Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention Approach

Throughout the pandemic, individuals 65 years and older have contributed most COVID-19 related deaths. To best formulate effective vaccination and other prevention policies to protect older adults, large scale observational studies of these higher risk individuals are needed. We conducted a Vaccine...

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Main Authors: Bettina Experton, Adrien Elena, Christopher S. Hein, Dale Nordenberg, Peter Walker, Blake Schwendiman, Christopher R. Burrow
Format: Article
Language:English
Published: MDPI AG 2022-11-01
Series:Biology
Subjects:
Online Access:https://www.mdpi.com/2079-7737/11/12/1700
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author Bettina Experton
Adrien Elena
Christopher S. Hein
Dale Nordenberg
Peter Walker
Blake Schwendiman
Christopher R. Burrow
author_facet Bettina Experton
Adrien Elena
Christopher S. Hein
Dale Nordenberg
Peter Walker
Blake Schwendiman
Christopher R. Burrow
author_sort Bettina Experton
collection DOAJ
description Throughout the pandemic, individuals 65 years and older have contributed most COVID-19 related deaths. To best formulate effective vaccination and other prevention policies to protect older adults, large scale observational studies of these higher risk individuals are needed. We conducted a Vaccine Effectiveness (VE) study during the B.1.617.2 Delta variant phase of the pandemic in July and August 2021 in a cohort of 17 million Medicare beneficiaries of which 5.7 million were fully vaccinated. We found that individuals fully vaccinated with the Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273 vaccines in January 2021 had 2.5 times higher breakthrough infections and hospitalizations than those fully vaccinated in March 2021, consistent with waning of vaccine-induced immunity. Measuring VE weekly, we found that VE against hospitalization, and even more so against infection, increased from July 2021 through August 2021, suggesting that in addition to the protective role of vaccination, increased masking or social distancing might have contributed to the unexpected increase in VE. Ongoing monitoring of Medicare beneficiaries should be a priority as new variants continue to emerge, and the VE of the new bivalent vaccines remains to be established. This could be accomplished with a large Medicare claims database and the analytics platform used for this study.
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spelling doaj.art-b8c479f95a874e8f9a8b615f410f3af22023-11-24T13:21:52ZengMDPI AGBiology2079-77372022-11-011112170010.3390/biology11121700Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention ApproachBettina Experton0Adrien Elena1Christopher S. Hein2Dale Nordenberg3Peter Walker4Blake Schwendiman5Christopher R. Burrow6Humetrix Inc., Del Mar, CA 90214, USAHumetrix Inc., Del Mar, CA 90214, USAHumetrix Inc., Del Mar, CA 90214, USAThriive, Inc., Bronx, NY 10463, USAUS Navy, Washington, DC 20376, USAHumetrix Inc., Del Mar, CA 90214, USAHumetrix Inc., Del Mar, CA 90214, USAThroughout the pandemic, individuals 65 years and older have contributed most COVID-19 related deaths. To best formulate effective vaccination and other prevention policies to protect older adults, large scale observational studies of these higher risk individuals are needed. We conducted a Vaccine Effectiveness (VE) study during the B.1.617.2 Delta variant phase of the pandemic in July and August 2021 in a cohort of 17 million Medicare beneficiaries of which 5.7 million were fully vaccinated. We found that individuals fully vaccinated with the Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273 vaccines in January 2021 had 2.5 times higher breakthrough infections and hospitalizations than those fully vaccinated in March 2021, consistent with waning of vaccine-induced immunity. Measuring VE weekly, we found that VE against hospitalization, and even more so against infection, increased from July 2021 through August 2021, suggesting that in addition to the protective role of vaccination, increased masking or social distancing might have contributed to the unexpected increase in VE. Ongoing monitoring of Medicare beneficiaries should be a priority as new variants continue to emerge, and the VE of the new bivalent vaccines remains to be established. This could be accomplished with a large Medicare claims database and the analytics platform used for this study.https://www.mdpi.com/2079-7737/11/12/1700COVID-19/epidemiology/prevention & controlSARS CoV-2Delta variantB.1.617.2COVID-19/breakthrough infectionBNT162b2 vaccine
spellingShingle Bettina Experton
Adrien Elena
Christopher S. Hein
Dale Nordenberg
Peter Walker
Blake Schwendiman
Christopher R. Burrow
Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention Approach
Biology
COVID-19/epidemiology/prevention & control
SARS CoV-2
Delta variant
B.1.617.2
COVID-19/breakthrough infection
BNT162b2 vaccine
title Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention Approach
title_full Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention Approach
title_fullStr Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention Approach
title_full_unstemmed Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention Approach
title_short Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention Approach
title_sort enhanced vaccine effectiveness during the delta phase of the covid 19 pandemic in the medicare population supports a multilayered prevention approach
topic COVID-19/epidemiology/prevention & control
SARS CoV-2
Delta variant
B.1.617.2
COVID-19/breakthrough infection
BNT162b2 vaccine
url https://www.mdpi.com/2079-7737/11/12/1700
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