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Volume 29, Number 10—October 2023
Research

Emergence of SARS-CoV-2 Delta Variant and Effect of Nonpharmaceutical Interventions, British Columbia, Canada

Y.L. Elaine ChanComments to Author , Michael A. Irvine, Natalie Prystajecky, Hind Sbihi, Marsha Taylor, Yayuk Joffres, Andrea Schertzer, Caren Rose, Louise Dyson, Edward M. Hill, Michael Tildesley, John R. Tyson, Linda M.N. Hoang, and Eleni Galanis
Author affiliations: British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada (Y.L.E. Chan, M.A. Irvine, N. Prystajecky, H. Sbihi, M. Taylor, Y. Joffres, A. Schertzer, C. Rose, J.R. Tyson, L.M.N. Hoang, E. Galanis); Public Health Agency of Canada, Ottawa, Ontario, Canada (Y.L.E. Chan, A. Schertzer); Simon Fraser University, Burnaby, British Columbia, Canada (M.A. Irvine); University of British Columbia, Vancouver (N. Prystajecky, H. Sbihi, C. Rose, L.M.N. Hoang, E. Galanis); University of Warwick, Coventry, UK (L. Dyson, E.M. Hill, M. Tildesley); Joint UNIversities Pandemic and Epidemiological Research (L. Dyson, E.M. Hill, M. Tildesley)

Main Article

Table 1

Pangolin lineage and patient demographics, vaccination status, and travel history for 1,178 SARS-CoV-2 Delta variant of concern cases reported in British Columbia, Canada, March 1–June 30, 2021

Characteristic No. (%) Delta cases
Pangolin lineage*
B.1.617.2 1,018 (86.4)
AY.18 44 (3.7)
AY.15 30 (2.5)
AY.10 22 (1.9)
AY.93 20 (1.7)
Other AY lineages
 44 (3.7)
Patient demographics
Age group, y
<20 261 (22.2)
20–39 513 (43.5)
40–59 248 (21.1)
60–79 118 (10.0)
>80 38 (3.2)
Sex
F 553 (46.9)
M 622 (52.8)
Unknown 3 (0.3)
Vaccination status†
Fully vaccinated 30 (2.5)
Partially vaccinated 168 (14.3)
Unvaccinated 980 (83.2)
Travel history
International travel 153 (13.0)
Domestic travel outside BC 14 (1.2)
No known travel or only within BC 1011 (85.8)

*Pangolin version 4.0.5, Usher version 1.6, Pango version 1.6 (20). BC, British Columbia. †Unadjusted proportions; vaccination status shown was at time of symptom onset or specimen collection. Patients were considered fully vaccinated if symptom onset (or positive specimen collection date if onset not available) occurred >14 d after second dose of BNT162b2 (Pfizer, https://www.pfizer.com), mRNA-1273 (Moderna, https://www.modernatx.com), or ChAdOx1 (AstraZeneca, https://www.astrazeneca.com). Patients were considered partially vaccinated if not fully vaccinated and onset/specimen collection date occurred >21 d after first dose. Persons without any recorded vaccine dose or with onset/specimen collection date <21 d after first dose were considered unvaccinated.

Main Article

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Page created: August 07, 2023
Page updated: September 20, 2023
Page reviewed: September 20, 2023
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