Data on impact of countermeasures on virus spread?

Recently, I’ve been running into the argument that the current resurgence of cases proves that the corona-related restrictions (mask-wearing, contact restrictions, and so on) don’t work. Now, this argument is blatantly fallacious, of course: we don’t know how bad the current caseload would be without the measures, so we don’t have a baseline to compare against. Plus, if the measures are ineffective, what caused the caseload to diminish initially? Did the virus just go for a summer break?

Anyway, that’s not my topic for this thread. Rather, since pointing out the fallacious nature of this argument doesn’t seem to do much (I know, I know, I was as surprised as you are), I’d like to at least meet it with some data—ideally in the form of easily-understood infographics and the like, since nothing else seems to have much of a chance in capturing anybody’s attention.

One interesting approach I’ve used is pointing out that while we don’t have baseline data in the case of corona, we do in the case of other, similarly transmitted viruses. So, for instance, flu season has been a virtual no-show in the southern hemisphere:

So clearly, masks, contact restrictions, and the like are effective at slowing virus spread. But still, it would be preferable to have data directly applicable to coronavirus. That can’t obviously be a comparison like the above one, but it seems that there should, by now, be enough data on how well and what restrictions were observed in certain places, and what effect that had on the local corona spread. Something like a correlation between how well the public adhered to wearing masks, and the rate of infection.

For one, there’s this meta-analysis that concludes that mask-wearing is more effective in Asia than in Europe, which might be indicative of the fact that it’s already been a part of local culture there:

But does anybody know of anything more readily appreciated? I mean, I know I’m sorta asking for something near-impossible here, a study that’s scientifically well done and whose conclusions can also be boiled down to social-media compatible infographlet form, on a topic that’s currently very much in development and hampered by oodles of confounding variables across different regions, but hey—a man can hope… :wink:

As you noted, it’s hard to get hard statistical data, but this article says that the reason that California’s coronavirus stats are going down is due to mask wearing and social distancing.

The article also contrasts other states that have done less social distancing and quarantine measures that have led to higher rates of infection.

Anecdotally, when I read this article or one like it on Reddit, most people who wrote about mask wearing in California said that most places are mask wearing compliant. There are still a few places that are rebelling, but compared to their travels to other states, the Californians said that mask wearing compliance in California is much higher.

I might suggest you have a look at the state of Victoria, Australia. We had a first wave in March and April; some significant restrictions took it down to almost nothing.
Then there were some screwups, and a second wave hit starting in July. At that point, the restrictions really came down; the city of Melbourne was locked off from the rest of the state, masks became mandatory, businesses shut down, etc.
Now, we’re just about back to good, and the restrictions are starting to come down…slowly.
This page gives you an overview of the cases in Victoria.
This page gives the “Roadmap to Recovery”, a listing of the restrictions, and the trigger points to move onto the next stage.
I’ll tell you, it’s real nice that we’ve gone from up to 675 new cases a day, down to one or two. It’s taken a couple of months, but we’re getting there.

I just want to be clear, that the first wave was almost nothing. A tiny number of local infections. The ‘wave’ in hospitalizations was almost entirely due to imported cases.

The ‘second’ wave was an exponentially increasing number of local infections that overwhelmed the contact tracing and quarantine system, and was only stopped by closing non-essential local businesses.

Unfortunately, it’s not possible to separate out the effect of the multiple different restrictions that were imposed. We’ve had outbreaks in meatworks, and distribution centers (warehouses), and bars, and in families, so closing those and restricting family events clearly had an effect: the effect of masks is only surmised, the effect of some of the other restrictions (travel, golf, landscaping) is only guessed at.

The overall effect here, as in China, is clear: if you put enough restrictions in place, exponential increase turns into exponential decrease.

I think the interesting lesson is that it took a long time for the number of cases to go back close to zero, even with legal restrictions. What are you going to do about the police, and nurses, and security guards, and food delivery, and gasoline and electricity? It’s very difficult to put a whole city in jail for 14 days, and if you did, who does the testing-- so that has to be 28 days. We had to leave the city functioning, and it’s taken a very long time for the case numbers to drop down far enough for them to consider re-opening bars.