show Abstracthide AbstractWe tested 3400 febrile patients from Peru for hantaviruses, yielding 1 Rio Mamore virus (RIOMV) genetically related to a Peruvian RIOMV from 1996. IgM ELISA-based hantavirus incidence averaged over 2020 in Amazonian Peru was 1.6% and IgG ELISA/immunofluorescence-based seroprevalence in 3 Peruvian departments was 2.9%. Hantaviruses are underrecognized human pathogens