I think it depends on whether there was harm done or not.
If the girl had any communicable disease, then yes.
If the girl was healthy, then it’s a really stupid prank that could have done real harm and probation and community serviced is in order.
I'm thinking it should be serious punishment since so many are doing the same thing. A lenient sentence would be 2 years.
What if she licks a tongue depressor of someone who’s immune system is compromised? Even a small bug could threaten their life.