What type of mites would chickens carry that would bite a human? Would they infest anything else in a barn?

I am having a problem with bites that are similar to chigger bites in my horse barn. This summer I added 2 chickens that run around. Everyone that seems to go to the barn gets bit, but it isn't the normal places chiggers bite. The barn is cinder-block and brick hallway. I actually got bit yesterday where the strap of my riding helmet fit and even on my forehead from my riding helmet. Help.