This mirrors what is reported by @UKHSA. Vaccine protection against severe outcomes began declining faster with BQ.1 and XBB.1.5 variants than with previous variants. This also helps explain increasing excess mortality in Canada over fall/winter. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1149407/vaccine-surveillance-report-2023-week-14.pdf
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