For a fleeting moment this summer, it seemed like things were approaching normal. Vaccinated people got the green light to safely resume activities that were off-limits for over a year. Companies laid out plans for returning to the office. People ditched their masks.

But in a disturbing case of pandemic déjà vu, the seven-day average number of Covid cases topped 100,000 on Sunday. That's the highest it's been since February, fueled by the virus's more transmissible delta variant.