A summer covid wave has washed over most of the United States, bringing yet another round of gatherings turned into superspreaders, vacations foiled by illness and reminders that pandemic life has not been fully erased. Not even President Biden was spared.

Coronavirus activity in wastewater reached levels considered “high” or “very high” in 26 states, according to the most recent data reported by the Centers for Disease Control and Prevention. Other metrics also suggest the virus is rising, including the prevalence of covid diagnoses in emergency rooms and the rate of tests processed at labs coming back positive.

“Covid is not gone. Covid is going to be around, probably forever, and we are going to typically see two to three waves a year,” said Ashish Jha, the dean of the Brown University School of Public Health who stepped down last year as the White House coronavirus coordinator.

Medically vulnerable Americans are navigating another summer fraught with the risk of Covid. Covid has spiked every summer since the pandemic started, which experts attribute to increased travel, large gatherings such as weddings and conferences, the rise of new variants, and even the heat driving people inside where the virus spreads more easily.