Objective: To estimate the effectiveness of messenger RNA (mRNA) booster doses during the period of Delta and Omicron variant dominance.
Design: We conducted a matched test-negative case-control study to estimate the vaccine effectiveness (VE) of three and two doses of mRNA vaccines against infection (regardless of symptoms) and against COVID-19-related hospitalisation and death.
Setting: Veterans Health Administration.
Objective: To estimate relative effectiveness of the booster mRNA Covid-19 vaccination versus the 2-dose primary series for both Delta and Omicron variants with self-controlled study design.
Methods: We used the Veterans Health Administration (VHA) Corporate Data Warehouse to identify U.S.
This case-control study examines estimated COVID-19 messenger RNA vaccination effectiveness against SARS-CoV-2 infection from January to September 2021 among fully vaccinated male veterans aged 65 years or older.
View Article and Find Full Text PDFImportance: Effectiveness of mRNA vaccinations in a diverse older population with high comorbidity is unknown.
Objectives: To describe the scope of the COVID-19 vaccination rollout among US veterans, and to estimate mRNA COVID-19 vaccine effectiveness (VE) as measured by rates of SARS-CoV-2 infection.
Design, Setting, And Participants: This matched test-negative case-control study was conducted using SARS-CoV-2 test results at Veterans Health Administration sites from December 14, 2020, to March 14, 2021.
A Taiwanese cohort study found that symptomatic herpes simplex virus (HSV) infection was associated with a threefold increased risk of developing dementia; however, antiherpetic medication reduced the risk by 90%. Our aim was to verify and further investigate this finding in the US Veteran population using comprehensive electronic medical records from the Veterans Health Administration (VHA). Eighty-seven thousand six hundred eighty-seven Veterans aged 50 or older with symptomatic HSV-1/HSV-2 infection and 217,895 matched controls were identified in VHA data between January 1, 2001, and December 31, 2014, and followed until December 31, 2019.
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