We captured 3 hantavirus rodent hosts in Otamendi Natural Reserve, Argentina, during 2007-2012. Hantavirus antibodies were found only in Akodon azarae grass mice, mainly in males and old animals. Higher abundance of this species was associated with warm and rainy weather and high water levels, which peaked after a strong El Niño event.
Keywords: Akodon azarae; Argentina; Otamendi Natural Reserve; antibody prevalence; climate; disease transmission; ecology; environmental factors; grass mouse; hantavirus; infection; logistic regression models; protected area; rodent abundance; rodents; viruses; weather; zoonoses.