By CBSBoston.com Staff

(CBS/CNN) — The Centers For Disease Control is urging parents to vaccinate their teens after an increase in coronavirus hospitalizations among kids ages 12 to 17.  A CDC study released Friday detailed “troubling” recent data around Covid-19 hospitalizations among adolescents, and urged continued use of prevention measures.

The study showed that nearly one-third of teenagers hospitalized with COVID earlier this year required intensive care, and 5% were put on ventilators.

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During a White House Covid-19 briefing on Thursday, CDC Director Dr. Rochelle Walensky noted that in the month before the Pfizer vaccine was authorized for people as young as 12, the agency observed “troubling data” about adolescents hospitalized with severe Covid-19.

The data found that after initially decreasing in early 2021, adolescent hospitalization rates for Covid-19 increased during March to April. The increase may have been related to more transmissible coronavirus variants, large numbers of children returning to school and other indoor activities and changes in prevention behaviors, researchers wrote.

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The study looked at the period before a vaccine was authorized for people as young as 12 in May.

“More concerning,” Walensky said, were the number of adolescents admitted to the hospital who required treatment in the intensive care unit with mechanical ventilation: Among 204 adolescents hospitalized primarily for Covid-19 during January 1 to March 31, 2021, 31.4% were admitted to an intensive care unit and 4.9% required invasive mechanical ventilation. There were no associated deaths, the new study said.

“It is these findings within this publication — one that demonstrates the level of severe disease, even among youth, that are preventable — that force us to redouble our motivation to get our adolescents and young adults vaccinated,” Walensky said Thursday.

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(© Copyright 2021 CBS Broadcasting Inc. All Rights Reserved. CNN’s Jen Christensen contributed to this report.)

CBSBoston.com Staff