Study registration: *
Publication Nunes B, medRxiv, 2021
Dates: 2021-03-30 to 2021-08-11
Funding: No specific funding (No funding is declared)
Conflict of interest: no COI (The authors have declared no competing interest.)

Methods

Study design:Cohort
Description of participants: Older adults aged 65 to 79 without previous SARS-CoV-2 infection living in the community in mainland Portugal
Inclusion criteria:
  • Individuals aged 65-79 years old
  • resident in private households in Portugal mainland
  • eligible for vaccination
  • National Health Service frequent users

Exclusion criteria:
  • Institutionalized
  • residents in autonomous regions of Madeira and Azores
  • previous SARS-CoV-2 infection
  • receipt of a non-mRNA vaccine against SARS-CoV-2 (but included until vaccination).

Follow-up duration (months): 4.47
Vaccines:
  • 2 doses of either BNT162b2 or mRNA-1273
Variant description :
Variant name: Delta
Evidence: Indirect evidence (prevalence of variant in the population: 1 to 99%)
Documents
available

Protocol

NR

Statistical plan

NR

Data-sharing stated: No
Data accessibility: NR
General comment Concerns over uncontrolled confounding, particularly due to having COVID-19 symptoms at the time of planned vaccination.