This disclosure describes, in one aspect, a composition that includes a transgenic pathogen that expresses a heterologous pathogen associated molecular pattern (PAMP). In some embodiments, the pathogen may be attenuated. In some embodiments, the pathogen can include T. cruzi. In another aspect, this disclosure describes a method of treating an infection in a subject. Generally, the method includes administering to the subject, in an amount effective to treat the infection, a pathogen genetically modified to express a pathogen-associated molecular pattern (PAMP) not natively expressed by the pathogen.
