Spatial distribution model of the Hantavirus reservoir, the long-tailed colilargo (Oligoryzomys longicaudatus), in Argentina.

CARBAJO A. E.; PARDIÑAS U. F. J.

JOURNAL OF MAMMALOGY

American Society of Mammalogists

Lugar: Champaign, Illinois; Año: 2007 vol. 88 p. 1555 - 1568

0022-2372

The first step in understanding the ecology of rodents as reservoirs and their relation with the disease they transmit is to determine their geographical distribution. This distribution can be modelled as a function of environmental variables. An extensive database of hantavirus reservoir Oligoryzomys longicaudatus (Muridae: Sigmodontinae) records was georeferenced in Argentina. Generalized linear models were used to model the reservoir presence probability as a function of environmental variables. The variables used in the multiple logistic regression were temperature, precipitation, evapotranspiration, altitude, tree cover, grass cover, bare soil cover, distance to rivers, to water bodies and to roads; also two phytogeographic classifications were included. Spatial autocorrelation was considered in the model by including a spatial dependence covariate. The best model included temperature and precipitation as explanatory variables, and it was improved by the fitting of the spatial covariate. The external validation showed that the model without space covariate correctly classified 95% of the sites with the rodent and 70% of the sites without it; the model including the spatial term correctly classified 100% of the sites with the rodent and 70% of the sites without it. A secondary model included days with frost and bare soil percentage cover as explanatory variables. O. longicaudatus was recorded for the first time in the Espinal phytogeographic province, the central and the eastern Patagonian plateaus. The percentages of sites with long-tailed colilargo records were in the High Andean/Subantarctic regions (97%), Pampean (0%) and Monte/Espinal/Patagonian (65%).