And the 27-year-old forward hopes the league will take into account players with pre-existing conditions when pondering plans to restart the season halted March 12 by the deadly disease.
"I would hope there would be an understanding (by the NBA) if someone didn't feel comfortable coming back, that you would get a pass," Nance told ESPN. "Just because you may look like the picture of health, some people have issues you can't see."
Nance, who spent his first 2 1/2 NBA seasons with the Los Angeles Lakers before being traded to Cleveland in 2018, is among those who conducted individual workouts at the Cavaliers training facility the past two weeks.
His therapy to combat inflammatory bowel illness allows Nance to play but weakens his immune system and leaves him more vulnerable than most to catch COVID-19.
Nance said he was "absolutely terrified" when Utah's Rudy Gobert tested positive for the coronavirus -- leading to the NBA shutdown -- because he had recently played against the Frenchman.
"We're young and you know the kind of shape players are in, you'd like to think (the virus impact) wouldn't be what it could be for others," Nance said.
"But you don't know. I'm still scared and don't want to get it."
Nance told ESPN a drug he has taken for 10 years to combat Crohn's has helped those with the disease fight off COVID-19, easing some of his worries with hopes he could join his teammates on the court if the season resumes.
The Cavaliers were 19-46, worst in the Eastern Conference and second-worst in the NBA ahead of only Golden State, when the league went on hiatus.
Nance, averaging 10.1 points and 7.3 rebounds when the season was halted, was a very interested spectator last weekend when the Bundesliga made its return in empty German stadiums.
"I'm paying super close attention to everything that is going on," Nance said. "I was watching the German soccer league over the weekend and seeing how the players were interacting with each other and still seeing them make a lot of contact."