It was a miserable five days. My legs and arms ached, my fever crept up to 103 and every few hours of sleep would leave my sheets drenched in sweat. I’d drop into bed exhausted after a quick trip down to the kitchen. To sum it up, I’d put my breakthrough case of COVID-19 right up there with my worst bouts of flu. Even after my fever cleared up, I spent the next few weeks feeling low.

Of course, I am very lucky. I didn’t go up against the virus with a naive immune system, like millions of Americans did until vaccines were widely available. And, in much of the world, vaccines are still a distant promise.

“You probably would have gotten much sicker if you had not been vaccinated,” Dr. Francesca Torriani, an infectious disease physician at the University of California, San Diego, explained to me recently.

As I shuffled around my room checking my fever, it was also reassuring to know that my chances of ending up in the hospital were very slim, even with the delta variant. And now, about a month later, I’ve made a full recovery.