Wife has covid still mild symptoms day 7 since test. sudden numb tongue on both sides. compares it to local anesthesia shot during dental work. no stroke symptoms otherwise. causes? emergency? covid related?

This symptom may be related to the infection. I would recommend a neurologic exam at acute care today. If there is associated loss of taste or smell, this is a relatively common association with the infection. The sudden nature of the onset is of concern, please see acute care today. COVID 19 may be associated with embolic complications. Watch for signs of shortness of breath, chest pain and fever

Important that she be under a Physician's care. Perhaps both specialists in Infectious Diseases and Neurology. Cannot diagnose without full history, intensive physical examination, appropriate lab tests, and perhaps imaging. Hopefully she's fully vaccinated. There are anti-virals available. she should see her GP or Acute Care immediately.