Sentence:  "I draw blood from patients, and then I take it back to the lab and analyze it. Sometimes, the <WSD>vampires</WSD> do all the sticks, that is to say the lab assistants do all the blood collections." He grinned. "We have our own language at the lab." 
Meaning of the word marked with <WSD> tags:  A medical technician who works with patients' blood.