Megan Romano, a senior-to-be at Northeast High, hoped to swim in six events at the Olympic Trials in three weeks.
Those plans, however, are in jeopardy after she came down with mononucleosis.
"This is a major obstacle," said St. Petersburg Aquatics coach Fred Lewis, who trains Romano.
Last week, Romano said she had a sore throat but decided to swim at a meet in Charlotte, N.C. After setting a personal-best in the 200 meter freestyle, she skipped the rest of her events due to fatigue.
On Monday, she went to the hospital, where tests revealed she has mononucleosis.
"I just felt really tired and beat," Romano said. "Doctors said I've probably had it for three or more weeks."
Nevertheless, Romano plans to compete at the swimming trials, which start June 29 in Omaha, Neb.
"It's something I definitely want to try," Romano said. "I just have to make sure not to push anything too hard."
Lewis said he will scale back workouts from four hours to 40 minutes the next three weeks.
"We're not going to let her go all out," Lewis said. "It's a hard break, but she still thinks she can give it a shot."