Jan. 13 (UPI) -- Adults between 18 and 24 years old account for nearly 60% of new COVID-19 cases among young people, according to data released Wednesday by the U.S. Centers for Disease Control and Prevention.
Young adults were involved in roughly 1.7 million of the nearly 2.9 million cases of the new coronavirus reported in people under age 24 between March 1 and Dec. 12 of last year, the data showed.
Of the documented cases in this age group, 96% experienced symptoms, agency researchers said.
Conversely, school-aged children, age 5 to 17 years, made up about 35% of all reported cases in people 24 years of age and younger, the data showed.
The percentage of positive COVID-19 tests among children, adolescents and young adults spiked in early summer and then, after a downturn, "steeply increased" between October and December after many schools and colleges reopened across the country, according to the CDC.
"Infection rates are generally going to be lower in children under 18, compared to younger adults over that age, because children are more likely going to be in environments with strict compliance with COVID-19 protocols," Dr. Danny Benjamin, a pediatric infectious disease expert, told UPI.
"They are at lower risk because most [elementary, middle and high] schools aren't playing around," said Benjamin, a professor of pediatrics at Duke University who was not part of the CDC analysis.
In an ongoing assessment of COVID-19 spread and compliance with protocols designed to limit transmission in primary and secondary schools, which includes 2 million schoolchildren in multiple states, Benjamin and his colleagues have reported limited cases of the virus in participating schools.
That's due in large part to the fact that students and staff at these schools comply with masking and social distancing protocols 99% of the time, Benjamin said.
However, this level of compliance has been seen at many, but not all, colleges and universities nationally, he said.
And, even if students and professors at these institutions wear masks and practice social distancing "in the classroom," students put themselves at risk by going into the surrounding community for work or to drink in bars, according to Benjamin.
"If you're not in an environment where people are taking [this virus] seriously, you're in trouble," he said.
As a result, younger adults saw higher rates of COVID-19 infections throughout the summer and fall, with peaks in mid-July and early September, when many returned to campus or work, the CDC data showed.
This suggests "that young adults might contribute more to community transmission than do younger children," the agency said.
"CDC continues to update guidance for all locations, including colleges and schools, as we learn more about COVID-19," co-author Erin Sauber-Schatz, a commander in the U.S. Public Health Service, told UPI.