(COLORADO) — Colorado is reporting that 26 percent of its new COVID-19 cases are coming from children. 

Health officials found that, as of this week, one out of every four new coronavirus cases is a person under 19-years-old. 

Dr. Sean O’Leary, a pediatrician and professor at the University of Colorado School of Medicine, believes the more-contagious variants coupled with the resuming of outdoor sports and loosened COVID-19 restrictions caused the spike in new cases among children and young adults.

In addition, “Kids under 16 right now are not eligible for vaccination so that’s a group that is completely prone to getting infected at this point,” O’Leary tells ABC News.

Colorado has reported four variants among its new cases, including the more infectious B.1.1.7 variant, which was first discovered in the United Kingdom.

The state reported 210 active outbreaks in area schools — which is the highest number since the December 2 peak, at 211 active outbreaks.  

“Kids have been a little bit more out there, there’s been some outbreaks in schools. There’s lots of after-school activities happening as well, we’ve seen some outbreaks in sports,” said O’Leary. “Who is getting infected in schools has also shifted. More infections are happening in students as opposed to the staff.”

O’Leary also noted hospitalizations among children are up in Colorado, with 847 hospitalizations and 13 deaths since the start of the pandemic.

Colorado’s case is not exclusive — the number of national child infections is going up with young adults now making up 22 percent of recent COVID-19 cases.

 72,000 new child virus cases were reported between April 22 to April 29, reports the American Academy of Pediatrics and the Children’s Hospital Association.  The number is four percent higher than two weeks ago.

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