Dr. Fauci warns of 'more ominous' strains of COVID-19 from Brazil and South Africa

US top infectious disease expert warns of 'more ominous' COVID-19 mutations Dr. Anthony Fauci said health officials are 'looking at them very carefully' New strains from Brazil and South Africa are considered more contagious But it is not known if the new variants will less impact of COVID-19 vaccine Fauci said US is 'weeks away' from approving two new COVID-19 vaccinations Johnson & Johnson and AstraZeneca are getting set to roll out new inoculation Fauci also inoculating 100 million Americans in Biden's first 100 days is 'doable'