Can I eliminate the option to reblog my posts?

I received a notification today that someone had reblogged a post from a photo blog I share with another friend. When I followed the link to the site (https://iloveusablog.wordpress.com/2013/07/28/friday-july-fifth-two-thousand-thirteen/), though, they had simply reblogged our post and added a spam comment to it. A quick look revealed that their whole blog consisted of posts like that (reblogs from other blogs, with the exact same spam comment added).

So basically, my post and photos were being used as the vehicle for spam. I don’t want my content used that way, but I’ve looked all over and can’t find an option to remove my content from their site (which now links back to mine) or an option to block future reblogs from that site in particular. Is there an option for this that I’m simply not seeing?