Effectiveness of Face Mask or Respirator Use in Indoor Public Settings for Prevention of SARS-CoV-2 Infection - California, February-December 2021

摘要

This report describes face mask or respirator effectiveness in helping protect against COVID-19 infection.

This report describes face mask or respirator effectiveness in helping protect against COVID-19 infection.

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萃取時間: 2026-02-05T15:12:50Z 資料來源: CDC MMWR