A alert needs to be sent to an administrator regardless of whether or not the virus was cleaned up or not.
Don Sz commented
This is needed so that I can ask the user what they were doing near the time the virus was cleaned up. Asking them 4 hours later, when I notice that the virus was cleaned up really does no good.
Maybe not an alert but a Report like in old on prem where you could schedule a report so you would get a daily report of all Adware / PUA and Virus's