Hantavirus in rodent populations of selected national parks in Argentina

GÓMEZ VILLAFAÑE, ISABEL; SAN MARTÍN, ALVARO; VADELL, MARÍA VICTORIA; EXPÓSITO, YANINA; BELLOMO, CARLA; PADULA, PAULA

Atenas

Conferencia; VIII International Conference on Hantaviruses; 2010

Objective: The aim of this study was to establish potential sectors of risk to hantavirus in areas where cases of HPS have already occurred by genotyping the circulating virus in communities of rodents that inhabit three protected areas of Argentina bordering the rivers Parana and Uruguay. Methods: Rodents were seasonally live-captured in El Palmar and Pre-Delta National Parks and in the Natural Reserve Otamendi for 2 years. Captured rodents were, identified, sexed, and measured. Whole blood was tested for antibody reactive with Andes virus (ANDV) antigen by ELISA and lungs from positive animals were used for viral identification. Results: Trap nights yielded 708 small mammals of 9 species from the 3 parks. Relative density of reservoir species populations, as indicated by specific trap success, varied greatly among parks. Of 52 Akodon azarae captured in Otamendi, 11 (21%) were reactive for ANDV.Oligoryzomys nigripes (N=10) and O. flavescens (N=12) were not positive. Antibody prevalence was approximately 14% for O. nigripes in El Palmar, however antibodies were not detected in 20 individuals of A. azarae captured in this site. Antibody-positive O. flavescens mice were found in Pre-Delta where the prevalence was 8.5% (10/118) but no positive animals were found in the 19 A. azarae captured. The seroprevalence was not associated with rodent density, richness or diversity in any areas. However, in the 3 protected areas, the proportion of males in the positive individuals was significantly higher than the proportion of males in the total population of the host ( pOtamendi= 0.04; pPre Delta= 0.007; pPalmar= 0.025), being generally the positive ones adult rodents. The O nigripes hosted Juquitiba virus while O.flavescens, ANDV Lechiguanas lineage. Conclusion: Evidence of pathogenic hantaviruses detected in reservoir populations indicates that potential risk exists for human infection througout National Parks studied.