Call your vet and ask them. Yes it is high contagious.

Crystal had it as a kitten when she arrived here. I remember we got special shampoo from the vet and had to wash the area 3 times daily for 2 weeks. The shampoo had to sit in place for 3 minutes, I would set the kitchen timer and Dad would walk around holding her, wrapped in a towel. It was a spot on her head, forehead (if cats have such a thing!) so it was hard to keep it out of her eyes, which was important too.