Discrete Typing Units (DTUs)
It was found that in disease due to Trypanosoma cruzi infections many variations occur. They are claimed to be included by several so-called discrete typing units (DTUs). There exist apparently six different DTUs, which differ in their geographical distribution, ecological niches, vectors, and reservoir hosts as well in the severity of induced clinical symptoms. Each DTU is apparently based on a variety of strains of the parasites.