Full Version: The latest wave is climbing super fast
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I noticed that Santa Clara County's new cases had gone up 50% in a week (!!).  That, plus 1000/day in L.A., and reports of overcrowded ICUs in the US Midwest, brought home that we are into a new wave of COVID, no matter what our %-vaccinated numbers are.

So, I went to look for R-numbers where I had seen them before.  Seems bit-rot may have set in.  But, I dug a little deeper.
Although the graphs at  are sadly out of date, the data collection is working for some areas.  Here are current R numbers from that site (for counties where data is current):  

Alameda: 1.398  7/1
Contra Costa:  1.397  7/10
Los Angeles:  1.701  7/9  (1st day of the three 1000+ cases)
Orange: 1.575 7/2
Ventura: 1.037 7/2
San Bernardino: 1.760 7/8

Those are very high rates of spread.

For L.A., if R=1.7 continues, and the cycle is once  a week, here are rough numbers for daily cases on Fridays for the next month:
July 9:  1,000
July 16: 1,700
July 23: 2,890
July 30: 4,913
Aug 6: 8,352   L.A. didn't hit this number until Dec. 4, 2020
   (i.e., August 2021 may look worse than Dec. 2020 -- R was only 1.26 then)

[Image: LACo-R.png]

I suspect we're in for some more NPI restrictions.   (And, kudos to L.A. for advising about masks.  That's the least intrusive restriction, but it seems unlikely that it is being effective.)

When and how CA restrictions are put in place will likely impact & be impacted by the recall election of the Governor in mid-September.   If I were the Governor, I'd put something in place this week.  If the state waits to August, it will likely still be bad in early September (and for the all-important school opening), which might influence voters on Sep. 14.

(Note that I am being careful NOT to express any opinion about the Governor or that election.  Let's avoid political discussion.)

CovidActNow also gives R values (as "Infection Rate"), from week-old data.
The rate of spread is less than a week ago, but still faster than any prior time during the pandemic (except maybe the first month when testing was new).  For instance, Santa Clara county was at 23 cases around May 30, at 34 a week or so ago, and now at 76.  That's a daily rate over a 7-day average, as of a few days ago, so today's case rate is likely a good bit higher.  CovidActNow indicates a growth rate of 1.34 in SCC (higher than the previous high of 1.32 a year ago).

I think people think that the vaccination rate is going to save some areas during this wave.  At least at this time, the vaccination rate has only a weak association versus the rate of spread.  In this graph, a spread of 1.35 means that each infected person is infecting 1.35 people (so infections are growing about 35% a week).
The data points are for the states, with data from as of Saturday, July 17.  Note that all states are seeing cases grow.

 [Image: State-Spread-Vs-Vaccine-Rate.png]

In this graph of rate of infection of the population versus vaccination rate,  you can easily see the expected association.
[Image: States-case-rate-Vs-Vaccine-Rate.png]
Definitely looks like another wave.  Coming at a time when few of us want to return to social distancing--starting with me.   Will be interesting to see how governments respond.  UK is opening up tomorrow and I doubt they will slow that down, preferring to rely on the vaccines.  I believe LA county is now requiring masks indoors.   did not hear if indoor dining restrictions are in effect.
The Contra Costa County site at, which has a graph breaking down new case rates for the vaccinated and unvaccinated separately, shows the rate for the vaccinated on July 14 as 3.2/100k/day. This is almost as high as the rate for the whole county around July 4. The rate for the unvaccinated is shown as 24.5/100k. Note that the data for the last week is incomplete so these numbers may go up some more.
We all get to review our lessons on exponential growth!
82Card, thanks for the link.

The politicians are blaming those who haven't gotten their vaccinations. Yes, that's a major part of the problem, but those with vaccinations will be getting sick too.

A confounding problem may be that those with vaccinations are less likely to get tested ("Oh, it's just a cold. I'm vaccinated") than those without vaccines, resulting in a lower accounting for those vaccinated. CoCoCo is showing a ratio of 22.4/3.3 for July 14 = 6.8 (for a vaccine effectiveness of 85%, which is higher than studies have shown).