Carlos Chagas is considered to be one of the most brilliant Brazilian scientists of all time. The accomplishment of this scientist was to discover the etiologic agent, the vector insect, reservoir animals and the disease. This seems to be unique in medical history. Therefore, it is no surprise that Chagas was twice nominated for the Nobel Prize, each time (1913 and 1921) by a single Brazilian nominator. Based on information of Sierra Iglesias (1990), Brazilian researchers support the idea that Chagas was not awarded the Nobel Prize due to criticism made by his colleagues of the National Academy of Medicine. However, based on data recently released by the Nobel Foundation, this idea is being challenged. We suggest that a better explanation for this not awarded prize can be found in the relationships of credibility and respect between researchers of the central countries and those of the peripheric ones