Journal of Wildlife Diseases最新文献

{"title":"Prevalence of Trypanosoma cruzi Antibodies in Wild Pigs (Sus scrofa) in the USA.","authors":"Taylor A Fisher, Sarah M Coker, Raquel Francisco, Bailey Ward, Vienna R Brown, Michael J Yabsley, Ellen Haynes, Christopher A Cleveland","doi":"10.7589/JWD-D-25-00020","DOIUrl":"https://doi.org/10.7589/JWD-D-25-00020","url":null,"abstract":"<p><p>Wild pig (Sus scrofa) populations are expanding across the US, raising concerns about the ecologic impacts and role as reservoirs for pathogens of significance to human and animal health. Trypanosoma cruzi, the causative agent of Chagas disease, is a recognized risk for humans and domestic dogs in the southern US. Common wildlife reservoirs of T. cruzi include rodents (e.g., Neotoma spp.), raccoons (Procyon lotor), and Virginia opossums (Didelphus virginiana); however, there have been reports of T. cruzi infection in suids, including a domestic pig (Sus scrofa domesticus) in Mexico and three wild pigs in Texas, US. Our study aimed to better understand the prevalence and distribution of T. cruzi antibodies in wild pigs in the US. We collected 1,093 serum samples from wild pigs across 12 states in the southern, midwestern, and western regions of the US, all of which have populations of T. cruzi triatomine vectors. We tested sera for antibodies against T. cruzi using an indirect ELISA and detected an overall apparent prevalence of 14.6% (160/1,093; 95% confidence interval, 12.6-16.9%). Pig sex, age class, month of sampling, and region were not significantly associated with seroprevalence; however, state of origin explained some variation in the data. We demonstrated that wild pigs in the US were exposed to T. cruzi, highlighting the need for further research elucidating their role in T. cruzi transmission.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145081151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Besnoitia spp. Infection of the Testis, Peritesticular Structures, and Udder Skin in Migratory Caribou (Rangifer tarandus).","authors":"Laura Van Driessche, Julie Ducrocq, Susan Kutz, Brett Elkin, Joëlle Taillon, Steeve D Côté, Vincent Brodeur, Christine Cuyler, Stéphane Lair","doi":"10.7589/JWD-D-25-00005","DOIUrl":"https://doi.org/10.7589/JWD-D-25-00005","url":null,"abstract":"<p><p>We investigated the prevalence, cyst density, and any associated pathologic changes of Besnoitia spp. in the testis, peritesticular structures, and udder skin of migratory caribou (Rangifer tarandus). Possible risk factors for infection, cyst density, and inflammation were investigated. Samples from 149 male and 229 female caribou were collected from seven different herds across Canada, Alaska (US), and Greenland, 2007-09. Biopsies were taken from the udder skin in females and from the epididymis, scrotal skin, testis (seminiferous tubules and tunica albuginea), and spermatic cord in males. The cyst density (cysts per square millimeters) of Besnoitia spp. in each tissue, as well as the type of associated inflammation, were determined by histopathologic examination. Individual (age class) and environmental (season and herd) risk factors were investigated for infection, cyst density, and inflammation. Besnoitia spp. cysts were detected in 22.2, 20.4, 11.2, 31.3, 10.4, and 8.0% of the sections of epididymis, scrotal skin, seminiferous tubules, spermatic cord, tunica albuginea, and udder skin, respectively. The median cyst densities varied from 0.07 cysts/mm2 in the seminiferous tubules to 1.02 cysts/mm2 in the udder skin. Age class and season were risk factors for infection, so adults and subadults were more at risk than calves, and infection was more prevalent in the fall months (September to December) relative to other seasons. Subadults, however, demonstrated a higher cyst density compared with adults and calves. During the winter months, a higher risk of inflammation was present compared with other seasons. Overall, the intensity of inflammation was light to mild, and both pericystic and concomitant inflammation were commonly present. Further research should determine whether these parasitic cysts and the associated inflammation influence the functionality of the testis, peritesticular structures, and udder and thus reproduction.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145069921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recurring Streptococcal Outbreak Threats in Urban Long-Tailed Macaques (Macaca fascicularis) in Bali.","authors":"Laurie Patouillat, I Nengah Wandia, I Gusti N K Mahardika, Maria W Danastri, Pipit D Pramesti, Rinaldi Hutabarat, Nelviana Mesquita, Gwennan Giraud, Eva Gazagne, Fany Brotcorne, Mutien M Garigliany","doi":"10.7589/JWD-D-24-00225","DOIUrl":"https://doi.org/10.7589/JWD-D-24-00225","url":null,"abstract":"<p><strong>Abstract: </strong>Streptococcus equi ssp. zooepidemicus is a zoonotic bacterium known to cause severe respiratory tract infections in primates, and most documented mortality episodes occur in captivity. Here we report a mass mortality event in a wild population of long-tailed macaques (Macaca fascicularis) inhabiting an urban mosaic habitat in central Bali, Indonesia, and describe the demographic impact and clinical patterns of the outbreak. Mortality was observed in three of the nine social groups that shared overlapping ranges, and the infection spread progressively over time. Clinical signs included lethargy, respiratory distress, and locomotion disorders. Over a 2-mo period during March-May 2022, 170 carcasses were found. Demographic surveys revealed a mortality rate ranging from 16% to 53% among the three affected groups. Adult females and adult males were the most affected age-sex classes, representing 36% and 35% of the carcasses found, respectively. Necropsy findings from four individuals, combined with bacteriological culture, histopathology, qPCR, and 16S rRNA metabarcoding analysis, all suggested Streptococcus equi ssp. zooepidemicus as the most likely causative agent. Similar streptococcal outbreaks had occurred in this population in 1994 and 2012, raising concerns about the recurrent introduction of the bacterium or potential reservoirs either within or outside the macaque population. The recurrence of Streptococcus equi ssp. zooepidemicus outbreaks in this population highlights the impact of lethal bacterial epidemics in wild primates, which remain poorly documented. Strengthening long-term surveillance, including noninvasive serological monitoring, is essential for better understanding infection dynamics and improving conservation strategies.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145069918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lead Bullet Burden: Widespread Lead Exposure in Wild Carnivores and Unseen Consequences of Feeding Lead-Shot Meat to Captive Cheetahs (Acinonyx jubatus).","authors":"Catherine Hauw, Laurie Marker, John Yabe, María Díez-León, Niall McCann, Gerhard Iiputa, Mark Jago, Esther Mukete-Hilundutah, Trevor Nzehengwa, Nelly Banda, Shouta M M Nakayama, Mayumi Ishizuka, Utarera Katjavivi, Jacqueline Ehrlich, Marc Humphries, Anne Schmidt-Küntzel","doi":"10.7589/JWD-D-24-00219","DOIUrl":"https://doi.org/10.7589/JWD-D-24-00219","url":null,"abstract":"<p><p>Lead (Pb) exposure is a global concern because of its harmful effects on the environment, animals, and humans. Although research on Pb poisoning in humans and avian species is extensive, similar literature on mammalian carnivores is limited. Only two reports of suspected Pb poisoning in captive cheetahs (Acinonyx jubatus) exist, and none in wild cheetahs. We quantified cumulative life exposure to Pb in 62 cheetahs (33 males, 29 females) and 11 (unknown sex) leopards (Panthera pardus). Cheetahs were grouped according to time spent in captivity: wild (>10% of life in the wild) and captive (10-100% of life in captivity); all leopards were wild. Bone lead concentration (BLC) was measured in tibias to assess the effects of time in captivity, age, and sex on Pb exposure. Lead was detected in all cheetah and leopard tibias. Mean BLC was 1.11±1.92 mg/kg for all cheetahs, with a significantly higher mean in captive (1.57±2.25 mg/kg) versus wild (0.27±0.39 mg/kg) cheetahs. Time in captivity had a significant effect on BLC, with BLC increasing with years spent in human care. Wild leopards had a higher BLC than wild cheetahs, with a mean BLC of 1.02±1.56 mg/kg. Higher BLC in captive than wild cheetahs was attributed to Pb exposure from the ammunition used to shoot ungulates for their diet. Increased exposure in wild leopards might be attributable to opportunistic scavenging, a behavior not seen in wild cheetahs. This study highlights the need for non-Pb ammunition options in support of conservation and animal welfare.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145065088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observational, Virologic, and Serologic Data Provide Insights into an Outbreak of Highly Pathogenic Avian Influenza among Wild Birds on the Yukon-Kuskokwim Delta, Alaska, USA, in 2022.","authors":"Bryan L Daniels, Erik E Osnas, Megan L Boldenow, Robert F Gerlach, Christina A Ahlstrom, Sarah M Coburn, Michael J Brook, Michael Brubaker, Julian B Fischer, David N Koons, Angela C Matz, Marin A Murphy, Daniel J Rizzolo, Laura C Scott, David R Sinnett, Jordan M Thompson, Juliana B Lenoch, Mia Kim Torchetti, David E Stallknecht, Rebecca L Poulson, Andrew M Ramey","doi":"10.7589/JWD-D-24-00199","DOIUrl":"https://doi.org/10.7589/JWD-D-24-00199","url":null,"abstract":"<p><p>In 2021-22, clade 2.3.4.4b highly pathogenic avian influenza (HPAI) viruses were introduced by wild birds into North America, leading to geographically widespread disease. In response to HPAI outbreaks throughout late 2021 and early 2022, we recorded observations of sick and dead birds, estimated abundance of carcasses, collected swab and sera samples to detect viruses, and monitored bird nesting on the Yukon-Kuskokwim Delta region of Alaska to document potential effects of disease. Thirty-six reports of sick and dead birds were registered across the region. Nineteen carcasses were opportunistically collected for diagnostic testing, of which 12 were confirmed to be infected with clade 2.3.4.4b HPAI viruses. Carcass abundance estimates from line-distance sampling provided evidence that the most common species of dead birds from the western Yukon-Kuskokwim Delta region were Cackling Goose (Branta hutchinsii minima), Glaucous Gull (Larus hyperboreus), and Black Brant (Branta bernicla nigricans). Only one paired cloacal and oropharyngeal swab sample from a Northern Pintail (Anas acuta) tested positive for clade 2.3.4.4b HPAI virus, out of 464 live-captured duck and goose samples. Of 195 sera samples from waterfowl screened for antibodies reactive to influenza A viruses, antibodies were found in 41-98% of samples collected from Emperor Goose, Cackling Goose, Black Brant, and Spectacled Eider (Somateria fischeri). In addition, 15-98% of the same sera samples were reactive to a clade 2.3.4.4b H5 antigen. Fewer Black Brant and Emperor Goose nests were found on long-term study plots during 2022 than in previous years. Collectively, we found that HPAI viruses affected at least seven species of wild birds inhabiting the region during 2022. The full scope of impacts of HPAI at this location during 2022 is unknown, but our data indicate that acute effects to avian population health on the Yukon-Kuskokwim Delta region were likely modest.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145065156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ranavirus-Positive Hatchling Eastern Box Turtles (Terrapene carolina carolina) Suggest Vertical Transmission without Observed Disease.","authors":"Ryan J Rimple, Stacey L Lance, Kurt A Buhlmann, Michel T Kohl, Tracey D Tuberville","doi":"10.7589/JWD-D-24-00220","DOIUrl":"https://doi.org/10.7589/JWD-D-24-00220","url":null,"abstract":"<p><p>Ranaviruses (Iridoviridae) are highly virulent emerging pathogens that affect a wide range of ectotherms, including fishes, amphibians, and reptiles. In turtles, ranaviruses have contributed to deadly epizootic events in wild and captive populations. Despite ranaviruses being pathogens of major concern, their transmission is poorly understood in reptiles and the potential for vertical transmission (from mother to offspring) remains unaddressed. We investigated vertical transmission of ranavirus in eastern box turtles (Terrapene carolina carolina) by screening 25 reproductive females and their offspring (n=74). We collected samples from adult females up to four times during the 2022 reproductive season and, in some cases, for up to 3 yr prior. We collected samples from offspring at hatch in 2022 and approximately 8 mo later. We documented seven reproductive females with positive ranavirus detections, although no females tested positive at more than one time point and all detections occurred 2-3 yr before reproductive monitoring in 2022. We documented nine hatchlings from six clutches with positive ranavirus detections, seven of which were produced by four females without a documented history of ranavirus detection. None of the ranavirus-positive hatchlings exhibited clinical signs of disease throughout an 8-mo captive rearing period; five of seven initially positive hatchlings were negative at release, and all survived until release. Hatchlings in which we detected ranavirus exhibited low viral loads, and we found no evidence that they transmitted the virus to their clutchmates during captive rearing. Collectively, our results suggest that vertical transmission of ranavirus is possible in box turtles, but we found no evidence that the low viral loads we observed resulted in disease. Further research is needed to determine the precise mode of vertical transmission in turtles and to understand the potential individual and population-level effects of maternally derived infections.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Retrospective Analysis of Parasites in Wild-Caught Eastern Newts (Notophthalmus viridescens) Experimentally Exposed to Batrachochytrium salamandrivorans.","authors":"Taylor C Demers, Debra L Miller, Matthew J Gray, Xiaojuan Zhu, Timothy Wu, Wesley C Sheley","doi":"10.7589/JWD-D-24-00182","DOIUrl":"https://doi.org/10.7589/JWD-D-24-00182","url":null,"abstract":"<p><p>Amphibians are experiencing extinction rates over 200 times the background extinction rate. One emerging infectious disease contributing to amphibian declines is caused by the fungal pathogen Batrachochytrium salamandrivorans (Bsal), which has caused mass die-offs of fire salamanders (Salamandra salamandra) in Europe and could pose a major threat to North American salamander biodiversity if introduced to the continent. A recent study investigated the effects of pathogen dose and environmental temperature on Bsal chytridiomycosis disease progression in wild-caught Notophthalmus viridescens (eastern newts). During that study, necropsy and histologic examination revealed that many newts were infected with multiple parasites. We performed a retrospective analysis on the 41 eastern newts from that study to evaluate whether parasite load was related to Bsal load, environmental temperature, or host survival. In this study 34% (15/41) of newts were infected with nematodes and 22% (9/41) were infected with protozoans. Nematode loads were greatest in newts held at cooler temperatures. Additionally, there was a significant correlation between the overall parasite load and the survival time of newts infected with Bsal. Our results suggest that environmental temperature and parasite infection may interact to increase infection tolerance, which is consistent with recent results reported for Batrachochytrium dendrobatidis. Our results highlight the importance of studying micro- and macroparasite interactions and their possible impacts on host survival.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SARS-CoV-2 Antibodies in Wild Mammals from Atlantic Forest Region in Misiones province, Argentina.","authors":"Pamela A Kuhlmann, Dante L Di Nucci, Silvina N Valdez, Juan I Marfia, Ignacio Smith, María V Miranda, Candelaria Sanchez Fernandez, Emanuel Grassi, Erik Ruuth, Karina A Salvatierra","doi":"10.7589/JWD-D-25-00003","DOIUrl":"https://doi.org/10.7589/JWD-D-25-00003","url":null,"abstract":"<p><p>There is evidence that both domestic and wild animals are susceptible to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the virus causing COVID-19 in humans. However, the extent of infection in native wild mammals and the most susceptible species to SARS-CoV-2 remain unclear. We assessed SARS-CoV-2 exposure in native wild mammals from the Misiones region, a subtropical area in northeastern Argentina, within the Upper Paraná Atlantic Forest ecoregion. A descriptive, cross-sectional study was designed using serum samples from wild mammals that entered the Centro de Rescate, Rehabilitación y Recría de Fauna Silvestre Güirá Oga for veterinary care between December 2019 and March 2022. Epidemiological data were obtained from veterinary records, and antibodies against SARS-CoV-2 were detected using a novel bridge multispecies ELISA. A total of 115 serum samples from 26 wild mammal species were analyzed, revealing antibodies in 20 samples and a seroprevalence of 17.4% (95% confidence interval 11.5-25.3%). Antibodies were detected in 13 species, including native wild mammals in Argentina. These findings indicate that certain wildlife species may be infected by this virus, but do not provide evidence that any of the tested animals are reservoirs for SARS-CoV-2, as the study only addressed exposure. The results underscore the importance of continued surveillance to understand the ecological impacts of SARS-CoV-2, prevent zoonotic transmission, and protect both wildlife and human health.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Current Biosecurity Practices in the Handling and Sampling of Cervids: A Cross-Sectional Survey.","authors":"Valeriia Yustyniuk, Gretel A Keller, Marc D Schwabenlander, Kristin J Bondo, Sonja A Christensen, Tiffany M Wolf","doi":"10.7589/JWD-D-25-00007","DOIUrl":"https://doi.org/10.7589/JWD-D-25-00007","url":null,"abstract":"<p><p>Effective biosecurity practices are essential for mitigating the risks of pathogen transmission in human-wildlife interactions, yet it is unclear how infection control policies are put into action by those working with wildlife. We evaluated biosecurity practices among professionals working with cervids in the US and Canada via an electronic survey conducted between March 2024 and June 2024. The objectives were to identify pathogens of concern, describe current biosecurity protocols, evaluate the appropriateness of disinfecting practices, and explore associations between biosecurity practices and factors such as profession, regional disease status, and the nature of interactions with cervids. Survey respondents were primarily ecologists or biologists (47%), veterinarians (46%), and managers or wildlife capture professionals lacking those backgrounds (6%). Respondents identified chronic wasting disease (CWD) and SARS-CoV-2 as primary pathogens of concern, with CWD being the most frequently targeted for disinfection, even in nonendemic areas. Although most respondents indicated the use of biosecurity protocols, adherence was inconsistent, particularly in free-living settings. Professionals working with captive cervids were significantly more likely to consistently follow biosecurity protocols than those working exclusively with free-living cervids. Use of personal protective equipment was common. Veterinarians were more likely than managers lacking an ecology, biology, or veterinary background to disinfect cervid sampling equipment between individual animals. Those working in regions where CWD was endemic were more likely to have formal biosecurity policies and cleaning and disinfection protocols compared with those in nonendemic areas. Our study also identified biosecurity protocol gaps, with some respondents using ineffective disinfectants or suboptimal concentrations against reported pathogens of concern. These findings highlight the need for standardized, evidence-based guidelines when developing and implementing cervid biosecurity protocols, particularly regarding effective disinfectant use.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145015774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pathologic Characterization of Highly Pathogenic H5N1 Avian Influenza Virus Infections in Wild Mammals in Alaska, USA.","authors":"Kimberlee B Beckmen, Kathleen A Burek Huntington, Terry Spraker, Jayne Ellis","doi":"10.7589/JWD-D-25-00023","DOIUrl":"https://doi.org/10.7589/JWD-D-25-00023","url":null,"abstract":"<p><p>This report describes highly pathogenic avian influenza virus (HPAI) H5N1 infections in carnivores in Alaska, US between 2022 and 2024, including a black bear (Ursus americanus), a brown bear (Ursus arctos), and the first known report of HPAI in an ermine (Mustela ermina). The two bears were cubs, and the ermine was a young adult. The black bear and ermine were euthanized after demonstrating neurologic signs, including circling, blindness, ataxia, or seizures. The brown bear was found dead. Gross lesions included swelling and congestion of the brain in both bears. Microscopically, all three individuals exhibited severe, nonsuppurative necrotizing meningoencephalitis, which was most prominent in the gray matter. Nonneuropathic microscopic lesions shared between both bears were multifocal random hepatic necrosis with lymphoplasmacytic hepatitis and mild interstitial pneumonia with bronchitis. The spectrum of additional lesions in individual animals consisted of acute necrosis within multiple other organs, including skeletal muscle, pancreas, kidney, retina, adrenal glands, and intestine. Immunohistochemistry demonstrated positive staining within neurons and glial cells in the brain, enterocytes and neurons of the myenteric plexus in the intestine, rare bronchiolar epithelial cells, renal tubular epithelial cells, and myocyte nuclei. Two HPAI-positive red foxes (Vulpes vulpes) and one positive Arctic fox (Vulpes lagopus) with incomplete histopathology are briefly discussed, as they demonstrate potential for co-infections with HPAI and canine distemper virus or rabies virus.</p>","PeriodicalId":17602,"journal":{"name":"Journal of Wildlife Diseases","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145000921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}