Should I wear a mask when I work in health care facilities after COVID-19 vaccination? Will I have protective immune response? Will my nucleic acid testing turn positive for COVID-19? Discussion in the context of herd immunity. CoronavirusCOVID-19COVID-19 immunityCOVID19Herdimmune systemIMMUNITYMASKVaccinationvideoVITAMINvlogWearYouTube