As of Nov. 25, there were 19,444 weekly COVID hospitalizations, CDC data shows.
For nearly a month, COVID-19 hospitalizations have been increasing following weeks of decline and relatively low levels throughout the summer, according to data from the Centers for Disease Control and Prevention (CDC).
As of Nov. 25, there were 19,444 weekly hospitalizations due to the virus compared to 15,006 four weeks earlier, data shows.
The video is from a previous report.
While this marks an increase of 29.6%, it is lower than the 150,650 weekly hospitalizations at the peak of the omicron wave during the 2021-22 season.
Rates of COVID hospitalizations remain elevated among senior citizens, middle-aged adults and children under age 4, meaning the virus is affecting both the oldest and youngest Americans.
"COVID has not disappeared, although it may have gone from many people's minds and the top of their attention," Dr. William Schaffner, a professor of preventive medicine at Vanderbilt University Medical Center, told ABC News. "I'm afraid the COVID virus is still very much with us."
He added, "These omicron variants and subvariants are highly contagious. They're causing lots of milder illness that does not require hospitalizations. However, there are substantial hospitalizations across the country."
Americans aged 65 and older have the highest rate of weekly hospitalizations of any age group in the U.S., as they have throughout the pandemic, at 13.5% per 100,000 for the week ending Dec. 2, CDC data shows.
Experts said there are multiple reasons for this age group to have high rates of hospitalizations, including age being a risk factor for severe disease and senior citizens having more chronic underlying medical conditions that raise the risk of severe disease.
Another reason is vaccine uptake and waning immunity. While 94.4% of adults aged 65 and older completed a primary series of the original vaccine, 33.3% of adults aged 65 and older have received the updated vaccine, according to CDC data.
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"Many people, although they have been vaccinated in the past, have not taken advantage of this updated vaccine," Schaffner said. "And the protection afforded by the previous vaccinations is now slowly declining. And so, we have a highly vulnerable population whose protection is slowly waning."
Those aged 50 to 64 have the second-highest rate of weekly hospitalizations by age group at 2.7% per 100,000. Experts said, similarly, this is a group that is starting to see the emergence of chronic underlying conditions that raise the risk of severe illness from COVID.
Dr. Peter Chin-Hong, a professor of medicine and an infectious diseases expert at the University of California, San Francisco, said another reason middle-aged and older Americans have higher rates of hospitalization is that the most vulnerable among this group are not receiving treatments like Paxlovid. Reports have suggested that in some states, it's prescribed in less that 25% of cases.
"It represents a failure of our system to intervene and provide early therapy," Chin-Hong. "You can't really just blame vaccinations because there's a get out of jail card, which is Paxlovid and even remdesivir."
While only those at risk of severe illness are recommended to take Paxlovid, Chin-Hong said it's been a relatively underused treatment because some may feel they don't need the drug or doctors may feel hesitant to prescribe it due to concerns about how the medication interacts with other prescription drugs.
There's also some confusion about who pays for Paxlovid, Chin-Hong said. While it has been and will continue to be free through 2024 for people with Medicare or Medicaid, people with private insurance may have co-pays associated with the drug now that it will no longer be purchased and distributed by the government.
Infants and young children under age 4 have the third-highest rate of hospitalizations by age group at 1.6% per 100,000 for the week ending Dec. 2, CDC data shows.
Although children are less likely to fall severely ill and die from COVID compared to adults, they can get sick enough to be hospitalized.
Schaffner said it's a fallacy for a parent to think their child does not need to get vaccinated because they are relatively healthy because children can fall severely ill. What's more, studies have shown that COVID vaccines do decrease hospitalizations among kids.
"It has been very difficult for people to keep two apparently conflicting notions in their mind at the same time," Schaffner said. "First, everyone knows that children are less apt to be seriously affected by COVID infections than older adults. The alternate concept that is hard for parents to grasp is that nonetheless, young children account for the third most common age group with hospitalizations."
Chin-Hong said that parents are less hesitant to get their children vaccinated against influenza than against COVID-19. As of Nov. 18, 38.2% of children aged 6 months to 17 years have gotten a flu shot, CDC data shows. Comparatively, 6.9% of children have gotten an updated COVID vaccine as of Nov. 25.
"More than double are getting flu shots," he said. "So, it's not that everybody's saying, 'No' to vaccines. They're being selective."
While COVID has not followed a traditional seasonal trend like flu, experts say that for all age groups, increases in hospitalizations have occurred during the colder months when people begin to stay indoors, heat is turned up, windows are closed, and holiday gatherings people bring people together -- "ideal conditions for respiratory viruses to spread," said Dr. John Brownstein, an epidemiologist and chief innovation officer at Boston Children's Hospital and an ABC News contributor.
"As people gather for the holidays, it's crucial to remain vigilant about COVID-19, especially in protecting vulnerable populations like the elderly and infants," Brownstein continued. "Practicing good hygiene, such as regular hand washing, and staying home if feeling unwell are key. Additionally, ensuring proper ventilation in indoor spaces and considering wearing masks in crowded settings can significantly reduce the risk of transmission."
The experts also advised the importance of staying up to date on COVID-19 vaccinations and said it's not too late to get a shot.
"Seriously, make a plan and do it as quickly as possible," Schaffner said. "Getting yourself vaccinated and making sure your family members are vaccinated, that's without a doubt -- and I mean, this sincerely -- the best present, you can give yourself and give to them this holiday season, and you will help also make your neighborhood and your community safer."