Yes, getting 70 percent of all Americans vaccinated is a worthy goal. But what matters even more is that enough people in enough places are vaccinated.

Photo: Baltimore County government

For months, a tantalizing number has driven America’s Covid-19 response. First, it was 60 to 70 percent; then, as the virus blanketed the globe and evolved to become more contagious, it rose to 75 or even 85 percent.

Herd immunity, which occurs when enough people become immune to a virus that new cases don’t take off and cause outbreaks, has been a major goal in the United States since the pandemic began. Exactly what percentage is needed in the case of SARS-CoV-2, the virus that causes Covid-19, is unclear, but the latest estimate is at least 70 percent. And the key to reaching it, experts say, is paradoxical: Don’t focus on it too hard. Read more at The New Republic.