Epidemiology and Infection

Research Article

Contact rates and exposure to inter-species disease transmission in mountain ungulates

C. RICHOMMEa1, D. GAUTHIERa2 and E. FROMONTa3 c1

a1 Laboratoire Départemental Vétérinaire, Chambéry, France

a2 Laboratoire Départemental Vétérinaire et d'Hygiène Alimentaire, Gap, France

a3 U.M.R. C.N.R.S. 5558, Université Lyon 1, Villeurbanne, France

SUMMARY

The risk for a pathogen to cross the species barrier depends on the rate of efficient contacts between the species. However, contact rates between species have rarely been estimated from observations. Here we estimate contact rates and exposure of chamois Rupicapra rupicapra and Alpine ibex Capra ibex exposed to domestic pasteurellosis and brucellosis carried by sheep or cattle herds summering in mountain pastures. We use field observation data on animal positions treated in a geographic information system (GIS). Comparing 10 pastures, we show that the management of domestic herds influences the risk of inter-species transmission. Exposure to direct transmission of pasteurellosis is high when herds are not guarded nor enclosed, whereas exposure to indirect transmission of brucellosis is increased on epidemiological dangerous points such as salt deposits. Our preliminary results need further investigation, but they underline the importance of both herd management and pathogen transmission mode when the aim is to reduce the risk of contamination of wild populations by a pathogen associated with domestic pathogens.

(Accepted April 18 2005)

(Online publication June 30 2005)

Correspondence:

c1 Author for correspondence: Dr E. Fromont, UMR 5558 Laboratoire de Biométrie et Biologie Evolutive, Bâtiment Mendel 1er étage, Université Claude Bernard Lyon 1, 43 bd du 11 novembre 1918, 69622 Villeurbanne Cedex, France. (Email: fromont@biomserv.univ-lyon1.fr)

Metrics