Characterization of a reassortant #H3N2 swine #influenza virus with 2009 pandemic internal #genes and enhanced potential for zoonotic #risk

 

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 genes (M, NP, PB1, PB2, PA) originated from the 2009 pandemic H1N1 lineage, the NS gene exhibiting a North American triple reassortant origin (human-avian-swine origin), and the HA and NA genes belonging to the human-like lineage. Although neither the rescued virus nor its parental strain could replicate effectively in chicken embryos and chicken cells, both demonstrated efficient replication in mammalian cells, reflected by the much higher polymerase activity in mammalian versus chicken cells. The key residues of HA protein (190D, 225D and 228S) collectively enhanced the binding preference for human-type α-2,6-linked sialic acid receptors, which was confirmed by receptor binding assays. Furthermore, mouse infection experiments using the rescued H3N2 demonstrated efficient viral replication in nasal turbinates and lung tissues, accompanied by significant pulmonary pathological damage. These findings indicate that the YZ07 strain, through the vast reassortment and accumulation of adaptive mutations, has acquired potential zoonotic risk, underscoring the importance of surveillance of swine influenza viruses.

Source: 

Link: https://www.sciencedirect.com/science/article/abs/pii/S0378113526000684?via%3Dihub

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Functional and #antigenic constraints on the #Nipah virus #fusion protein

 

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 varies among antibodies. Our measurements of mutational effects on Nipah virus F predict the ability of the antibodies to neutralize the related Hendra virus. Overall, our work defines the functional and antigenic constraints on the F protein from an important zoonotic virus.

Source: 

Link: https://www.pnas.org/doi/abs/10.1073/pnas.2529505123?af=R

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#Transmission of #Mpox Virus from fire-footed rope #squirrels to sooty #mangabeys

 

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 identified two samples containing fire-footed rope squirrel DNA. One of these samples was also the first positive for MPXV. This represents a rare case of direct detection of interspecies transmission. Our findings indicate that rope squirrels were the source of the MPXV outbreak in mangabeys. Because squirrels and non-human primates are hunted, traded and consumed by humans in West and Central Africa10,11, exposure to these animals probably represents risk for zoonotic transmission of MPXV.

Source: 

Link: https://www.nature.com/articles/s41586-025-10086-y

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Life-Threatening #SARS-CoV-2–Associated #Encephalopathy and Multiorgan Failure in #Children, #Asia and #Oceania, 2022–2024

 

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 neurologic crisis with high mortality rate resulting from rapidly progressive brain edema and multiorgan failure.

Source: 

Link: https://wwwnc.cdc.gov/eid/article/32/2/25-0549_article

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#Poland - High pathogenicity avian #influenza #H5N1 viruses (Inf. with) (#poultry) - Immediate notification

 

A slaughter turkeys operation in Dolnośląskie Region.

Source: 

Link: https://wahis.woah.org/#/in-review/7258

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Emergence and #antigenic characterisation of #influenza #H3N2 viruses with #hemagglutinin substitutions N158K and K189R during the 2024/25 influenza season

 

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, before subsequently gaining the N158K substitution, which was initially detected in Colombia in November 2024, followed by detection in the Netherlands in December 2024. However, detections within Europe remained almost entirely confined to the Netherlands. The proportion of viruses carrying the N158K and K189R substitutions increased to 16% - 24% per collection week of sequenced Dutch viruses during the peak of the epidemic of the 2024-2025 respiratory season. Antigenic characterization of viruses with N158K and K189R substitutions indicated that these are antigenically distinct from the A(H3N2) components of 2025-2026 Northern Hemisphere vaccines, showing 8-192-fold reduction in hemagglutination inhibition titers with antisera against the vaccine strain compared to antisera against the homologous virus. 

Conclusions 

Influenza A(H3N2) viruses with N158K and K189R escaped recognition by antibodies raised against the 2024-2025 and 2025/2026 Northern Hemisphere vaccine strains in hemagglutination inhibition assays. These variants circulated widely in the Netherlands during the 2024-2025 influenza season, raising concerns about reduced vaccine-mediated protection if such variants would spread more broadly during 2025-2026 Northern Hemisphere season.

Competing Interest Statement

The authors have declared no competing interest.

Funder Information Declared

Ministry of Health Welfare and Sport, https://ror.org/041evnj42

Cancer Research UK

Medical Research Council, CC1114

Wellcome Trust, CC1114

National Institute of Allergy and Infectious Diseases (NIAID), R01 AI165692

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.02.10.704996v1

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New contagious #skin #disease detected in #horses in #Sweden (State Veterinary Medical Institute, Feb. 11 '26)

 

A horse in Jönköping County and one in Norrbotten County, both of which had blisters and sores on the skin on their legs, were found to be infected with a smallpox virus called equine parapoxvirus or horse parapoxvirus. It is an infection that has not previously been detected in the country.

The equine parapoxvirus was detected in our neighboring country Finland for the first time in 2021. The State Veterinary Institute, SVA, has performed DNA analysis of the virus in the Swedish cases and it turned out to be the same type as in Finland. The virus has caused outbreaks in several Finnish stables with severe skin inflammation on the horses' legs, so-called mug or rasp.

The typical symptom of parapoxvirus is small blisters (pox) that burst into round sores. The virus is transmitted by direct contact but also via equipment, clothing, hands and objects. Sick horses should be kept isolated from other horses. Use disposable gloves and special clothing when handling.   

– This is a new infection that has probably not yet gained a real foothold in Sweden. We have gone back and analyzed previously submitted skin samples from around 80 horses with skin problems in recent years. However, none of these carried parapoxvirus, says Gittan Gröndahl, state veterinarian at SVA.

Humans can also be infected with the horse parapoxvirus and get blisters/pox and sores on the skin. In Finland, a few horse grooms have had problems, but no human cases were reported from the two Swedish stables with sick horses. If someone gets pox or sores after visiting a sick horse, a doctor should be contacted.

– Our assessment is that the risk of further spread of infection is low at present. However, if there are signs of contagious foot and mouth disease, or if there are blisters or typical round wounds in the horse, virus samples should be taken. Keep in mind the risk of infection, and always use disposable gloves when handling wounds in horses, says Gittan Gröndahl.

Samples from suspected cases can be sent for analysis to SVA.

How is equine parapoxvirus transmitted?

· In direct contact between horses

· Indirectly via equipment, clothing, hands and objects

· People can also get blisters (pox) that burst into sores on the skin.

· There is no vaccine.

Think about hygiene

· Use disposable gloves when handling the horse's wounds, even small wounds.

· Wash your hands thoroughly before and after handling wounds.

· Do not share equipment between horses and stables and be careful with hygiene routines

· Contact a doctor if you develop smallpox or sores on skin that has been in contact with a sick horse.

Source: 

Link: https://www.sva.se/aktuellt/nyhetsarkiv/webbnyheter/ny-smittsam-hudsjukdom-paavisad-hos-haestar-i-sverige/

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Adult #obesity and #risk of severe #infections: a multicohort study with global burden estimates

 

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 and deaths due to infectious diseases. Using hazard ratios derived from the Finnish cohorts and UK Biobank, along with obesity prevalence estimates from the Global Burden of Diseases, Injuries, and Risk Factors Study database, we estimated the proportion of fatal infections attributable to obesity globally, regionally, and by country for the years 2018 (before), 2021 (during), and 2023 (after the COVID-19 pandemic).

Findings

The analysis included 67 766 adults (mean age 42·1 [SD 10·8] years; 49 516 [73·1%] females, 18 250 [26·9%] males) from the Finnish cohorts and 479 498 adults (mean age 57·0 [SD 8·1] years; 261 084 [54·4%] females, 218 414 [45·6%] males) from UK Biobank. Participants had no recent history of infection-related hospitalisations at baseline. During follow-up, there were 8230 incident infection cases in the Finnish cohorts and 81 945 in UK Biobank. Compared with individuals of healthy weight, those with class III obesity had a three-times higher risk of infection-related hospital admissions (Finnish cohorts 2·75 [95% CI 2·24–3·37], UK Biobank 3·07 [2·95–3·19]), death (Finnish cohorts 3·06 [1·25–7·49], UK Biobank 3·54 [3·15–3·98]), or either outcome (Finnish cohorts 2·69 [2·19–3·30], UK Biobank 3·07 [2·95–3·19]). The corresponding pooled hazard ratio for either fatal or non-fatal severe infection among individuals with any obesity (classes I–III) was 1·7 (1·7–1·8). This association was consistent across different indicators of obesity (BMI, waist circumference, and waist-to-height ratio), demographic and clinical subgroups, and a wide range of infections (non-fatal and fatal, acute and chronic, bacterial and viral [including subtypes], and parasitic and fungal). Applying these risk estimates to global burden of disease data, the population attributable fractions of infection-related deaths due to obesity were estimated at 8·6% (6·6–11·1) in 2018, 15·0% (12·8–17·4) in 2021, and 10·8% (8·6–13·6) in 2023.

Interpretation

Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, populations, and baseline clinical profiles, with evidence suggesting that approximately one in ten infection-related deaths worldwide might be attributable to obesity.

Funding

Wellcome Trust, Medical Research Council, and Research Council of Finland.

Source: 

Link: https://www.sciencedirect.com/science/article/pii/S0140673625024742?dgcid=rss_sd_all

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#China reported two additional #human #infections with #influenza A #H9N2 and one new case of #H10N3 (HK CHP, Feb. 10 '26)

 

{Excerpt}

Avian Influenza Report - Reporting period: February 1, 2026 – February 7, 2026 (Week 6) (Published on February 10, 2026) 

-- Avian influenza A(H9N2): 

1) Guangdong Province: 

- A 73-year-old woman with onset on January 17, 2026. 

2) Hunan Province: 

- A 2-year-old boy with onset on December 29, 2025. 

-- Avian influenza A(H10N3):

1) Guangdong Province: 

- A 34-year-old man with onset on December 29, 2025.  

(...)

Source: 

Link: https://www.chp.gov.hk/files/pdf/2026_avian_influenza_report_vol22_wk06.pdf

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Overcoming immune #imprinting with the #COVID19 #LP81 #mRNA #boosters

 

{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 currently circulating variants and lower responses to the ancestral WA1/2020 strain.

(...)

Source: 

Link: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(26)00050-2/fulltext?rss=yes

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Characteristics and #Transmission Dynamics of Global #Travel-Related #Mpox Cases Caused by Clade Ib Monkeypox Virus

 

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

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Decoding #antibody response to #MERS-CoV in wild dromedary #camels

 

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 Middle East Respiratory Syndrome Coronavirus (MERS-CoV) for decades, predating zoonotic spillover to humans. However, the potency, specificity, and structural characteristics of these antibodies remain poorly understood. Here, we characterize the antibody responses of naturally infected wild dromedary camels in Tunisia, a MERS-CoV-endemic region. Plasma antibodies from nine camels exhibited variable neutralizing activity, generally increasing with age, and were largely autologous, with minimal cross-reactivity to SARS-CoV-1 or SARS-CoV-2. From a VHH antibody library derived from the peripheral blood mononuclear cells (PBMCs) of a single camel (D17), we identified 34 unique sequences with previously unreported germline origins and unusually long complementarity-determining region 3 (CDR3) sequences. Eight representative VHHs, expressed as human Fc fusions, displayed high-affinity binding to the MERS-CoV receptor-binding domain (RBD) and broad neutralization to RBD mutants (IC50: 1.05 to 9.55 ng/mL). Crystal structural analysis revealed distinct neutralization mechanisms: VHH-227 fully blocked DPP4 binding, achieving complete neutralization, while VHH-T71, with partial neutralization (~80%), targeted the RBD core subdomain. This study provides comprehensive characterization of wild dromedary antibody responses, identifying novel nanobodies (Nbs) with broad and potent neutralization to naturally occurring RBD mutants. These findings offer insights into camel immunity and highlight promising candidates for MERS-CoV prophylactic and therapeutic development.

Source: 

Link: https://www.pnas.org/doi/10.1073/pnas.2513716123

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An #outbreak of highly pathogenic avian #influenza #H5N1 could impact the dairy #cattle sector and the broader #economy in the #USA

 

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: https://www.nature.com/articles/s43247-025-03153-9

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Impaired #host shutoff is a fitness cost associated with #baloxavir marboxil #resistance #mutations in #influenza A virus PA/PA-X nuclease domain

 

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 but has a unique C-terminal domain generated by ribosomal frameshifting during translation. Unlike their effects on PA activity, the effects of BXM or the I38T/M substitutions on PA-X function remain uncharacterized. In our work, for the first time, we directly examine the effects of baloxavir and the I38T/M substitutions on PA-X activity and show that baloxavir inhibits PA-X activity in a dose dependent manner. Most importantly, we also demonstrate that the I38T/M mutations significantly impair the host shutoff activity of PA-X proteins from different IAV strains of H1N1, H3N2, and H5N1 subtypes. Our work reveals that the deleterious effects of I38T/M on PA-X function may represent an important barrier to the spread of BXM-resistant viruses.

Source: 

Link: https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1013550

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#Poland - High pathogenicity avian #influenza #H5N1 viruses (Inf. with) (#poultry) - Immediate notification

 

A slaughter turkeys farm in Zachodniopomorskie Region.

Source: 

Link: https://wahis.woah.org/#/in-review/7254

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#Iceland - #Influenza A #H5N1 viruses of high pathogenicity (Inf. with) (non-poultry including wild birds) (2017-) - Immediate notification

 

{Whooper Swan}

__

{Eurasian Wigeon}

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A wild Whooper Swan in Höfuðborgarsvæði Region. 

A wild Eurasian Wigeon in Höfuðborgarsvæði Region.

Source: 

Link: https://wahis.woah.org/#/in-review/7248

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Immunogenicity, reactogenicity and #safety to assess #booster #vaccinations with #BNT162b2 or double-dose #mRNA-1273 in adults ≥75 years (EU-COVAT-1-AGED) – final report

 

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 (D14) and 12 months (M12). Safety was assessed by monitoring adverse events (AEs) for seven days after vaccination.

Findings

Between Nov-2021 and Sep-2022, 322 participants received a SARS-CoV-2 vaccine as a 1st (Part A) or 2nd booster (Part B). Primary endpoint results have been published previously. In Part A, it was reached by 100% in both vaccine arms with a higher GMT increase in the mRNA-1273 arm (ratio 1.64). At M12, GMT of anti-RBD IgG was slightly higher than at D14 (9,319.7 vs. 8,568.4IU/mL) in the BNT162b2 arm while in the mRNA-1273 arm, GMT was equal (14,163.8 vs.14,266.7IU/mL at D14.)

In Part B, primary endpoint was reached by 78.5% subjects in the BNT162b2 and 87.2% in the mRNA-1273 arm (p=0.056), respectively, with a higher GMT increase of anti-RBD IgG for mRNA-1273 (ratio 1.38). At M12, GMT of anti-RBD IgG was markedly lower than at D14 (9,962 vs. 15,248.2IU/mL) in the BNT162b2 arm as well as in the mRNA-1273 arm (12,024.3 vs. 21,325.6IU/mL). Higher neutralising capacity in individuals boostered with mRNA-1273 was detected against wild-type and 15/25 tested variants.

Less participants in mRNA-1273 arm had vaccine-related AEs (29.6% vs. 38.5%), but severity was more frequently grade 2 (n=38, 28.1 % vs. 22, 16.3%).

Interpretation

Long-term serological immunogenicity and virus neutralization capacity in subjects ≥75 years was numerically better with a mRNA-1273 100µg booster with comparable safety profile.

Source: 

Link: https://www.ijidonline.com/article/S1201-9712(26)00101-3/fulltext

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Efficient #replication of #influenza D virus in the #human #airway underscores zoonotic potential

 

Abstract

Influenza D virus (IDV), primarily found in livestock species, has demonstrated cross-species transmission potential, yet its threat to humans remains poorly understood. Here, we curated a panel of IDV isolates collected during field surveillance from 2011 to 2020 from swine and cattle to assess their ability to infect human airway cells as a proxy for zoonotic threat assessment. Using lung epithelial cell lines, primary well-differentiated airway epithelial cultures, and precision-cut lung slices, we demonstrated that IDV efficiently propagates in cells and tissues from the human respiratory tract, reaching titers comparable to human influenza A virus (IAV). Infection kinetics in primary porcine airway cultures and respiratory tissues mirrored those from human, suggesting similar infectivity across species. To define host responses to IDV infection, we evaluated innate immune sensing and downstream interferon signaling in human respiratory cells. IDV infection resulted in markedly reduced activation of interferon regulatory factor (IRF) signaling and diminished induction of interferon lambda 1 and interferon-stimulated genes compared to IAV, indicating inefficient activation of innate immune sensing pathways. However, IDV replication was potently restricted in interferon-pretreated cells, demonstrating sensitivity to interferon-mediated antiviral effector mechanisms once an antiviral state was established. Together, these findings show that IDV can efficiently infect the human airway while limiting innate immune sensing, a feature that may facilitate zoonotic spillover. Our study highlights the need for enhanced surveillance of IDV at the animal-human interface and provides a foundation for further investigation into its biology and potential for causing human infection and disease.

Competing Interest Statement

The author E.M.K. is currently employed by AbbVie Inc. The author was not affiliated with AbbVie Inc at the time of experiment design, data acquisition, or analysis.

Funder Information Declared

United States Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA), 2025-39601-44639

The Enterprise for Research, Innovation, and Knowledge at The Ohio State University

Centers of Excellence for Influenza Research and Response, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Department of Health and Human Services, HHSN272201400006C, 75N93021C00016

National Institutes of Health, T35 5T35OD010977

National Institutes of Health, P30 CA016058

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.02.07.704474v1

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The Battlefield, Kathe Kollwitz (1907)

 

Public Domain.

Source: 

Link: https://www.wikiart.org/en/kathe-kollwitz/the-battlefield-1907

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Research Note: Molecular Characteristics and #Genetic #Evolution of #H1N1 Avian #Influenza Virus from Wild #birds in #Shanghai, #China

 

ABSTRACT

The H1N1 influenza virus is a major pandemic and seasonal pathogen with a broad host range, posing a substantial threat to human health and underscoring the need for continuous surveillance. Wild birds, as natural reservoirs of avian influenza viruses (AIVs), carry H1N1 strains capable of reassorting with other influenza viruses, which can drive pandemic emergence. The global migration of wild birds facilitates the spread of these viruses, and their interactions with poultry increase the risk of cross-species transmission, further amplifying the public health threat. However, knowledge of H1N1 genetic diversity in wild birds remains limited. Database analysis shows 80% of avian-origin H1N1 isolates come from wild birds across over 40 countries, mainly in North America, Europe and Asia. This study characterized the molecular traits and genetic evolution of four H1N1 AIVs isolated from common teal and spot-billed ducks during 2019–2021. Phylogenetic and sequence analyses revealed these viruses cluster into distinct lineages, divergent from mammalian H1N1 strains, with complex genetic origins involving frequent recombination and high diversity. Frequent wild bird–poultry transmission elevates zoonotic risks. Our findings highlight wild birds’ critical role in H1N1 transmission and confirm their role as an H1N1 gene pool, emphasizing the need for sustained monitoring and research.

Source: 

Link: https://doi.org/10.1016/j.psj.2026.106580

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