The Pyrenean chamois (Rupicapra pyrenaica pyrenaica) is the most common alpine ruminant species in the Pyrenees (Northern Spain – Andorra – Southern France). Since 2001, chamois populations have suffered devastating outbreaks of fatal disease caused by a Pestivirus (Border Disease Virus – BDV). This disease has reduced chamois density resulting in the collapse of the chamois populations in some geographic areas.
Recently, our research group demonstrated the existence of two circulating BDV strains of different virulence, adapted to chamois populations. One of the two Pestivirus is a highly virulent BDV strain, that causes long-lasting fatal disease with a high transmission rate to other individuals. The mortality rates reached 85% in some geographic areas after the entrance of the high virulent BDV into previously unexposed chamois populations .
In our recent studies, we have also demonstrated the circulation of a low virulent BDV in the Eastern Pyrenees without a significant impact on the chamois population. To date, no mass mortality has been reported in this area, where more than a half of the chamois population have neutralizing antibodies against Pestivirus. The low virulent BDV infection in chamois results in a subclinical disease. We suggest that the circulation of the low virulent BDV in this population have protected the chamois against the high virulent BDV strain.
Although its conservation status is considered as Least Concern by the International Union for the Conservation of Nature, the presence of the high virulent Pestivirus, together with other endemic diseases is of concern for the future management of Pyrenean chamois.
Additionally, the activity of our research team is focused on the study of the emergence of infectious diseases in the Pyrenees. Due to global climate change, alpine ecosystems are suffering dramatic transformations at different levels, such as the emergence of unreported vectors (and their associated vector-borne diseases) with unpredictable consequences for alpine wildlife conservation.