SAN FRANCISCO (KGO) -- As coronavirus cases continue creeping up across the country and in the Bay Area, health experts warn new data shows young children and teens are contributing to the spike in transmission.
It's a concerning trend as kids under five aren't yet eligible to be vaccinated.
Children now make up one in every five new COVID cases, according to data from the Centers for Disease Control and Prevention. In recent weeks, kids have made up roughly a quarter of all new COVID cases across the country.
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"The disease is finally getting into pediatric populations," said UCSF's Dr. George Rutherford, a pediatrician and epidemiologist.
Since the beginning of the pandemic, more than 7 million children and adolescents have tested positive for COVID-19, according to the American Academy of Pediatrics. Both age groups were not seen as super spreaders early in the pandemic, but new data shows that's starting to change.
CDC data shows children under 18 now represent the largest per capita increase in new cases since the summer. But Rutherford says that's due to the pediatric population reporting such a low number of cases prior to the Delta surge.
"It's now being diagnosed in greater numbers in children and part of that is because we have extensive screening programs in schools that are picking up asymptomatic cases," said Rutherford.
More than 1,500 children are currently hospitalized with COVID - a 37 percent increase over the past week, according to the CDC. Rutherford says those cases stem from Delta which is known to cause severe disease, whereas there's little known about omicron's impact on kids.
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This brings us to these burning questions -- should you change your holiday plans? What are the risk factors?
"It depends on how old the kids are," said Rutherford. "I mean if they are two weeks old, no. These are relative things. If it's a 17-year-old who hangs around all his friends who aren't vaccinated, then yeah there's some real risk to that."
Stanford Infectious Disease Physician Dr. Jorge Salinas says the only way to safely gather in large groups is to ensure anyone eligible is vaccinated and boosted or gets tested beforehand. He says depending on how people adhere to these recommendations will determine the severity of future surges.
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"I'm somewhat optimistic about the fact that a surge or a winter surge may be different this time compared to last year," said Salinas. "Most of our community has been vaccinated with some level of immunity."
But, what about those under 5 -- not yet eligible or protected?
Rutherford says for that age group it comes down to checking their symptoms to monitor any signs of illness, notably fever and cough.
"In this part of California, we have relatively lower risk of disease and we really haven't seen much in nursery schools, so I wouldn't worry about them so much," he said.
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According to Rutherford, elementary school-aged children should be vaccinated by now, but says to be careful if they aren't and will be attending family gatherings. Same is true with unvaccinated adolescents, as the risk of transmission is just as high as seen with adults.
Experts also recommend getting tested 24 hours before attending a large family gathering.