A parasite outbreak in notothenioid fish in an Antarctic fjord

• Published in: iScience
• Main Authors: Desvignes, Thomas, Lauridsen, Henrik, Valdivieso, Alejandro, Fontenele, Rafaela, S, Kraberger, Simona, Murray, Katrina, N, Le François, Nathalie, R, Wiliam Detrich III, H., Kent, Michael, L, Varsani, Arvind, Postlethwait, John, H
• Other Authors: Institute of Neuroscience, University of Oregon, Eugene, Oregon, University of Oregon Eugene, Aarhus University Aarhus, Interactions Hôtes-Pathogènes-Environnements (IHPE), Université de Perpignan Via Domitia (UPVD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Institute of Marine Sciences / Institut de Ciències del Mar Barcelona (ICM), Consejo Superior de Investigaciones Cientificas = Spanish National Research Council (CSIC), Arizona State University Tempe (ASU), Biodôme de Montréal, Northeastern University's Marine Science Center, Northeastern University Boston, Oregon State University (OSU), School of Life Sciences (Arizona State University), University of Cape Town
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDV.EE.BIO]Life Sciences [q-bio]/Ecology; environment/Bioclimatology; [SDV.BA.MVSA]Life Sciences [q-bio]/Animal biology/Veterinary medicine and animal Health; Antarctic; Antarctic Peninsula; Southern Ocean; Antarc*
• Online Access: https://hal.science/hal-04000063; https://hal.science/hal-04000063/document; https://hal.science/hal-04000063/file/Desvignes-2022-iSci-Parasite.pdf; https://doi.org/10.1016/j.isci.2022.104588

International audience Climate changes can promote disease outbreaks, but their nature and potential impacts in remote areas have received little attention. In a hot spot of biodiversity on the West Antarctic Peninsula, which faces among the fastest changing climates on Earth, we captured specimens of two notothenioid fish species affected by large skin tumors at an incidence never before observed in the Southern Ocean. Molecular and histopathological analyses revealed that X-cell parasitic alveolates, members of a genus we call Notoxcellia, are the etiological agent of these tumors. Parasite-specific molecular probes showed that xenomas remained within the skin but largely outgrew host cells in the dermis. We further observed that tumors induced neovascularization in underlying tissue and detrimentally affected host growth and condition. Although many knowledge gaps persist about X-cell disease, including its mode of transmission and life cycle, these findings reveal potentially active biotic threats to vulnerable Antarctic ecosystems.