Confirmation of the invasive American mink (Neogale vison) as carrier of Mycobacterium bovis in southern Chile

• Published in: Acta tropica Vol. 256; p. 107257
• Main Authors: Hernández, Felipe A., Tejeda, Carlos, Aristizábal, Brandon, Raffo, Eduardo, Moroni, Manuel, Salgado, Miguel
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.08.2024
• Subjects: Bovine tuberculosis; Invasive carrier; Mycobacterium bovis; Neogale vison; QPCR; Invasive carrier; QPCR; Mycobacterium bovis; Bovine tuberculosis; Neogale vison
• ISSN: 0001-706X; 1873-6254; 1873-6254
• DOI: 10.1016/j.actatropica.2024.107257

Bovine tuberculosis (bTB) is a chronic infectious-contagious disease with worldwide distribution, caused by the zoonotic pathogen Mycobacterium bovis. It is believed that the existence of wild cycles may hamper the success of bTB control strategies worldwide, where wildlife species could be reservoirs of this bacterial agent across their native (e.g., European badgers, wild boars) or non-indigenous (e.g., brushtail possum in New Zealand) ranges. However, further studies are required to understand the potential risk posed by non-native wildlife in becoming carriers of M. bovis in other neglected latitudes, such as the Southern Cone of South America. In this study, we performed a specific M. bovis-RD4 real-time PCR (qPCR) assay to detect bacterial DNA in tissues from the invasive American mink (Neogale vison) in Los Ríos region, Chile. We detected M. bovis DNA in blood samples collected from 13 out of 186 (7 %) minks with known sex and age. We did not find any significant differences in bacterial DNA detection according to mink sex and age. We found that 92 % (12/13) of specimens were positive in lung, 39 % (5/13) in mediastinal lymph node, and 15 % (2/13) in mesenteric lymph node, which suggest that both respiratory and digestive pathways as possible routes of transmission between infected hosts and minks. Our study is the first report on M. bovis molecular detection in invasive minks in an area where the largest cattle population in the country is located. Furthermore, this area is characterized by a low within-herd prevalence of M. bovis infection in cattle, with a relatively low number of infected herds, and so far, no attempts at eradicating the disease have been successful.