Sarcoptic Mange Outbreak Decimates South American Camelid Populations in San Guillermo National Park, Argentina
August 2021
Studysummary This study found that sarcoptic mange significantly decreased vicuña and guanaco populations in San Guillermo National Park, Argentina, likely originating from mange-infected llama introduced nearby, raising the risk of local extinction. Our plain-language summary of this paper — not a Tressless recommendation.
In San Guillermo National Park, Argentina, a sarcoptic mange outbreak from 2017 to 2019 severely impacted vicuña and guanaco populations, with a 68% and 77% decrease in their densities, respectively, and no individuals recorded by April 2019, indicating near-local extinction. Clinical signs of mange were observed in 24% of live vicuña and 33% of live guanaco, and in 94% of vicuña and 85% of guanaco carcasses. Histological examination confirmed sarcoptic mange as the cause, and genetic analysis suggested a single source of the outbreak. The introduction of mange-infected llama through a governmental program in 2009 is hypothesized to have triggered the outbreak, underscoring the potential for devastating effects on native wildlife from accidental disease introduction.
