{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T08:37:59Z","timestamp":1786523879620,"version":"build-2736575974"},"reference-count":24,"publisher":"Wildlife Disease Association","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal of Wildlife Diseases"],"published-print":{"date-parts":[[2026,4,20]]},"abstract":"<jats:p>Knowledge of the occurrence and etiology of cetacean diseases remains limited in northern areas, including in the Arctic and sub-Arctic. In November 2023, three killer whales (Orcinus orca) were observed in northern Norway exhibiting abnormal behavior, including inability to swim upright, loss of directional control, short and shallow dives, and lethargy. These unusual cases occurred within a 2-wk period and in the same area, suggesting a common underlying condition. However, due to the lack of diagnostic biologic samples, the cause of disease remains speculative. Herein, we discuss possible differential diagnoses based on the available data, including infectious disease, exposure to biotoxins, and blast trauma. Disease in live free-swimming killer whales in Norway has not been documented previously. These cases illustrate the significant challenges of investigating disease in wild, live cetaceans and emphasize the urgent need for improved surveillance, field diagnostic tools, and response protocols. Suggested developments include the implementation of ready-to-use kits for blow, fecal, and environmental DNA sampling; drones equipped with sampling devices and thermal sensors; and mobile laboratories to support on-site diagnostics. Collectively, these tools could significantly improve early detection, investigation, and management of similar unusual events in wild cetacean populations.<\/jats:p>","DOI":"10.7589\/jwd-d-25-00055","type":"journal-article","created":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T05:49:23Z","timestamp":1776664163000},"page":"452-458","source":"Crossref","is-referenced-by-count":0,"title":["Disease Investigation in Norwegian Killer Whales (Orcinus orca): Challenges and Needs for Improving Free-Living Cetacean Health Assessments"],"prefix":"10.7589","volume":"62","author":[{"given":"Helena","family":"Costa","sequence":"first","affiliation":[{"name":"Faculty of Biosciences and Aquaculture, Nord University, Universitetsall\u00e9en 11, Bod\u00f8 8026, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Audun H.","family":"Rikardsen","sequence":"additional","affiliation":[{"name":"Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Hansine Hansens veg 18, Troms\u00f8 9019, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marie-Anne","family":"Blanchet","sequence":"additional","affiliation":[{"name":"Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Hansine Hansens veg 18, Troms\u00f8 9019, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eve","family":"Jourdain","sequence":"additional","affiliation":[{"name":"Norwegian Orca Survey, Breivikveien 10, Andenes 8480, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Courtney A.","family":"Waugh","sequence":"additional","affiliation":[{"name":"Faculty of Biosciences and Aquaculture, Nord University, Universitetsall\u00e9en 11, Bod\u00f8 8026, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierre","family":"Bl\u00e9vin","sequence":"additional","affiliation":[{"name":"Akvaplan-niva AS, Fram Centre, Hjalmar Johansens gate 14, Troms\u00f8 9007, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"4415","reference":[{"key":"1","doi-asserted-by":"crossref","unstructured":"C Andvik, E Jourdain, A Ruus, et al.  \"Sci Rep.\"  10, \"Preying on seals pushes killer whales from Norway above pollution effects thresholds.\" 11888 (2020)","DOI":"10.1038\/s41598-020-68659-y"},{"key":"2","doi-asserted-by":"crossref","unstructured":"MC Bento, R Canha, C Eira, et al.  \"Infect Genet Evol.\"  67, \"Herpesvirus infection in marine mammals: A retrospective molecular survey of stranded cetaceans in the Portuguese coastline.\" 222 (2019)","DOI":"10.1016\/j.meegid.2018.11.013"},{"key":"3","doi-asserted-by":"crossref","unstructured":"P Bories, AH Rikardsen, P Leonards, et al.  \"Ecol Evol.\"  11, \"A deep dive into fat: Investigating blubber lipidomic fingerprint of killer whales and humpback whales in northern Norway.\" 6716 (2021)","DOI":"10.1002\/ece3.7523"},{"key":"4","doi-asserted-by":"crossref","unstructured":"H Costa, P Ramstedt, M Bergsma, et al.  \"BMC Vet Res.\"  21, \"Deep breath out: Molecular survey of selected pathogens in blow and skin biopsies from North Atlantic cetaceans.\" 709 (2025)","DOI":"10.1186\/s12917-025-05152-6"},{"key":"5","doi-asserted-by":"crossref","unstructured":"J Charostad,  Rezaei Zadeh Rukerd, S Mahmoudvand, et al.  \"Travel Med Infect Dis.\"  55, \"A comprehensive review of highly pathogenic avian influenza (HPAI) H5N1: An imminent threat at doorstep.\" 102638 (2023)","DOI":"10.1016\/j.tmaid.2023.102638"},{"key":"7","doi-asserted-by":"crossref","unstructured":"KR Groch, SA Taniwaki, CM Favero, et al.  \"J Virol Methods.\"  285, \"A novel real-time PCR to detect Cetacean morbillivirus in Atlantic cetaceans.\" 113964 (2020)","DOI":"10.1016\/j.jviromet.2020.113964"},{"key":"8","doi-asserted-by":"crossref","unstructured":"SE. 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