[The assessment process within science and the nomination of Carlos Chagas for the Nobel prize for Physiology or Medicine].

One of the greatest achievements in the history of medicine was the description of Chagas disease by the physician and scientist Carlos Chagas. A hundred years after the discovery of the disease, speculation still remains regarding the two official nominations of Carlos Chagas for the Nobel Prize, the biggest worldwide scientific award, in 1913 and in 1921. It has been accepted that the reason why the prize was not awarded to this brilliant scientist may have been the strong opposition that he faced in Brazil, from some physicians and researchers of that time. They went as far as questioning the existence of Chagas disease, thereby possibly influencing the decision of the Nobel Committee not to award the prize to him. Analysis of the database of the Nobel prize archives, with the revelation of the names of nominators, nominees and prizewinners spanning the years 1901-1951, brought information not only about what was considered to be a scientific achievement at that time, but also about who the important scientists were and what the relationships between them were. The non-recognition of Carlos Chagas' discoveries by the Nobel Committee appears to be more correctly explained by these factors than by the negative impact of the local opposition.