The total number of COVID-19 cases in the United States is unknown. But indications are that after months of decline, COVID-19 cases began to rise again in the late summer. The Centers for Disease Control and Prevention (CDC) reported 12,613 hospitalizations nationwide from COVID-19 in the week of Aug. 6 to 12. That was a 21.6% increase from the previous week. COVID-19 deaths rose 8.3% from the previous week. Hospitalizations and deaths have not reached the levels of the previous two winters, or even of spring 2023, Dr. Snyder says. But it’s important to note that COVID-19, unlike most respiratory viruses, is still circulating widely this summer. “We don’t see surges or upticks of most respiratory viruses in mid-August,” Dr. Snyder says. “So, COVID-19 is still something that’s a little different that our immune systems and the viruses have not come to homeostasis on. It has not yet settled in as a seasonal respiratory virus.” There are several different variants and subvariants of the coronavirus circulating throughout the U.S., Dr. Snyder says. None had emerged as the dominant variant as of late August.