How do you guys get people not to touch your babies?

Na

Today i had to go to work with my 4 month old and a coworker kept touching her face. I was baffled, fuming, and wanted to run away with my baby. How do you tell people off? I am not confrontational, but with this pandemic, people should bw smart. Luckily I washed her face as soon as i could but it still pisses me off.