An illustration describing the research on roundworm infections by Nobel Medicine Prize winners 2015 is displayed on a screen during a press conference of the Nobel Committee to announce the winners of the 2015 Nobel Medicine Prize on October 5, 2015 at the Karolinska Institutet in Stockholm, Sweden. Irish-born William Campbell, Satoshi Omura of Japan and China's Youyou Tu won the Nobel Medicine Prize for their discoveries of treatments against parasites, the jury said. AFP PHOTO / JONATHAN NACKSTRAND (Photo credit should read JONATHAN NACKSTRAND/AFP/Getty Images)
