ETIDIOH - NEW

  ABSTRACT Swine influenza A virus (swIAV) is an important pathogen with regard to both the swine industry and public health . The pandemic A(H1N1) 2009 outbreak was caused by the swine-origin pandemic A(H1N1) 2009 [A(H1N1)pdm09] virus. Several reports have shown that several amino acid substitutions in the hemagglutinin (HA) antigenic sites can alter HA antigenicity. However, the impact of the amino acid deletion at position 155 on HA antigenicity remains unknown. In this study, we have isolated 11 samples of swIAVs from seven pig farms in Japan and found an amino acid deletion at position 155 of the HA region in one of the isolates of the H1N2 subtype . To examine the impact of this amino acid deletion on viral replication and HA antigenicity, we generated recombinant influenza A viruses possessing the H1 HA gene encoding either an artificial insertion or deletion of glycine at position 155. The growth kinetics of these recombinant viruses in two different cell lines demonstrated...

  Abstract Objective The H7N9 avian influenza virus, identified in China in 2013, has posed a significant threat to public health due to its high mortality rate . This systematic review aims to evaluate the clinical characteristics and mortality risk factors of H7N9 patients. Methods English and Chinese databases (PubMed, Web of Science, Embase, CNKI, VIP, Wanfang) were searched for studies on laboratory-confirmed H7N9 cases with available data on symptom onset, diagnosis time, clinical features, oseltamivir administration, and outcomes . Univariate and multivariate analyses were performed on the pooled case data to assess the relationship between clinical factors and mortality risk. Results A total of 166 studies including 237 H7N9 cases were analyzed , with an overall mortality rate of 41.77%. Univariate analysis showed higher mortality in patients with advanced age ≥ 66 years (62.50%), those with underlying diseases (60.20%), those who received oseltamivir ≥ 8 days after symptom...

  Abstract B etween 2022 and 2025, highly pathogenic avian influenza viruses (HPAIVs) of clade 2.3.4.4b, including four distinct H5 Eurasian (EA) genotypes , were detected in wild birds and mammals in the Svalbard Archipelago and on the island of Jan Mayen . We describe their epidemiology and genomic characteristics to improve understanding of HPAIV occurrence and transmission in the High Arctic . The initial cases in 2022 occurred during summer and involved a glaucous gull (Larus hyperboreus) and great skuas (Stercorarius skua) on Svalbard and Jan Mayen , representing the first detections of HPAIVs in the High Arctic . Three HPAIV genotypes were identified: EA-2020-C (H5N1), EA-2021-AB (H5N1), and EA-2021-I ( H5N5 ). In 2023 , HPAIVs were detected in a broader range of bird species, and retrospectively in an Atlantic walrus reported by another research group (Odobenus rosmarus rosmarus). Genotypes identified in 2023 were EA-2020-C (H5N1), EA-2021-I ( H5N5 ), and EA-2022-BB (H5N1)....

  Highlights •  Concern over H5N1 bird flu testing and detection in the Netherlands is increasing. •  50 human laboratories in the Netherlands, Aruba, Bonaire , and Curacao were assessed. •  The laboratories detected animal influenza viruses with high performance. •  Few laboratories identified the animal subtype of detected influenza A viruses. •  National reference laboratory capacity to identify the animal subtype is critical. Abstract Background Since 2022, highly pathogenic H5N1 influenza A virus clade 2.3.4.4b has caused global outbreaks among wild birds and poultry , with increasing mammalian and sporadic human infections . This elevates concerns about zoonotic transmission and pandemic risk , highlighting the need for accurate detection and identification of animal influenza A viruses by human clinical diagnostic laboratories (hCDL). Methods To evaluate routine diagnostic performance , an External Quality Assessment (EQA) panel containing inactivate...

  Abstract Despite Antarcticas geographic isolation, the first incursion of high pathogenicity avian influenza (HPAI) H5N1 was detected in the 2023/24 austral summer . Surveillance for HPAI H5N1 in Antarctica remains patchy due to logistical, financial, and infrastructure challenges , with many suspected cases remaining unconfirmed , and few viral genomes sequences available to date. Through the 2024/25 austral summer we undertook five sampling expeditions to the South Shetland Islands and Antarctic Peninsula facilitated by cruise ships/operators. Across more than 500 faecal environmental samples collected from apparently healthy penguins and marine mammals , we found no detectable evidence of HPAI H5N1 . However, HPAI H5N1 was detected in all but one of the skua carcasses sampled , which, in most cases, were found within meters of penguin sub-colonies . All HPAI H5N1 viral genomes sequences from skuas on the Antarctic Peninsula fell within a single lineage, which included those ge...

  Abstract FluSurvey is a participatory surveillance system used to monitor trends in influenza and other respiratory viruses through weekly symptom surveys among the UK population. We aimed to characterise the wider impact of influenza-like illnesses (ILI) among FluSurvey participants and assess correlations of ILI with other established influenza surveillance systems . We included data reported by FluSurvey participants over the 2023-24 and 2024-25 winter seasons . Using weekly symptoms surveys, we derived ILI episodes and estimated the proportion reporting healthcare service use , medication use, impact on daily life, absenteeism and use of tests. We applied existing data methods (omitting first report and weighting to the age-sex structure of England) and assessed cross-correlations of weekly FluSurvey ILI rates with the national surveillance of GP ILI consultations , influenza hospital admissions, and influenza PCR test positivity at time lags of up to +/-2 weeks. There were 3...

  Abstract After rebounding from near extirpation during the organochlorine era, breeding Peregrine Falcons (Falco peregrinus) in California are again facing adversity, this time consistent with an outbreak of a highly pathogenic avian influenza . Following the first detection of the H5N1 variant clade 2.3.4.4b virus in California wild birds in July 2022, we assembled data from long-term monitoring (2000-2025) of peregrine breeding territory occupancy in the broad vicinity of San Francisco Bay to examine possible impacts on falcon populations. Prior to the outbreak, 47 focal breeding territories had shown nearly complete occupancy by pairs (98.5% of 390 site-years), with very few vacancies, single birds in attendance, or subadult pair members. Within 8 mo of the outbreak, occupancy had dropped to 65.1%, and 2 yrs later (2025), only 36.2% of sites remained occupied . An uptick in site-occupancy by single birds also occurred after the outbreak, but it is unclear whether these were su...

  Abstract Clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) viruses continue to expand geographically and across mammalian hosts, raising concern about pandemic potential. The degree and specificity of pre-existing immunity in humans are key determinants of this risk. We analyzed hemagglutinin (HA)- and neuraminidase (NA)-specific antibody responses in 300 sera collected from adults in New York City. While HA directed binding antibodies to clade 2.3.4.4b H5 were low and hemagglutination-inhibiting antibodies were absent, we detected widespread binding and functional NA antibodies against N1 neuraminidases from clade 2.3.4.4b H5N1 viruses. Neuraminidase inhibition (NI) titers were highest against North American D1.1 genotype N1 viruses and correlated strongly with neutralizing activity, whereas HA-binding antibodies did not. An additional N-linked glycosylation site, as found in the NA of a human D1.1 isolate from British Columbia, reduced susceptibility to NI antibodies. An...

  Highlights •  A swine influenza virus H3N2 subtype was isolated during epidemiological survey. •  It is a complex and novel reassortant , and acquired accumulation of adaptive mutations. •  Both rescue and parent strains demonstrated efficient replication in mammalian cells. •  Key residues of the H3N2 HA collectively enhance the binding preference for human-type receptor. •  The rescued H3N2 cause significant pulmonary pathological damage in mice. Abstract Pigs serve as key "mixing vessels" for influenza A viruses, playing a critical role in cross-species transmission , while the H3N2 subtype represents an important lineage within the swine influenza virus (SIV) family. In this study, a novel reassortant H3N2 SIV strain , designated A/Swine/Jiangsu/YZ07/2024 , was isolated from pigs exhibiting clinical symptoms in Northern Jiangsu , China during epidemiological survey . Genetic analysis revealed that the virus is a complex reassortant, with the internal ...

  Abstract Nipah virus is a highly pathogenic virus in the family Paramyxoviridae that utilizes two distinct surface glycoproteins to infect cells . The receptor-binding protein (RBP) binds host receptors whereas the fusion protein (F) merges viral and host membranes . Here, we use nonreplicative pseudoviruses to safely measure the effects of all F single amino acid residue mutations on its cell entry function and neutralization by monoclonal antibodies . We compare mutational tolerance in F with previous experimental measurements for RBP and show that F is much more functionally constrained than the RBP . We also identify mutationally intolerant sites on the F trimer surface and core that are critical for proper function, and describe mutations that are candidates for stabilizing F in the prefusion conformation for vaccine design . We quantify how F mutations affect neutralization by six monoclonal antibodies, and show that the magnitude of mutational effects on neutralization var...

  Abstract Mpox, caused by the monkeypox virus (MPXV; Orthopoxvirus monkeypox), is on the rise in West and Central Africa . African rodents , especially squirrels , are suspected to be involved in MPXV emergence , but no evidence of a direct transmission to humans or non-human primates has been established. Here we describe an outbreak of MPXV in a group of wild sooty mangabeys (Cercocebus atys) in Taï National Park (Côte d’Ivoire). The outbreak affected one-third of the group, killing four infants . To track its origin, we analysed rodents and wildlife carcasses from the region. We identified a MPXV-infected fire-footed rope squirrel (Funisciurus pyrropus), found dead 3 km from the mangabey territory 12 weeks before the outbreak. MPXV genomes from the squirrel and the mangabey were nearly identical. A video record from 2014 showed a mangabey from this group eating the same squirrel species and diet metabarcoding of faecal samples collected from mangabeys before the outbreak identi...

  Abstract SARS-CoV-2 infections in children occasionally manifest with severe neurologic signs . We report a case series of life-threatening encephalopathy associated with SARS-CoV-2 in 25 children in Australia, Japan, Singapore, and Taiwan during February 2022–January 2024. All children had severe encephalopathy develop, characterized by rapidly progressive cerebral edema , conditions known as acute shock with encephalopathy and multiorgan failure or acute fulminant cerebral edema . Among the 25 patients, 22 (88%) eventually died ; 11 (44%) children died within 24 hours of hospitalization. In addition, 18 (72%) had illness manifest with shock, and 14 (56%) had multiorgan failure develop within 6 hours of neurologic onset. Serum concentrations of cytokines/chemokines including interleukin 6 and tumor necrosis factor-α were significantly higher within 24 hours of onset than for controls. SARS-CoV-2–associated encephalopathy cases such as those described here represent an emerging n...

  Abstract Background   Seasonal human influenza viruses can escape from antibody-mediated neutralization when amino acid changes occur in the hemagglutinin protein . Routine surveillance identified circulation of an A(H3N2) virus variant in the Netherlands with amino acid substitutions at hemagglutinin positions 158 and 189 . These amino acid positions were previously responsible for antigenic change of influenza A(H3N2) viruses and potentially lead to escape of this variant from vaccine-mediated immunity .  Aim   To characterize the emergence and antigenic properties of N158K and K189R double substitution virus variants .  Methods   We analyzed the geographical and temporal dynamics of the double-substitution variant using a phylogeographic approach and used hemagglutination inhibition assays and antigenic cartography methods to map its antigenic properties.  Results   A(H3N2) viruses carrying K189R were first detected in Guatemala in June 2024,...

  Summary Background Adult obesity has been linked to specific infections, but evidence across the full spectrum of infectious diseases remains scarce . In this multicohort study with impact modelling, we examined the association between this preventable risk factor and the incidence, hospitalisations, and mortality of 925 bacterial, viral, parasitic, and fungal infectious diseases, and estimated their global and regional attributable impact. Methods We used pooled data from two Finnish cohort studies and repeated analyses in an independent population from the UK Biobank . BMI was assessed at baseline (1998–2002 in the Finnish studies; 2006–10 in UK Biobank), and participants were categorised as having healthy weight (18·5–24·9 kg/m2), overweight (25·0–29·9 kg/m2) or obesity, classified as class I (30·0–34·9 kg/m2), class II (35·0–39·9 kg/m2), or class III (≥40·0 kg/m2). Participants were followed up through national hospitalisation and mortality registries for hospital admissions ...

  {Summary} In summer 2025, the SARS-CoV-2 JN.1 sublineage became dominant with more resistant variants, such as XFG, LP.8.1, and NB.1.8.1 . COVID-19 mRNA boosters were therefore updated for the 2025–2026 season to target the LP.8.1 spike .1 Previous boosters, particularly the WA1/2020+BA.5 bivalent booster , were characterised by substantial boosting of the ancestral strain , a phenomenon known as immune imprinting .2,3 We therefore evaluated whether the phylogenetically more distant LP.8.1 mRNA booster would preferentially boost currently circulating strains. Recent data from European and Asian populations have reported the immunogenicity of the LP.8.1 mRNA booster .4,5 Herein, we report the immunogenicity of the LP.8.1 mRNA booster in a US population with a different exposure history and high population immunity. We show that the LP.8.1 mRNA booster induced neutralising antibody (NAb) and binding antibody responses, primarily to the vaccine-matched L.P.8.1 variant and other curr...

  Abstract We examined 89 travel-related clade Ib monkeypox virus cases detected in 33 countries during August 2024–July 2025 . Most cases were among men ; about one third led to secondary transmission . Secondary transmission risk was highest among sexual, then household, contacts. Those groups should be the focus of response strategies and interventions. Source:  Link:  https://wwwnc.cdc.gov/eid/article/32/2/25-1530_article ____

  Significance Middle East respiratory syndrome coronavirus (MERS-CoV) remains the most lethal human coronavirus , with continued zoonotic transmission from wild naturally infected dromedary camels , posing a persistent risk of spillover to humans. Despite this ongoing threat , no specific antiviral treatment has been approved. In this study, we characterize the antibody response to MERS-CoV in naturally infected dromedaries, the primary animal reservoir, and identify a panel of nanobodies (Nbs) exhibiting potent neutralizing activity . These Nbs recognize a previously unreported binding and neutralizing site on the virus spike receptor-binding domain (RBD). Their distinctive genetic, structural, and functional properties make them promising candidates for the development of effective and therapeutic interventions against MERS-CoV, as strongly advocated by global health authorities. Abstract Wild dromedary camels in the Arabian Peninsula and Africa have harbored antibodies against ...

  Abstract The outbreak of Highly Pathogenic Avian Influenza H5N1 in U.S. dairy cattle poses substantial risks to public health, economic sustainability of farming, and global food systems . Using a Computable General Equilibrium model , we simulate its short- to medium-term impacts on Gross Domestic Product and other macro-economic outcomes for the US and its main trading partners . We simulate impacts under the current situation and realistic and reasonable worst-case scenarios . We estimate domestic economic losses ranging between 0.06% and 0.9% of US GDP , with losses to the dairy sector ranging between 3.4% and 20.6%. Trading partners increase dairy production to compensate for the loss. Current government subsidies are about 1.2% (95% HDI: 1% to 1.4%) of output losses, and likely insufficient to incentivise farmers to step up surveillance and biosecurity for mitigating the possible emergence of H5N1 strains with pandemic potential into human populations. Source:  Link:...

  Abstract The polymerase acidic (PA) protein is a subunit of the trimeric influenza A virus (IAV) RNA-dependent RNA polymerase and the target of the anti-influenza drug baloxavir marboxil (BXM). As with other direct-acting antivirals , treatment with BXM can lead to selection of viruses carrying resistance mutations . If these mutations have negligible fitness costs, resistant viruses can spread widely and render existing treatments obsolete . Multiple BXM resistance mutations in the nuclease domain of PA have been identified, with I38T and I38M amino acid substitutions occurring frequently. These mutations have minimal to no effects on viral polymerase activity , virus replication , or transmission . However, for reasons that are not well understood, viruses with BXM resistance substitutions have not been able to compete with parental wild-type strains . The IAV genome segment encoding PA also encodes the host shutoff nuclease PA-X, which shares the endonuclease domain with PA bu...

  Highlights •  Randomized trial of 1st and 2nd mRNA SARS-CoV-2 booster vaccination in advanced age •  Higher anti-RBD IgG level and neutralizing capacity with full-dose mRNA-1273 than BNT162b2 •  Decrease in viral neutralization capacity after 12 months against all 25 tested SARS-COV-2 variants •  Oldest population in a SARS-CoV-2 vaccination study (mean 81 yrs) ABSTRACT Background To determine long-term immunogenicity and reactogenicity of different SARS-CoV-2 mRNA-vaccines in a population ≥75 years in a randomized trial. Methods Participants were randomised to receive either BNT162b2 30µg or double booster dose mRNA-1273 , i.e.100µg, as 3rd and 4th vaccination (1st and 2nd booster). Primary endpoint was rate of 2-fold geometric mean titre (GMT) antibody increase 14 days after vaccination targeting the receptor binding domain (RBD) region of wild-type SARS-CoV-2. Secondary endpoints included neutralising capacity against wild-type and 25 variants at 14 days (D...