Total COVID-19 hospital admissions jumped by 12.1 percent in the past week, according to the most recent data from the Centers for Disease Control and Prevention (CDC), marking the highest jump in admissions since last winter.

This week’s hospital admission rate follows last week’s rise of more than 10 percent. While this data suggests more infections, a metric the CDC does not track anymore, it remains unclear how concerned people should be.

While hospital admissions have risen by more than 10 percent in each of the past two weeks, the number of patients currently hospitalized has risen by a comparatively smaller degree. Compared with last week, the number of patients hospitalized for COVID this week rose by 7 percent to 6,121. Deaths due to COVID-19 have also not changed in recent weeks as hospital admissions have risen.

The most recent wastewater surveillance data from July found that the majority of sites in the U.S. are seeing lower levels of the COVID-19 virus. Only 7 percent of sites are reporting levels between 60 and 100 percent, encompassing the two highest categories of viral wastewater detection. The number of sites reporting data has been declining since June, but the majority are still providing information.

It has been almost three months since the public health emergency for COVID-19 expired and life has largely returned to pre-pandemic rhythms for the majority of people. After three years of living with COVID-19, a small surge in cases during the summer may be a new norm to get used to.

“We have had a summer wave of COVID for the last few summers and so it’s not surprising to see an increase in COVID right now,” Jill Rosenthal, director of public health policy at the Center for American Progress, told The Hill.

A smaller summer wave of COVID cases has been observed each year since the very start of the outbreak. Coronavirus cases began to climb in mid-June of 2020 after having previously plateaued for a few weeks. A larger surge began around July 2021, and cases remained elevated throughout May and August of last year.

Many people rightly associate increases in respiratory viral infections to colder weather, when people are driven indoors and transmission more easily occurs in smaller spaces with less air flow. But the warmer weather comes with its own factors that encourage behaviors that could lead to more infections.

Just as colder weather drives people indoors, warmer weather invites people to go outside, let their guards down and gather together. This urge to be outside is perhaps even stronger with the official end of the public health emergency.

The summer also sees higher rates of travel, which may be spreading viruses like COVID faster than they normally would. A survey from Forbes found that half of consumers said they planned to travel more in 2023, and 45 percent said they were budgeting to spend more on travel this year.

And while people may be spending more time outdoors, Rosenthal noted that extreme heat also drives vulnerable populations, such as homeless people, to public indoor cooling centers where crowding could be worse and infections spread more easily.

Speaking on heat waves and COVID, Rosenthal said, “There’s an indirect link between the two.”

She noted that some people also believe in the myth that ambient heat and sunlight can eradicate the coronavirus, leading them to be less cautious in public. While UVC rays have been found to help reduce microbes in the air, the American Academy of Dermatology has previously pointed out that the atmosphere blocks those rays from reaching the Earth’s surface.

At the same time as hospital admissions are rising, officials are working on efforts to prevent a major surge later in the year.

Federal health authorities are currently preparing for a fall vaccine campaign this year, the first that will mimic a normal flu shot campaign. Both Moderna and Pfizer have filed for FDA authorization of their respective shots updated to protect against the XBB.1.5 Omicron subvariant.