How do you stop your kids from itching mosquito bites?

My son has really bad mosquito bites on his legs. He has has been itching them so bad that it’s starting to look like it will scar. He gets really bad reactions to mosquitos where the bites get like as big as nickels, what do you guys do to stop your kids from itching? He’s only one so he doesn’t really understand when I tell him to itch around it