More Talk About the Third Wave

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I was taking a closer look at the data for hospitalizations and ICU population and it does show clear evidence of a third wave. But there are some interesting differences between this one and two previous ones. The first one was back in April and centered on the NY metro area but hit other places on the East Coast as well as scattered spots in Washington, Louisiana, Michigan, Indiana and a few other places. Then we had the summer wave in the Sun Belt which was Florida, Texas, California, Arizona, Alabama, Mississippi, South Carolina and Nevada with other places tossed in as well. This third wave is the upper plains – the Dakotas, Montana, Wyoming, Nebraska, Utah, Idaho but we also have small increase in other places.

My data comes from the Corona Tracking project which uses volunteers to compile data from various state websites. It comes with all the problems associated with the various states including incomplete and inconsistent reporting but we deal with the data we have, not the perfect data we want.

From that site, I’ve graphed hospital census over time. This is a count of all patients in a hospital with a positive COVID result. I started where the data started. Before March 17th, they didn’t compile this type of data but there weren’t many COVID patients back then so I think this is fine.

You have the very scary looking ramp up in March when it looked like the hospitals were going to be overrun but it topped out around 60000 roughly on April 16th. Since the graph starts on March 17th, we went from essentially 0 to 60000 in a month. We stayed there for a week and then things started dropping to a low of about 28000 on June 20th. Then things started to climb again and it again looked like hospitals in Arizona, Florida and Texas were going to be in trouble. But the numbers of hospitalized patients topped out at around 60000 on July 23rd. Still, the number of hospitalized patients doubled in a month. The next low point was against right around 28000 (28608) and that happened on September 21. Things really didn’t start going up again until around October 4th.

So right now, we are 24 days into this third wave and the number of COVID patients sits at 45045. Are we headed to a much smaller peak and at a much slower rate. Or is this just the start of a longer wave? Right now, either is a possibility. But this third wave is looking different than the first two.

The next graph looks at the number of COVID patients currently in an ICU. Can’t explain the sharp increase in July. I doubt we have 4000 people admitted to ICUs across the country on one day so this is probably just some delays or glitches in reporting. The ICU data starts on March 26th – it may not have been closely tracked before then.

The patterns are similar. The first wave peaked at 15130 on April 16th but didn’t start dropping until April 26th. Again, it took about a month to hit a peak. The low was 5195 patients on June 21. As the second wave hit, the number of cases started to increase and peaked at 10,539 on July 29th but was basically at peak from July 22nd to August 2nd. Once again, we doubled in about a month. But it is also true that we didn’t get as high as the first wave even though the number of patients that were hospitalized was the same. I’d speculate that’s evidence of improved treatment.

The next low was 5974 on October 4th but there was a trough from September 19th until then. Again, it took about two months to reach that low but it also didn’t get as low as it did after the first wave. The number of COVID patients in an ICU has been climbing since October 4th and currently stands at 9034. As with hospitalized patients, it is too early to know if the third wave is going to stop short of the first two or if we are just in the beginning stages of a longer wave with a slower rate of increase. The answer won’t likely be clear until the end of November.

I want to talk about deaths next. But death figures that get reported by the various sites are not a true indicator because you have to go back to the date of death not when that death was reported. The current best source of information I’ve found is the CDC which does a provisional count of deaths due to COVID. The problem is that there are significant delays in state reporting so the recent data is not up to date. Right now, they’ve tracked data for 213,207 deaths so they are 20,000 that have yet to be accounted for.

But there is still information to be gained. In the first wave, the number of COVID deaths peaked at 17,079 for the week ending April 18th. But we have over 10,000 deaths from April 4th through May 9th. That dropped to a low of 3,791 for the week ending June 27th and then started back up as the second wave hit. The second peak was the week ending August 1 at 8,179 deaths. The week before had 8,099 deaths so not much different and we were above 7,000 deaths per week from July 18th through August 15th. The deaths were slightly behind hospitalizations in terms of peak and decline which would be expected. It should also be pointed out that the peak number of deaths was half what it was during the first wave.

As I said, the most recent data is not complete. For the week ending October 3rd, the number of COVID deaths was 3,501 and that increased to 3,566 the next week (ending October 10th). Due to the lag in reporting, no conclusions can really be drawn right now.

Lastly, I want to touch on cases. That could have come first since cases typically would be expected to lead both hospitalizations and deaths. But the ever changing denominator makes comparisons difficult.

I have been tracking this by week. In the first wave, when testing was limited, we hit 20% positive results for the weeks ending April 4th and April 11th. And it remained high with the first noticeable drop happening the week ending on April 25th. So positive results did peak before hospitalizations.

In the second wave, positive results started climbing during the week of June 27th and hit a peak of 7.9% during the week of July 18th. Really those first three weeks in July were all at the same rate so you could again say this peaked before hospitalizations. But the start of the increase in hospitalizations did coincide with the first jump in percent positive results.

That seems to be holding with this third wave. Hospitalizations started to rise on October 4th. During that week, we did see the percentage of positive results rise from 4.3% to 4.6% but it was hard to call that a real increase. That percentage has gone up the last two weeks to 5.1% and 5.9%. In the second wave, we saw a four week run before things started to go down. If this pattern holds, we’d expect percent positives to be a little higher this week and then slowly start to come down.

The overall percentage of positive results is lower for this third wave just like hospitalizations. But it is also true we are testing at a much higher frequency and probably testing many more true negatives with wide screenings in certain places.

To me, that creates a disconnect between the number of cases and the severity of those cases. We’ve hit an all time high in cases but that it not yet reflected in the number of people hospitalized or in an ICU. It is certainly possible that the shape of this wave is different and we will eventually see a bigger increase in the number of people hospitalized or in an ICU. It could also be true that if this wave follows the pattern of previous waves, that we are already close to the peak and things won’t get much worse from here.

Yes, I’m leaving you with a wishy washy non conclusion. There’s a reason for that. I think it is possible to look at the data and come to either conclusion. But each one is just a guess on future behavior which becomes less science and more projection. I see a reason to be concerned but not a reason to panic and I’ll leave it at that.

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