Scientists are on the verge of killing off a parasite (Dracunculus medinensis) that had plagued the human race since ancient times. Cases of Guinea worm disease have fallen by 99 per cent from 3.5million cases in 1986 to 1,060 in 2011. The disease has affected the poorest communities in Africa and is now found in just South Sudan, Mali, Ethiopia, and Chad.
The guinea worm makes his home in the fat layer of the human skin and sometimes pokes through it to lay eggs. The well known medical symbol - the "staff of Aesculap" - is representing the former practice to remove the worm slowly using a little stick to wrap the worm around without breaking it in order to avoid infection if a part of the worm is left inside the body.