A lesson from Detroit

The Wall Street Journal yesterday posted a very instructive article about Detroit’s schools that shows it’s possible to reopen schools safely if we don’t rush into it and try to open up everything at once – as Israel did with disastrous results in May.

The article begins “When public schools here opened for summer instruction, protesters blocked school buses and challenged the opening in a lawsuit. In-person learning was too risky, they said, amid the pandemic. On July 21, a judge ordered the school district to test all in-person students for Covid-19. Only three students—less than 1% of those attending in-person classes—have tested positive, according to school authorities and the Detroit Health Department.”

What was the secret of their success? There’s nothing secret about anything they’re doing: daily temperature checks for all students, limiting class sizes, lots of hand sanitizer and social distancing. Note that one thing they weren’t doing was testing students for Covid-19 infection – they had to be ordered to do so by a judge, which seems strange. I assume this is because tests aren’t available in Detroit in the quantity needed, and/or that wait times for results are so long that testing doesn’t do much good. This is of course true in large parts of the country.

Students weren’t allowed to return to in-person school unless they were tested by July 23. Ideally, testing should be done regularly (once a week?) on students and adult staff members. And not having regular testing available – with 1-2 day turnarounds for results, if not 15-minute turnarounds – really needs to be a prerequisite for any large-scale return to schools, even if it’s not 100%.

Detroit offered both in-person and virtual summer school, so no child was forced to return in person against their parents’ will. One particular reason why there was so much interest in returning to class was that many students don’t have access to reliable internet connections or computers, or they have parents who really have to work and can’t help them with distance learning. The article points out that the suburban Detroit districts, where those problems are much less, have mostly remained 100% virtual this summer.

The point is obviously not to make schools completely virtual until the coronavirus is defeated or a reliable vaccine can be administered. It’s to reopen gradually. Since younger kids are a) much less likely to succeed with distance learning, and b) much less likely - it seems - to spread the virus if infected (this advantage seems to go away over age 10, and teenagers are if anything more likely to spread the virus than adults are), a good idea is to start with them, and also include older kids who need to be in school because of lack of internet service or parents who can’t help them, usually because they need to work.

Another solution (hopefully) is what New York is going to try: All students will be in school five days every two weeks, i.e. 2-3 days per week; they’ll be virtual the other days. So the schools will be open at exactly half strength.

It’s clear the solution is not to tell schools they need to reopen in full or lose some funding, as has so far been a provision in the Republican version of the new coronavirus relief bill. Virtual schools have similar expenses to online ones. And most importantly, forcing widespread full reopening will lead to a disastrous result like Israel’s – that’s guaranteed to make all schools virtual for a long time.

So both Detroit and (hopefully) New York City can offer good models for starting up schools safely. Of course, there is no safe model if Covid-19 cases are increasing in the area, or if regular testing (with 1-2 day turnarounds for results) isn’t available.

The numbers

These numbers are updated every day, based on reported US Covid-19 deaths the day before (taken from the Worldometers.info site, where I’ve been getting my numbers all along). No other variables go into the projected numbers – they are all projections based on yesterday’s 7-day rate of increase in total Covid-19 deaths, which was 5%.

Note that the “accuracy” of the projected numbers diminishes greatly after 3-4 weeks. This is because, up until 3-4 weeks, deaths could in theory be predicted very accurately, if one knew the real number of cases. In other words, the people who are going to die in the next 3-4 weeks of Covid-19 are already sick with the disease, even though they may not know it yet. But this means that the trend in deaths should be some indicator of the level of infection 3-4 weeks previous.

However, once we get beyond 3-4 weeks, deaths become more and more dependent on policies and practices that are put in place – or removed, as is more the case nowadays - after today (as well as other factors like the widespread availability of an effective treatment, if not a real “cure”). Yet I still think there’s value in just trending out the current rate of increase in deaths, since it gives some indication of what will happen in the near term if there are no significant intervening changes.

Week ending	Deaths reported during week/month	Avg. deaths per day during week/month	Deaths as percentage of previous month’s
March 7	18	3
March 14	38	5
March 21	244	35
March 28	1,928	275
Month of March	4,058	131
April 4	6,225	889
April 11	12,126	1,732
April 18	18,434	2,633
April 25	15,251	2,179
Month of April	59,812	1,994	1,474%
May 2	13,183	1,883
May 9	12,592	1,799
May 16	10,073	1,439
May 23	8,570	1,224
May 30	6,874	982
Month of May	42,327	1,365	71%
June 6	6,544	935
June 13	5,427	775
June 20	4,457	637
June 27	6,167	881
Month of June	23,925	798	57%
July 4	4,166	595
July 11	5,087	727
July 18	5,476	782
July 25	6,971	996
Month of July	26,649	860	111%
August 1	8,069	1,153
August 8	8,262	1,180
August 15	8,694	1,242
August 22	9,149	1,307
August 29	9,628	1,375
Month of August	38,167	1,231	143%
Total March – August	194,938

Red = projected numbers

I. Total deaths

Total US deaths as of yesterday: 160,326

Deaths reported yesterday: 1,358

Yesterday’s 7-day rate of increase in total deaths: 5% (This number is used to project deaths in the table above; it was 5% two days ago. There is a 7-day cycle in the reported deaths numbers, caused by lack of reporting over the weekends from closed state offices. So this is the only reliable indicator of a trend in deaths, not the three-day percent increase I used to focus on, and certainly not the one-day percent increase, which mainly reflects where we are in the 7-day cycle).

II. Total reported cases

Total US reported cases: 4,918,789

Increase in reported cases since previous day: 56,276

Percent increase in reported cases since 7 days previous: 9%  

III. Deaths as a percentage of closed cases so far in the US:

Total Recoveries in US as of yesterday: 2,482,899

Total Deaths as of yesterday: 160,326

Deaths so far as percentage of closed cases (=deaths + recoveries): 6%

For a discussion of what this number means – and why it’s so important – see this post. Short answer: If this percentage declines, that’s good. It’s been steadily declining since a high of 41% at the end of March. But a good number would be 2%, like South Korea’s. An OK number would be 4%, like China’s.

I would love to hear any comments or questions you have on this post. Drop me an email at tom@tomalrich.com