"We are emerging from one of the darkest years in our nation's history into a summer of hope and joy, hopefully," declared President Joe Biden at a press conference on July 6, 2021. "We're closer than ever to declaring our independence from this deadly virus." The cause for his optimism was the fact that more than 182 million Americans had received at least one shot of the new COVID-19 vaccines, including nearly 90 percent of seniors and 70 percent of adults over the age of 27.
That 70 percent figure was significant because early in the pandemic many epidemiologists had suggested that was immunological threshold at which a population might achieve herd immunity. Herd immunity occurs when a sufficiently large portion of a population is immune to a disease either via vaccination or infection, making it difficult for the disease to continue to spread.
Biden did cautiously note the emergence of the new more highly infectious Delta variant of the coronavirus but asserted that "the good news is that our vaccinations are highly effective." He added, "If you're vaccinated, you're protected."
