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Biologial Sciences Expands the Wonderful World of Mouse Trapping to the Southern Hemisphere by Dr. Amy Kuenzi by Dr. Rick Douglass
 Figure 1: The (Peromyscus maniculatus) is the reservoir of Sin Nombre Virus which causes Hantavirus with Pulmonary Syndrome (HPS) in the United States.
 Figure 2: A coli largo (Oligorysomes longicaudatis) is the reservoir of the Andes Virus that causes HPS in humans in Argentina and Chile.
 Figure 3: Peridomestic sites being studied in Patagonia on the eastern edge of the Andes.
Figure 4: A sylvan rodent study area between the Andean Steppe and the Notophagus Forest in Patagonia.
Figure 5: A simulated outbuilding (galpone) used in peridomestic rodent/hantavirus studies in Patagonia.
Figure 6: Luciana and Martin in the Montana Tech truck heading out in typical Montana weather to trap mice in Patagonia.Montana Tech professors Amy Kuenzi and Rick Douglass are collaborating With Patagonian (Argentina) researchers Luciana Piudo (Universidad del Comahue) and Martin Monteverde (University of Buenos Aeries) on studies of hantavirus/rodent ecology. Hantaviruses have been known as rodent borne diseases that affect humans since the Korean War. In 1993, an outbreak of hantavirus with pulmonary syndrome (HPS) occurred in the four corners region of the US. The virus that caused the outbreak was named Sin Nombre Virus (SNV). Later that year, two people in Montana died from HPS. By 1994, CDC initiated large scale longitudinal studies of deer mice (Figure 1), the rodent reservoir for SNV, in Montana (Douglass, et. al. 1996 and Douglass, et. al. 2001), Colorado, New Mexico and Arizona. Douglass and later, Kuenzi (Kuenzi, et. al. 2000, 2001, 2005), have been conducting studies in both sylvan (wild natural environments) and peridomestic (in and around human dwellings) studies with the goal of developing mechanisms to reduce human risk of contracting HPS.
In 1995, an HPS outbreak occurred in Patagonia and Dr. Nadia Guthmann, one of our other colleagues who has performed extensive small mammals studies (e.g. Guthmann, et. al. 1997), captured the first rodent in Patagonia (Calderon, et. al., 1999) (a coli largo, Figure 2) carrying a hantavirus. That virus was named the Andes Virus. Some work has been done in Patagonia in sylvan areas but, as in the US, most HPS cases are contracted in peridomestic settings. After seeing our work in peridomestic settings, Piudo and Monteverde invited us to collaborate with them in studies of coli largos/Andes virus in peridomestic settings (Figure 3) located on the foothills of the Andes (Figure 4).
Two studies are underway in Patagonia. The first compares population dynamics and infection dynamics in buildings (Figure 3) to those in sylvan habitats (Piudo, et. al. 2005) (Figure 4). Kuenzi and Douglass did similar work (Kuenzi, et. al. 2000, 2001) in Montana but we did not remove animals during each monthly sampling period. Luciana and Martin are working in buildings occupied by people and they are required to remove animals each month.
Because removal creates a dispersal sink (Douglass, et. al. 2003), Patagonian peridomestic study results are somewhat different than we found in Montana. To remove the “removal variable”, Martin has constructed some small experimental outbuildings (galpones) in and around which he is conducting several experiments (Figure 5).
The results between Montana and Patagonian rodent/ecology studies have many similarities and some striking differences. However, if you don’t look at the vegetation too closely, you have to keep reminding yourself in which country you are working. The environments are very similar (Figure 6). The most significant difference between north and south is how much our very talented colleagues can do with so little resources.
References: Calderón, G.; N. Pini; J. Bolpe; S. Levis; J. Mills; E. Segura; N. Guthmann; G. Cantoni; J. Becker; A. Fonollat; C. Ripoll; M. Bortman; R. Benedetti; M. Sabattini & D. Enria. 1999. Hantavirus Reservoir Hosts Associated with Peridomestic Habitats in Argentina. Emerging Infectious Diseases 5(6): 792-797.
Douglass, R.J., R. Van Horn, K.W. Coffin and S.N. Zanto, 1996. Hantavirus in Montana deer mouse populations: Preliminary results, Wildlife Diseases 32:527-530.
Douglass, RJ, T. Wilson, W.J. Semmens, S.N. Zanto, C.W. Bond, R.C. Van Horne and J.N. Mills. 2001 Longitudinal studies of Sin Nombre Virus in deer mouse dominated ecosystems of Montana. American Journal of Tropical Medicine and Hygiene. 65:33-41.
Douglass, RJ, AJ, Kuenzi, CY Williams, SJ Douglass, 2003. Removing deer mice from buildings: potential effects on risk of human exposure to Sin Nombre Virus. Emerging Infectious Diseases. 9:390-392.
Guthmann, N.; M. Lozada; J.A. Monjeau & K. Heinemann. 1997. Population dynamics of five sigmodontine rodents of northwestern Patagonia. Acta Theriologica 42 (2): 143-152.
Kuenzi, A. J., R. J. Douglass, and C. W. Bond. 2000. Sin Nombre Virus in deer mice captured inside homes, southwestern Montana. Emerging Infectious Diseases 6:386-388.
Kuenzi, AJ, R.J. Douglass, D. White, Jr., C.W. Bond and JN Mills, 2001. Antibody to Sin Nombre Virus in rodents associated with peridomestic habitats in west central Montana. American Journal of Tropical Medicine and Hygiene 64:137-146.
Kuenzi, A. J., R. J. Douglass, C. W. Bond, C. H. Calisher, and J. N. Mills. 1005. Long term dynamics of Sin Nombre Viral RNA and antibody in deer mice in Montana. Journal of Wildlife Diseases 41:473-481.
Piudo L, M Monteverde, S González Capria, P Padula, and P Carmanchahi. 2005. Distribution and abundance of sigmodontine rodents in relation to hantavirus in Neuquén, Argentina. J. of Vector Ecology. 30(1).
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