Monday, May 11, 2020

When Might New Cases Begin to Change With Reopening?

Like you I've been wondering when new Covid-19 cases will show up, if at all, from the various states reopening before public health experts suggest, and from truly insane numbskulls crowding into ice cream stores without even wearing a mask.

There's a time lag before they appear, but how much? This CNN article from May 5th provides some good information: "We won't know the impact of states reopening for weeks. Here are several reasons why."

They lay out the various delays between reopening and new cases start to appear, and give estimates for each delay:

time to notice new cases [deaths] = (incubation period) + (minor illness period) 
+ (test result period) + [(time to death)]

 = (2-14 days) + (a few days) + (a few days) + [(3 weeks)]

Let's take "a few days" to be 2 to 4. Average is 3 days.

So taking the average of the first three intervals above, we get about 14 days, or two weeks. About five weeks until new deaths would be noticeable.

There isn't any exact time of reopening -- it varies by state, and it varies by degree, that is, how much of the state's economy was reopened: just beaches, does it include restaurants, salons, saloons, tattoo parlors, etc. Do these places require masks and some form of social distancing? A temperature gun pointed at your forehead? Etc.

But two weeks would seem to be the minimum time before new cases would begin to show up, and even then it might be too small to notice. Just eyeballing it, perhaps additional new case will be noticeable by the end of May? But by then the first wave will have presumably declined more, temporarily hiding the beginning of the second wave.

Below is the current status (for the US), from worldometer. There's been a definite decline in new cases since about April 25th. It'd be a shame if that trend were to reverse. What's worse, economically -- another month or two of strict quarantine, or a virus that lingers for months and months, maybe reviving in the fall and winter. I understand some people and businesses are experiencing terrible stress financially. But another two months, and a plan to protect the elderly and immune-compromised, and much more testing and contract tracing, is far better than another Great Depression. I like the Democrats idea of giving $2000/person for another couple of months. But Senators like Lindsay Graham don't like because, as Business Insider wrote, he thinks it "would incentivize people to stay at home rather than return to work, to the detriment of small business owners." (But they'd still have money to spend.(?)) Graham said "he and his colleague Sen. Tim Scott [R-SC] would allow a $600 per week pandemic unemployment benefit to extend past July 'over our dead bodies.'" But he's fine with putting the risk on your dead body.

Trump has no plan as far as I can tell. No plan to protect the vulnerable, to ramp up testing, to ramp up contact tracing. Nothing. We're storming the beaches at Normandy after being dropped off in shorts and a t-shirt, with nothing but a cooler of pop and bologna sandwiches.

United States

30 comments:

Layzej said...

Ontario has just entered phase 2 of its reopening plan. We're ramping up testing in conjunction.

Our hospitals haven't been overwhelmed. Our new case rate is going down. So far so good. Time will tell whether we can ease off the restrictions without reversing the trend. Fingers crossed.

David Appell said...

Good luck. Please show that sane leadership helps.

Layzej said...

I never would have described our Premier Doug ford as sane. His brother Rob Ford ran Toronto and was involved in so many controversies that he became a regular target for Jimmy Kimmel.

He's shown leadership through this though.

David Appell said...

I was thinking of Justin Trudeau. Are most of the big decisions there made at the province level?

Layzej said...

Whether we are open or closed is up to the province, though the feds provide guidance. The borders are controlled by the Feds.

The feds have also provided an economic response plan that subsidizes wages so employers can keep workers on the payroll through the crisis, tops up wages for essential workers, and gives relief to those laid off.

David Appell said...

Do you mean the province borders, or the national borders (controlled by the federal govt)?

Is this right, below, that Canada is spending about C$250 B on COVID relief? If so that would be about 14-15% of GDP (?).

https://www.thestar.com/business/opinion/2020/04/13/financially-canada-is-in-good-standing-to-weather-the-pandemic-but-how-will-we-pay-for-it.html

Layzej said...

The national borders.

I'm not sure what the final number will be. GDP is about C$2.4 trillion (or was in 2018), so C$250 B is only about 10%. This more recent article says the response totals $146 billion (6% of GDP) in direct fiscal stimulus and brings the federal deficit to a total of $250 billion.

In that case our stimulus brings the debt to GDP ratio up from 4% to 10%. By contrast, USA had a deficit of 8% GDP before COVID and is raising that to 18.7% of GDP due to the 2.2 trillion corona response.

Of course GDP may be way down for both countries so it could be quite a bit worse that all that.

Layzej said...

Regarding "When Might New Cases Begin to Change With Reopening"

Noise in the data may result in a somewhat longer period before we can detect a change in the trend.

David Appell said...

Good point.

David in Cal said...

The negative impact of reopening may be offset in part by other things that are helping, such as more mask usage, warmer weather, and greater availability of tests. At least I hope so.

Cheers

Layzej said...

USA is about to pass Canada in tests/capita.

Canada: 30,356/million
USA: 30,017/million

Good news for USA. Canada needs to step up its game.

David Appell said...

David, more good points. Thanks.

Ned said...

USA is about to pass Canada in tests/capita.

Well, the number of tests needed is partly a function of the number of cases in a country. The US has a huge number of cases per capita, so it needs an unusually large number of tests (*still* significantly larger than we have).

If we had managed to keep the number of cases lower, we could get by with less intensive testing. But we didn't, so we can't.

Ned said...

This is a nice overview of the big picture in the USA:

We don’t have a president, or a plan
60 days into the coronavirus crisis, the White House does not have a plan, a framework, a philosophy, or a goal.


David Appell said...

https://www.washingtonpost.com/world/as-some-countries-ease-up-others-are-reimposing-lockdowns-amid-a-resurgence-of-coronavirus-infections/2020/05/12/6373cf6a-9455-11ea-87a3-22d324235636_story.html

I saw this story today.

My computer is in the repair shop, so all I have today is my phone and a keyboardless iPad, So I can’t do much more than I can dictate.

And even dictation isn’t that efficient. Maybe someday….

Layzej said...

Looks like Germany, Korea, and Iran are able to executed targeted actions rather than country wide lock downs. I hope we're able to follow the same path.

David in Cal said...

Ned - The current narrative is "we don't have a plan", but I don't understand it. The Task Force put out a detailed plan, calling for re-opening in three phases. They explained what was needed to move to each phase, addressed the continuing rise in testing availability and discussed how the US Public Health Service along with local Health Dept. personnel would do contact tracing for those who test positive. To me, this looks like a Plan.

Cheers

David in Cal said...

Another part of the Task Force plan is to produce results by locality. This helps Governors and other state officials decide what action should be taken locally. E.g., San Mateo County, where I live, is more shut down than various rural counties in CA. Los Angeles County says they'll be shut down through July.

Cheers

Entropic man said...

Ned

Here's your plan.It was given to the UK government just before the UK locked down.

https://www.imperial.ac.uk/mrc-global-infectious-disease-analysis/covid-19/report-9-impact-of-npis-on-covid-19/

Download Report 9 and look at Figure 4.

The plan is called adaptive triggering. When daily cases risk overloading your health service you trigger a tighter lockdown. A reduction in cases triggers an easing of the lockdown. You then repeat for as many cycles as necessary to reach herd immunity or a vaccine.

Essentially you thread the narrow path between a lot of extra deaths and economic collapse, for about 18 months.

Layzej said...

With some immunity the second and third wave may be quite a bit smaller.

Ned said...

DiC writes: "The Task Force put out a detailed plan, calling for re-opening in three phases."

Yes. The article I encouraged you to read cites and links to that. Did you read the article?

They point out that it's not really a plan containing mechanisms to make things happen; it's a set of guidelines for states to make decisions about when and how to re-open.

But the main problem is that the White House is not following that plan! They are encouraging states to ignore the guidelines and re-open immediately.

The President has rejected that plan, and there is nothing in its place.

So ... we don't have a plan.

David in Cal said...

Thanks, Ned, for the clarification. Saying "We don't have a plan" ends useful discussion. Saying, "We have a plan with the following flaws" facilitates discussion. E.g., we could discuss
1. To what degree are states following the Administration plan? My impression is that the plan is being followed to a great degree.
2. Does the federal government even have the Constitutional power to force states to follow their plan? Trump says he has that power; many others say he doesn't have that power.
3. Are state deviations from the plan working or are they making things worse?

Furthermore, IMHO there's a more important flaw: The Administration plan is a guess. We don't know whether the plan is sound, that is, whether it will actually work. Can we get the economy to recover without an unacceptable spread of the virus? Nobody knows. We know too little about the disease and too little about economic recovery from this extraordinary pandemic and extraordinary shutdown.

Cheers

Ned said...

We don't have a plan.

It's not a matter of "flaws". The Reopening America thing is not an actual plan in the sense of something that mobilizes resources to fight the pandemic. It's guidelines for states about various criteria that should be in place before they re-open. But there's not a plan to meet those criteria.

And as I said, the White House has rejected the Reopening America guidelines. Trump wants states to reopen immediately whether or not they have met the guidelines.

States are doing various things, based on what their governors etc. choose to do. But they're on their own. The President is just telling them all to re-open immediately.

That's not a plan. It's fifty states trying to figure out what to do on their own while the President stands on the sidelines inciting mob violence.

We don’t have a president, or a plan
60 days into the coronavirus crisis, the White House does not have a plan, a framework, a philosophy, or a goal.

David in Cal said...

Ned - The President is telling the states to follow the Administration plan. I heard him say that.

Cheers

Ned said...

Trump has specifically called on Pennsylvania, Virginia, Michigan, and Minnesota to re-open. *None* of them meet the guidelines (virtually *no* states do yet). The president is irresponsible and a menace to the nation.

Oddly enough, the states he's demanding reopen immediately all have Democratic governors. Why do you think that is?

There is no plan. States are having to figure it out for themselves, while the President deliberately riles up his followers against the governors.

David in Cal said...

Ned -- the standards for Phase 1 re-opening are at https://www.whitehouse.gov/openingamerica/ Given the huge amount of testing and the relatively low hospital usage, I would expect these states to easily satisfy those two criteria.

I do not have state by state trends in new cases or % of positive test results. I do know that these are decreasing nationwide.

I have no information regarding the trend in influenza-like cases or covid-like syndromic cases.

Even if an entire state fails to meet one of these criteria, I wonder whether there are counties within the state that do meet these criteria, and so could be re-opened.

I live in San Mateo County, CA -- an area with a pretty high incidence. Nevertheless, we have been in Phase 2 for some time and will be moving to Phase 2 next week.

Cheers

Ned said...
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Ned said...
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Ned said...

(minor issues with posting)

Only Kentucky And North Dakota Meet White House Criteria For Reopening, Data Says

That was published on May 14. Since then, both ND and KY have backslid, and neither of them now meets the criteria for reopening.

Tracking state progress toward meeting guidelines for reopening:
https://www.covidexitstrategy.org/

"no state had held on to the criteria for more than 3 days straight."

The President is urging states to re-open before they meet the guidelines published by his own administration.

And, again, this is not a plan for combating the virus. It's just guidelines for when states should consider re-opening. And neither the President nor many state governments are following them.

So ... there is no plan.

David in Cal said...

Thanks for the link, Ned. One area of disagreement involves the adequacy of testing. Unlike the other criteria, this one is not objective. It says, "Robust testing program in place for at-risk healthcare workers, including emerging antibody testing."

Several weeks ago, if I recall correctly, Dr. Birx said that we then had enough testing available so that every state (or almost every state) satisfied the Phase 1 requirement. Since then, the daily number of tests more than doubled, from around 150,000 to over 350,000.

OTOH the Forbes article says, "The testing metric each state is measured on includes the 500,000 per day national target suggested by the Harvard Global Health Institute, adjusted to each state based on its population."

Cheers