You should treat the person who bit you like an animal. They have to be alive to be tested so set a trap to capture them, then take them to a doctor for testing. It'd be easier if you hit them over the head with a 2x4 so they'd be unconscious. Dr. Crank is actually a lawyer, so I'd recommend seeing your doctor asap to document the injury, report it to the police, then sue the person with the biting problem.