Study registration: *
Publication Flacco M, Vaccines, 2021
Dates: 2021-01-02 to 2021-05-21
Funding: No specific funding (no external funding)
Conflict of interest: no COI (The authors declare no conflict of interest.)

Methods

Study design:Cohort
Description of participants: Adults aged 18 and up without previous SARS-CoV-2 infection residing in Pescara, Italy
Inclusion criteria:
  • Aged ≥18 years
  • resident in the province of Pescara, Italy on 1 January 2021
  • assessed between January 17-May 21, 2021.

Exclusion criteria:
  • Previous SARS-CoV-2 infection or disease before start of follow up.

Follow-up duration (months): 4.65
Vaccines:
  • 1 or 2 doses of BNT162b2, 21 days apart
  • 1 or 2 doses of mRNA-1273
  • 1 or 2 doses of ChAdOx1-S
  • 1 or 2 doses of BNT162b2 or mRNA-1273 or ChAdOx1-S
Variant description :
Variant name: Alpha
Evidence: Indirect evidence (prevalence of variant in the population: 82.8% )
Documents
available

Protocol

NR

Statistical plan

No

Data-sharing stated: Yes
Data accessibility: The data presented in this study are available upon reasonable request from the corresponding author. Correspondence: lmanzoli@post.harvard.edu

General comment The published report was used in data extraction and risk of bias assessment. Of the vaccinated subjects, 52.8% received only one dose within the follow-up; 68.5% received BNT162b2 vaccine; 24.4% ChAdOx1 nCoV-19, and 7.0% mRNA-1273. Among those who received the second dose, 93.8% were vaccinated with BNT162b2, only 0.1% (n = 18) with ChAdOx1 nCoV-19, and the remaining 6.1% received mRNA-1273.
Concerns about uncontrolled confounding, a possiblity of selection bias for infection status after two doses, lack of information about missing data and possible bias in assessment of infection status.