Risk of COVID-19 Infection After Vaccination

Risk of COVID-19 Infection After Vaccination: A Nationwide Study Comparing BNT162b2, mRNA-1273 and ChAdOx1

Status

UNKNOWN

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT04848441

Enrollment

2000000

Registered

2021-04-19

Start date

2021-05-01

Completion date

2021-08-01

Last updated

2021-04-19

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Covid19, Vaccination; Infection

Keywords

COVID-19, Vaccination, Nationwide observational study

Brief summary

The purpose of this observational nationwide study is to evaluate the effects of three different COVID-19 vaccines for the outcome of different severities of incident COVID infection.

Interventions

OTHERThe COVID-19 vaccines BNT162b2, mRNA-1273 and ChAdOx1

The purpose of the study is to compare the effects of BNT162b2, mRNA-1273 and ChAdOx1 with respect to incident COVID-19 infection of different severities.

Study design

Observational model

COHORT

Time perspective

RETROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

0 Years to 110 Years

Healthy volunteers

Inclusion criteria

* Living in Sweden and vaccinated with BNT162b2, mRNA-1273 or ChAdOx1 * All individuals with a previous COVID-19 infection * Controls matched 1:1 to the groups above

Exclusion criteria

* None

Design outcomes

Primary

Measure	Time frame	Description
Incident COVID-19 infection	Up to six months after vaccination	Four different severities: Being diagnosed, hospitalized, ICU-care and death within 30 days of diagnosis

Contacts

Primary ContactPeter Nordström, Prof

peter.nordstrom@umu.se+46907851000

Backup ContactMarcel Ballin, PhD

marcel.ballin@umu.se

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026