Chagas disease; immunology; evolution; mathematical model; Similarity analysis

Chagas disease is a neglected tropical disease endemic to the American continent with Trypanosoma cruzi as its etiologic agent. This disease has a major impact on public health, affecting about 6 -8 million people around the world. Currently, there are limitations in its treatment and prevention, such as the lack of vaccines and widely effective drugs. The parasite typically presents a complex life cycle involving the triatomine insect vector and the mammalian host, in addition to other means of transmission such as oral and congenital. Chagas disease in its clinical course has two phases: the acute phase characterized by a strong immune response, reduction of parasitemia, but without the elimination of the infection leading to chronification and the chronic phase, predominantly asymptomatic in a smaller percentage, manifesting cardiac and/or gastrointestinal syndromes. years after infection. However, the causes that lead to the manifestation or not of symptoms of the chronic phase are not fully understood. We propose to investigate the dynamics and mechanisms underlying chronification. The Trypanosoma cruzi has virulence factors that help it evade the immune system and maintain it in the host. Considering the long process of molecular interaction as a selective pressure agent, we suggest that the efficiency of some of these virulence mechanisms, with those carried out by proteins of parasitic surface, is due to a certain similarity with human proteins due to a molecular evolutionary convergence. we search for evidence of this hypothesis; we carry out analyzes of similarity between Trypanosoma cruzi surface proteins and the immune system and human signal transduction. Also, the events that occurred during the acute phase seem to have a decisive impact on the later development of the disease, as in the definition of the host's state of resistance and susceptibility. We then present a mathematical model that proposes to investigate the scenarios in the parasite-system dynamics that end the states of susceptibility and resistance in infection by Trypanosoma cruzi. It simulates relevant characteristics of the dynamics of the acute phase of Chagas disease.