Indiana Covid Update (1/7/2023)

This winter Covid wave has been the mildest so far and has (fingers crossed) probably peaked.

This Covid wave is mildest winter wave we have had since the virus was first identified, certainly in terms of severe illness and death but likely also in terms of infections. And, it looks like there is compelling evidence that we have passed the peak of the wave. But first, below is the latest dashboard of Covid metrics for Indiana.

Data from the final weeks of a year are always difficult to interpret. We know there is a holiday effect that reduces testing, cases, hospital admissions and even deaths(!). But, we now have data far enough into January (through Jan. 4th for wastewater data and Jan. 5th for hospital data) that I think it’s safe to interpret this data as showing a significant decline in infections, and likely the peak of the winter wave.

As I’ve said before, it has become almost impossible to draw any meaningful conclusions about infections using official case data. While it can be useful for trends (are cases rising or falling?), case data are often incomplete (require a long embargo period) and delayed (Indiana only reports case data once per week). For example, on the dashboard above, the latest data we have is from January 1st, which is likely still being affected by the holidays. On top of this, many/most positive cases being found are detected through at-home testing, which doesn’t get reported or officially recorded at all.

Instead of cases or positivity rate, the two best measures we have now are wastewater viral concentration (a measure of actual infections out there) and hospital admissions (a measure of the severity of actual infections out there). Below I look at both of these.

Wastewater data are the best measure of infections

The most reliable indicator we have of the current levels of Covid infections out there is wastewater viral concentration. There are 11 Indiana counties for which we have data for Jan. 4th, and in these counties, wastewater viral concentration has been falling consistently (down 18% from a week ago and 10% from two weeks ago). While not everywhere collects and reports wastewater viral data, you may be able to look up where you live using one of the following resources:

1. BioBot Analytics (easiest to use, has data at the county-level for 18 Indiana counties, includes variant proportions)

2. Indiana State Department of Health Wastewater Dashboard (easy to understand, provides data at the Indiana health district level, has data for four of the ten health districts).

3. CDC Wastewater Surveillance Dashboard (not so easy to understand, provides data at the site-level which can be difficult to interpret)

Hospital admissions are the best measure of severe infections

If wastewater data estimates of the amount of infections out there, hospital admissions for Covid are the best estimate of how severe these infections are. The chart below shows average daily hospital admissions for Covid in Indiana since October 2022 (darkest blue line) compared with the same time period in the previous two years.

Average daily hospital admissions for Covid in Indiana peaked at 140/day on December 31st and during the four days of data since, have fallen to 120/day. This decline, coupled with a similar decline in waste viral concentration, appears to me to be compelling evidence that we have made it through the worst of this winter wave. This would make the peak of the winter wave several weeks earlier than previous years (last year the winter wave didn’t peak until late January and the year before not until mid January), but that would be consistent with the wave beginning earlier this year.

It is always possible there is a hidden second peak that could happen later this month, but with the declining wastewater viral concentration I think the odds of that decrease every day. If this holds as the peak of the winter wave, then this winter will be the mildest Covid winter wave so far, and by a huge margin. Certainly in terms of severe infections and deaths, but also likely in terms of infections (and thus risk of PASC).

The mildest winter wave so far

During November and December of 2022, there were 6,234 people admitted to Indiana hospitals for Covid. That is 64% fewer than 2021 and 71% fewer than 2020. This is a clear sign that protection gained from vaccination (and to some extent previous infections) has dramatically reduced the amount of severe illness Covid causes. Here are the total hospital admissions for Covid in Indiana during November and December for the following years:

• In 2020: 21,499 admissions

• In 2021: 17,087 admissions (21% fewer than 2020)

• In 2022: 6,234 admission (71% fewer than 2020, 64% fewer than 2021)

The decline in deaths from Covid is even more significant. During November and December of 2022, there were 475 deaths in Indiana from Covid. That is 82% fewer than in 2021 and 90% fewer than in 2021 during those same months.

In addition, of these 475 deaths, the majority (53%) were among those aged 80 years or older. 78% were among those aged 70 years or older. There were ZERO deaths among those aged 0-29 years. While every death is an unfortunate loss of life, we’re no longer seeing deaths among younger Hoosiers. For contrast, last year during November and December there were nine kids (age 0-19) and another 20 young adults (aged 20-29) who died from Covid.

Here are the total deaths from Covid in Indiana during November and December of the following years:

• In 2020: 4,944 deaths

• In 2021: 2,600 deaths (47% fewer than 2020)

• In 2022: 475 deaths (90% fewer than 2020, 82% fewer than 2021)

While 475 deaths during November and December is higher than we should be willing to accept, it’s a massive improvement over the previous two years.

What lies ahead?

It’s impossible to predict what lies ahead, but I’ll share what I think is most likely. The latest Omicron subvariant (XBB.1.5) is rapidly becoming the dominant variant in the United States. However, remember that at any given moment SOME variant will be the dominate variant and becoming the dominant variant does not necessarily mean overall infections are even up. So far, there is no evidence that XBB.1.5 is resulting in more severe health outcomes (just as there wasn’t either for BQ.1 and BQ.1.1).

In my personal opinion (please take with a huge grain of salt), as the population continues to be exposed to more Covid (and more variants) I think we will see the severity of illness from Covid continue to fall. There’s always a possibility that some new super-variant might suddenly develop, but the longer we go without that happening the safer we feel (for better or for worse). Instead, I think we will transition from talking less about hospitalization and death from Covid (as these decline) to talking more about potential long-term health consequences from Covid (PASC). While Covid isn’t over and won’t be going away for a long time (probably not ever), this would be a win.

For the immediate future, I think it’s likely we’ll see the winter wave subside during the rest of January and through February and March. If our previous experience holds, it’s probably reasonable to anticipate another wave (probably related to a new variant) in April or May.

Thanks for reading this far! If you have questions or comments, post them below!