Suffering at school

I have contamination OCD, school is a mental and physical torture. I recently just started high school (at Canada its secondary and starts at 11-12). Every single thing is contaminated. Plus there are so many disgusting people. Having to sit at a desk I dont even know who sat there makes me super anxious, eventually leading in everything at school is contaminated and when I get back I have to be super careful that the contamination doesn't get out. Ive experienced this in 6th grade... I don't wanna do it again for the next 5 years. I wanna drop out of school or run away.