Breakthrough Events, Ages 50 to 64

For this older middle-aged group, vax also do nothing to limit infection risk and appear to have minimal impact on hospitalizations.

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, similar to the benefit received by the 65+ age group. 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 in 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 12/14/2022 here: https://healthy-skeptic.com/2022/12/14/breakthrough-events-as-of-week-of-december-8-ages-50-to-64/. 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 we are only displaying data using the 2021 ACS 1-Year population.
5. Fig. 1: This chart plots the number of cases in the 50-64 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, although the numbers of cases have been relatively constant in the last several months.
6. Fig. 2: 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 with 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: This chart displays the proportion of the 50-64 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 the 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 in the most recent weeks of data that the proportion of cases almost exactly matches the proportion of vaccination for each vaccination status. This indicates that vaccination status has little to no effect on the likelihood of testing positive for Covid.
8. Fig. 4: This chart plots the number of hospital admissions in the 50-64 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. In contrast with cases, seen to be gradually decreasing for several months in Fig. 1, hospital admissions among the boosted have recently exceeded the May 2022 peak. Admissions for the unvaccinated and the vaccinated have been largely constant since May 2022.
9. Fig. 5: This chart displays the hospital admission rates per 100k for each subgroup in the 50-64 age group. 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, although often the admission rates for the unvaccinated are slightly higher than the rates for the vaccinated or the boosted.
10. Fig.6: 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 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. For the week of 12/11/2022 the unvaccinated made up 22% of the age group and accounted for 23% of the admissions. The boosted made up 61% of the age group but accounted for only 48% of the admissions.
11. Fig. 7: This chart plots the number of deaths in the 50-64 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: 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.
13. Fig. 9: 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.