Dr. Edward Dominguez says new variants are more transmissible than the early strains causing the herd immunity threshold to rise closer to 80%. Coronaviruscoronavirus immunitycoronavirus vaccine updatecovid 19 vaccine newscovid 19 vaccine updateCOVID-19COVID19eradicateHerdherd immunityherd immunity coronavirusherd immunity covidherd immunity covid 19herd immunity explainedherd immunity without vaccineimmune systemIMMUNITYvaccine hesitancyverifyvideoVITAMINvlogwfaawfaa dallaswfaa news 8 dallasYouTube