Breakthrough Events February 2023, Ages 50 to 64

Definitely middle-agers up next.  And here too there is currently zero protection from infection and very, very little from hospitalization.

Dave’s notes:

1. The following charts show how vaccination status affects the risk of testing positive, being hospitalized, or dying of Covid for the 50-64 age group. We find that vaccination and boosting appear to offer benefit to the 50-64 age group until March of 2022. Since March 2022 vaccination or boosting appears to offer little benefit in reducing the numbers of cases, hospital admissions, or deaths.
2. We have recently documented fairly extensively the issue of the population basis used by the Minnesota Department of Health (MDH) affecting the 65+ age group. Note that MDH calculates the unvaccinated population by starting with the estimated age group population and then subtracting the vaccinated and the boosted populations. Any discrepancy made in the initial population assumption then directly causes the same size discrepancy in the size of the unvaccinated population. In contrast to the 65+ age group, which has been increasing at a steady rate since 2020, the 50-64 age group has been relatively constant population since 2014. Discussion on this issue can be found here: https://healthy-skeptic.com/2022/12/02/census-estimate-background/ .  We also discuss the impact on the 65+ age group here: https://healthy-skeptic.com/2022/12/06/the-real-vax-effectiveness-rates/. In contrast to the impact seen for the 65+ age group, the choice of population estimate for the 50-64 age group makes very little difference to the final result.
3. This post is an update to the chart set for the 50-64 age group most recently published on 1/11/2023 here: https://healthy-skeptic.com/2023/01/11/breakthrough-events-ages-50-to-64-4/. We will display the rates per 100k which result from using the 2021 American Community Survey (ACS) 1-Year population estimate, as well as MDH’s published data using the 2019 ACS 5-Year population estimate.
4. There are 9 charts in this set, 3 charts each for cases, hospital admissions, and deaths. Each set of 3 charts consists of the actual events per week (cases, admissions, or deaths); the rate per 100k each week, and the proportion of events compared to the proportion of the vaccinated population. Note that on the rate per 100k charts for cases, hospital admissions, and deaths we are displaying both MDH’s rates (solid lines) and our calculated rates per 100k using the ACS 2021 1-Year population estimate for 2021 (dotted purple lines). For the proportion charts are only displaying data using the 2021 ACS 1-Year population.
5. Fig. 1, Minnesota Covid Cases Per Week, 50-64 Age Group: This chart plots the number of cases in the 50-64 year old age group per week among the unvaccinated, vaccinated but not boosted, and vaccinated and boosted populations each week. These cases are plotted from the MDH data files without modification. The number of cases continue to follow a decreasing trend since the May 2022 peak.
6. Fig. 2, Minnesota Covid Cases Per 100k Per Week,50-64 Age Group: This chart displays the case rates per 100k for each subgroup in the 50-64 age group. The impact of the choice in population estimate is minimal, as the unvaccinated case rate the 2019 ACS 5-Year population as used by MDH (solid purple line) almost exactly matches the case rate calculated with the 2021 ACS 1-Year population estimate (dotted purple line). We can see that initial vaccination without booster shots ceased to cause a lower case rate in December 2021, compared to the unvaccinated. Since August 2022 the unvaccinated, vaccinated, and the boosted all have almost identical case rates, meaning that vaccination status has little to no effect on testing positive for Covid.
7. Fig. 3, Minnesota Proportion of Covid Cases by Vaccination Status, 50-64 Age Group: This chart displays the proportion of the 50-64 year old population who are unvaccinated (solid purple), vaccinated but not boosted (solid blue), and vaccinated and boosted (solid gold). This chart uses the 2021 ACS 1-Year estimated population to calculated the size of the unvaccinated group. A group is under-represented whenever the dashed line is below the solid line of the same color. For example, the boosted proportion of cases (dashed gold line) is lower than the boosted proportion of population until March of 2022, then these proportions are equal. After March 2022 it does not appear that boosters provide any significant protection from testing positive for Covid. Meanwhile, the proportion of cases among the vaccinated (dashed blue line) is higher than the vaccinated proportion of population (solid blue line) since October 2021.  Note that since November 2022 the proportion of cases have been converging on the proportion of vaccination. This indicates that vaccination status has little to no effect on the likelihood of testing positive for Covid in recent months.
8. Fig. 4, Minnesota Covid Hospital Admissions Per Week 50,64 Age Group: This chart plots the number of hospital admissions in the 50-64 year old age group per week among the unvaccinated, vaccinated but not boosted, and vaccinated and boosted populations each week. These admissions are plotted from the MDH data files without modification. Hospital admissions, especially for the boosted, have been gradually increasing from April 2022 to December 2022, before dropping sharply in recent weeks.
9. Fig. 5, Hospital Admissions Per 100k Per Week, 50-64 Age Group: This chart displays the hospital admission rates per 100k for each subgroup in the 50-64 year old age group. The impact of the population estimate shows up minimally in this chart, just as it did in Fig. 2 for case rates. Using the 2021 ACS 1-Year  population estimates has little effect on admissions per 100k (dotted purple line) compared to the rates published by MDH (solid purple line). Admissions rates for all three vaccination statuses are very similar since March 2022, with the admission rates for the boosted perhaps being slightly lower on average than for the vaccinated or unvaccinated.
10. Fig.6, Minnesota Proportion of Hospital Admissions by Vaccination Status, 50-64 Age Group: This chart displays the proportion of hospital admissions compared to the proportion of the population for the unvaccinated, vaccinated, and boosted, for the 50-64 year old age group. The boosted have a lower proportion of admissions (dashed gold line) than the boosted proportion of the population (solid gold line), showing that boosters appear to have a positive effect. Throughout the pandemic the boosted have generally had a lower proportion of admissions than the proportion of vaccination.
11. Fig. 7, Minnesota Covid Deaths Per Week, 50-64 Age Group: This chart plots the number of deaths in the 50-64 year old age group per week among the unvaccinated, vaccinated but not boosted, and vaccinated and boosted populations each week. The number of deaths each week are plotted from the MDH data files without modification. Since March 2022 there have been relatively few Covid deaths, regardless of vaccination status.
12. Fig. 8, Minnesota Covid Deaths Per 100k Per Week, 50-64 Age Group: This chart displays the death rates per 100k for each subgroup in the 50-64 age group. There is little difference in the death rates per 100k among the three groups since March 2022, which are all very close to zero.
13. Fig. 9, Minnesota Proportion of Covid Deaths by Vaccination Status, 50-64 Age Group: This chart displays the proportion of deaths compared to the proportion of the population for the unvaccinated, vaccinated, and boosted, for the 50-64 age group. Until March 2022 the unvaccinated proportion of deaths (dashed purple curve) is significantly higher than the unvaccinated proportion of the population (solid purple curve), meaning the unvaccinated were more at risk. Since March 2022 there are so few deaths that it is difficult to interpret the effectiveness of vaccination or boosters.
14. All data is obtained from the Minnesota Department of Health (MDH) Vaccine Breakthrough Weekly Update web site https://www.health.state.mn.us/diseases/coronavirus/stats/vbt.html. A data file on this site, vbtadultcirates.xlsx, contains all of the age group data.
15. MDH defines the fully vaccinated (what we have termed vaccinated but not boosted) as those who have not received a booster after completing their primary vaccination series, and had been vaccinated at least 14 days prior to testing positive.
16. MDH defines the boosted as those who have received any additional vaccination shots after completing their primary vaccination series, and also received the booster at least 14 days prior to testing positive. In addition, booster doses were only counted after 8/13/2021, the date the CDC first began recommending booster shots.