never before achieved, so this is why I think projecting the presence of the virus for two years seems logical. But I was under the impression that the timeline was ambitious for having the vaccine acceptable, not broadly available. If 18 months is the timeline for a vaccine to be validated and administered broadly, then I guess that's the timeline for the virus to be eradicated.

(By the way, both 18 months and two years are very long lengths of time to have anything like the kinds of controls and shutdown we're experiencing now...)

We don't have to get it close to 0, we have to get it under 1...I misspoke.

For getting it under 1, that's entirely possible, somewhere, I'm not sure where, estimated that with China's restrictions, which are obviously impossible here, it got down to 0.3, which results in a strong negative growth rate (I'm not sure I understand the math right, but I believe it would shrink at a rate close to the growth rate with an R0 of 3, which means it will shrink faster than it grew).

We don't have to get that low, but anything under 1 would result in negative growth. And yes, travel will be restricted for a long time, it will be very bad for tourist destinations. But with tracing and testing, it appears possible to keep this virus under control without strong local restrictions. This is exactly what many Asian countries are doing right now. Yes, they have differen contexts from ours, but if we can shut down half our economy for 6 months, I believe we can also implement similar controls. The even bigger benefit is that we have a model to follow for achieving that.

As for vaccines, an 18 month timeline would be extremely ambitious for a new vaccine, but again, much of the work has already been done, meaning a 12-18 month timeline is instead reasonable. If one of the first vaccines they are testing is successful, then 12 months is very much in play.

Edit: Some data: https://medium.com/@Joe_C_London/covid-1...9e485b0c63

While the author of this is not a healthcare expert, nor a contageous diseases expert (and can be a bit....overconfident sometimes) he generally backs up his opinions with numbers. If a peak has been reached in those countries, then the R is less than 1, so it's entirely possible. I think the restrictions are more severe in those countries, but it still demonstrates it is possible in western democracies.

[tomh009]

So, which local projects are now on hold due to today's announcement?

Well it would seem most of the condos can technically continue as "Residential construction projects where ... an above grade structural permit has been granted for condominiums, mixed use and other buildings" are exempt unless above grade structural permit doesn't mean what I think it does (which is quite possible!)

The only affected projects in DTK would 345 King W and and the Mayfair Hotel project, I think.

The reason for the wording is that if you don't have a building permit yet (demolition permit or foundation-only permit doesn't count) you don't get to continue construction.