When coming to work each day, your employees should be asked to self-report any virus-related symptoms if they have any (including fever, chills, cough, shortness of breath, difficulty breathing, or sore throat). During this self-report, you must be mindful of any pre-existing conditions that your employees have. If an employee reports having one or more of these symptoms, or if you observe them, then the CDC has recommended that the employee either stays home or that they are sent home from work.
As an employer, you must determine the amount of risk that you are willing to take on regarding sending employees home from work without pay or not. If you knowingly keep an employee at work who is presenting at least one symptom in order to prevent you from being short-staffed and then this employee infects multiple patients or other employees, you could be held responsible for others getting sick if you knowingly asked them to stay at work after they have self-reported symptoms to you. While being short-staffed for a day is not ideal, having to close down your office for weeks because multiple employees are sick, and the legal issues that will follow due to your negligence are much worse.