Biology subjects

Hungnes, O.

Publications and source records attributed to Hungnes, O..

5 recordsLinked to original sources

bioRxiv2026

Highly Pathogenic Avian Influenza Viruses H5N1 and H5N5 in Red Foxes (Vulpes vulpes) in Norway during 2022-2024

Since 2020, highly pathogenic avian influenza (HPAI) A(H5Nx) clade 2.3.4.4b viruses have spread globally, causing extensive outbreaks in domestic and wild birds. Increased circulation has resulted in frequent spillover to mammals, and occasional mammal-to-mammal transmission. Although human infections remain rare, the zoonotic potential of these viruses continues to be a public health concern. We investigated six cases of HPAI in red foxes (Vulpes vulpes) in Norway during 2022-2024 and identified infections with H5N1 and H5N5 viruses. Pathological and virological investigations demonstrated systemic infection, with prominent lesions in the brain and/or lungs. Phylogenetic analyses showed high similarity between viruses detected in foxes and those concurrently circulating in wild birds. The mammalian adaptation marker PB2:E627K was identified in one H5N1 virus and as a minority variant in a second H5N1 virus.

microbiology↗

bioRxiv2026

Serological Evidence of Widespread Exposure to H5 Avian Influenza Virus in Arctic Foxes in Svalbard, Norway

The continued circulation of H5 clade 2.3.4.4b highly pathogenic avian influenza virus (HPAIV) has caused extensive mortality in wild bird populations worldwide with increasing spillover to mammals. In 2022, H5 HPAIV emerged in Svalbard, Norway, with subsequent detections in wild birds, walruses, polar bears, and arctic foxes. To understand the population-level exposure among Svalbard arctic foxes, we analysed body fluids from carcasses trapped in 2006-2015 (n = 56), 2023-2024 (n = 112), and 2024-2025 (n = 94) for antibodies to H5 avian influenza (anti-H5), influenza A nucleoprotein (anti-NP), and neuraminidase subtypes using ELISAs, haemagglutination inhibition (HI), and a multiplex assay. Only three samples from 2006-2015 tested positive for anti-H5 and were interpreted as false positives. In 2023-2024, seropositivity for anti-H5 was high (95%), supported by a lower anti-NP seropositivity (85%) and antibody profiles consistent with mixed H5N1 (42%) and H5N5 (52%) exposure. In 2024-2025, anti-H5 and anti-NP seroprevalences remained high (83% and 57%), with H5N5 (87%) exposure predominating over H5N1 (3%). A subset of anti-H5-positive samples tested positive by HI (2023-2024: 30%; 2024-2025: 14%). Juveniles with exposure limited to the previous season had higher odds of anti-H5 seropositivity in 2023-2024 than in 2024-2025 (OR 5.5). Analysis of paired lung extracts from a subset of individuals (n = 63) yielded results concordant with body fluids, using an indirect anti-H5 ELISA adapted for carnivores. Our findings demonstrate widespread H5 virus exposure. Together with occasional reports of progression to fatal HPAI, this highlights the need for continued population monitoring to evaluate ecological consequences.

microbiology↗

bioRxiv2025

Highly Pathogenic Avian Influenza A(H5N1) Caused Mass Death among Black-legged Kittiwakes (Rissa tridactyla) in Norway, 2023

In 2023, highly pathogenic avian influenza (HPAI) heavily affected gulls in Europe. In July, a mass mortality event was reported in the Black-legged Kittiwake (Rissa tridactyla) breeding colony at Ekkeroy in Northern Norway. The cause was confirmed to be infection with the HPAI H5N1 clade 2.3.4.4b virus, genotype EA-2022-BB. We describe the outbreak in Kittiwakes, including pathological and virological investigations, and discuss the management and zoonotic potential. With more than 15,000 dead birds reported, we estimate that the outbreak caused a reduction in the Kittiwake population at Ekkeroy of at least 50%. Diseased birds exhibited neurological signs. Necropsy of ten birds revealed a peracute fatal systemic disease, with severe lesions in the brain and pancreas co-localizing with the presence of viral RNA and antigen. Vascular expression of 2,3-linked sialic acids and viral RNA/antigen may reflect hematogenous virus spread. Further studies should investigate the long-term impact of HPAI on Kittiwake populations.

microbiology↗

bioRxiv2024

Low levels of neutralizing antibodies against SARS-CoV-2 KP.3.1.1 and XEC in serum from seniors in May 2024

New immune evasive variants of SARS-CoV-2 may increase infections and hospitalizations in risk groups, such as the elderly. In this study we evaluated neutralizing antibodies against KP.3.1.1 and XEC, virus variants that are either widely distributed or on the rise globally, in sera from a cohort of seniors aged 68 - 82 years from April/May 2024. Neutralizing responses were low against both KP.3.1.1 and XEC, supporting the recommendation of an updated covid-19 vaccine booster in this age group.

immunology↗

bioRxiv2023

Poor neutralizing antibody responses against SARS-CoV-2 Omicron BQ.1.1 and XBB in Norway in October 2022

New sub-lineages of the SARS-CoV-2 omicron variants with enhanced ability to evade existing antibody responses continue to evolve. A better understanding how susceptible emerging virus variants are to immunity induced by vaccination or infection could help predict which strains will become dominant going forward. Here we evaluate neutralizing antibodies against several clinical isolates of omicron variants including BQ.1.1 and XBB in sera from 3x mRNA vaccinated individuals and individuals with breakthrough infections with early (BA.1 or 2) or late (BA.5) omicron variants. In addition, we evaluate neutralizing antibodies in serum samples harvested from 32 individuals from the middle of October 2022, to provide a more recent estimate of immunity. As expected, serum samples harvested after breakthrough infections were more efficient at neutralizing all the omicron variants, compared to sera from non-infected individuals. While neutralization remained high against variants such as BA.2.75.2, BR.1 and BF.7, there was a marked reduction in neutralizing titers against BQ.1.1 and XBB. Similarly, most serum samples harvested in October 2022 had very low neutralizing antibodies against BQ.1.1 and XBB, suggesting that these variants and their descendants will dominate infection waves in Norway this winter season.

immunology↗