A report from the U.S. Center for Disease Control and Prevention showed young adults who were previously healthy can take a long time to recover from COVID-19.

According to the study, one in five adults ages 18 to 34 who had milder outpatient COVID-19 symptoms had not returned to their usual health after 14-21 days.

During the study, CDC officials conducted telephone interviews with a random sample of adults 18-years and older who tested positive for COVID-19 at one of 14 U.S. academic health care systems in 13 states. The interviews took place 14-21 days after the test day,

Interviewees were asked about their demographic characteristics, medical history, symptoms present at the time of testing and whether the symptoms had resolved.

Among the 292 respondents, nearly 94 percent reported they had experienced one or more symptoms at the time of testing, 35 percent of the symptomatic respondents reported not having returned to their usual health by the date of the interview.

The respondents reported having a cough, fatigue or shortness of breath at the time of testing.

CDC officials said the virus can result in prolonged illness, even among young adults with no underlying medical conditions. Officials said public health messaging targeted at young adults is important.

To read the full report, click here.