Omicron BA.1/1.1 SARS-CoV-2 Infection among Vaccinated Canadian Adults

The incidence of the omicron BA.1/1.1 variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which rapidly spread worldwide even among vaccinated persons, is incompletely defined.1 We quantified the incidence of SARS-CoV-2 infection during the initial omicron BA.1/1.1 variant wave among Canadian adults2 and the contribution of previous infection and concurrent vaccination to age specific active immunity.

Read the full paper here (The NEW ENGLAND JOURNAL of MEDICINE) or (Download PDF)

Patrick E. Brown, Ph.D.
Sze Hang Fu, M.S.A.
Aiyush Bansal, M.D.
Leslie Newcombe, B.Sc.
Unity Health Toronto, Toronto, ON, Canada

Karen Colwill, Ph.D.
Geneviève Mailhot, M.Sc.
Melanie Delgado-Brand, B.Sc.
Anne-Claude Gingras, Ph.D.
Sinai Health, Toronto, ON, Canada

Arthur S. Slutsky, M.D.
Maria Pasic, Ph.D.
Jeffrey Companion, M.L.T.
Unity Health Toronto, Toronto, ON, Canada

Isaac I. Bogoch, M.D.
Toronto General Hospital, Toronto, ON, Canada

Ed Morawski, M.A.
Teresa Lam, B.A.
Angus Reid, Ph.D.
Angus Reid Institute, Vancouver, BC, Canada

Prabhat Jha, M.D., D.Phil.
Unity Health Toronto, Toronto, ON, Canada

for the Ab-C Study Collaborators