"Although we're very positive about the vaccine, it is absolutely imperative that we continue our work to wear masks, to avoid crowded spaces, to physically distance, to avoid travel if you can," he said. "Because until the vaccine gets widespread, this is still our best measures to flatten the curve and save lives."
While urging people to observe these safety measures and listed to public health messages, he emphasized that the US is "still at a dangerous and critical part of this pandemic and tens of thousands of American lives are at stake."
The current vaccine rollout will create an impact on the number of new Covid-19 cases, hospitalizations and deaths in the US. This will be seen "almost immediately," Giroir said, but cautioned that widespread immunity through vaccination will not come until the late spring or early summer.
Meanwhile, the White House testing czar is hoping to increase testing availability in the country.
"You're going to hear more good news from the FDA very soon about other home tests that are not exactly the over-the-counter type, but are in the same ballpark," he said. "You'll see more and more tests get authorized, and them ramping up very soon, in the early part of the year."