The Nobel prize for medicine or physiology has been awarded to three scientists – two French and one German - for their discoveries of two viruses that cause severe human diseases.
The prize of 10 million Swedish crowns (€1 million) was awarded to Harald zur Hausen of Germany for his work into the cause of cervical cancer and Francoise Barre-Sinoussi and Luc Montagnier of France for their discovery of the virus that causes Aids, Sweden's Karolinska Institute said.
Medicine is traditionally the first of the Nobel prizes awarded each year.
The prizes for achievement in science, literature and peace were first awarded in 1901 accordance with the will of dynamite inventor and businessman Alfred Nobel.
The Nobel peace prize will be awarded on Friday, a day after the winner of the literature award is announced.