Doctors were left stunned after a boy suffering breathing difficulties coughed up a blood-soaked live leech from his throat. Xiaoxiang, 7, also had a nasty cough and was coughing up blood in his ...

In this short film Dr Michael Mosley interviews a surgeon who is pioneering the use of leeches in medical research. He allows a leech to attach to his arm and suck his blood, the mouth of the ...