Avian #Influenza #H9N2 - #Italy (#WHO, D.O.N., April 10 2026)

 

Situation at a glance

-- On 21 March 2026, the National International Health Regulations (IHR) Focal Point for Italy notified the World Health Organization (WHO) of the identification of a human case of avian influenza A(H9) in an adult male returning from Senegal. 

- Next generation sequencing confirmed Influenza A(H9N2). 

- According to epidemiological investigations, the patient had no known history of exposure to poultry or any person with similar symptoms prior to the onset of symptoms. 

- Authorities in Italy have implemented a series of measures aimed at monitoring, preventing and controlling the situation. 

- According to the IHR (2005), a human infection caused by a novel influenza A virus subtype is an event that has the potential for high public health impact and must be notified to the WHO. 

- This is the first imported human case of avian Influenza A(H9N2) reported in the European Region. 

- Based on currently available information, WHO assesses the current risk to the general population posed by A(H9N2) viruses as low but continues to monitor these viruses and the situation globally.

Description of the situation

-- On 21 March 2026, the National IHR Focal Point for Italy notified WHO of the identification of a human case of avian influenza A(H9) in an adult male.

-- The patient had been in Senegal for more than six months and traveled to Italy in mid-March. Upon arrival, he visited the emergency department with a fever and a persistent cough.

-- On 16 March, a bronchoalveolar lavage specimen was collected, which showed a positive Mycobacterium tuberculosis result, as well as detection of un-subtypeable influenza A virus. The patient was placed in a negative-pressure isolation room with airborne precautions. He was treated with antitubercular medication and antiviral oseltamivir. By 9 April, his condition was stable and improving.

-- On 20 March, a regional reference laboratory identified the A(H9) subtype, and on 21 March, next-generation sequencing confirmed influenza A(H9N2). Initial genetic findings suggest the infection was likely acquired from an avian source linked to Senegal. Additional samples have been sent to Italy’s National Influenza Center, where further characterization confirmed virus subtype Influenza A(H9N2), with close genetic similarity to strains previously identified in poultry in Senegal.

-- No direct exposure to animals, wildlife or rural environments was identified. There was also no reported contact with symptomatic or confirmed human cases. Further epidemiological investigations on the source of exposure are ongoing.

-- Contacts identified in Senegal were asymptomatic. All identified and traced contacts in Italy have tested negative for influenza and completed the period of active monitoring for the onset of symptoms and the quarantine required by national guidelines. They also received oseltamivir as a preventive measure. 

Epidemiology

-- Animal influenza viruses normally circulate in animals but can also infect people. Infections in humans have primarily been acquired through direct contact with infected animals or through indirect contact with contaminated environments. Depending on the original host, influenza A viruses can be classified as avian influenza, swine influenza, or other types of animal influenza viruses.

-- Avian influenza virus infections in humans may cause diseases ranging from mild upper respiratory tract infection to more severe diseases and can be fatal. Conjunctivitis, gastrointestinal symptoms, encephalitis and encephalopathy have also been reported.

-- Laboratory tests are required to diagnose human infection with influenza. WHO periodically updates technical guidance protocols for the detection of zoonotic influenza using molecular methods. 

-- Human infections with influenza A(H9) viruses have been reported from countries in Africa and Asia, where these viruses are also detected in poultry. The majority of cases of human avian influenza A(H9N2) infection have been reported from China. This is the first imported human case of avian Influenza A(H9N2) virus infection reported in the European Region. 

Public health response

-- Contact tracing procedures have been initiated, and relevant authorities in Italy, as well as internationally (National IHR Focal Point for Senegal, WHO, and European Centre for Disease Prevention and Control (ECDC)) have been informed through IHR channels. Once avian influenza was suspected, the response moved quickly from hospital-level management to regional laboratory confirmation and national coordination. Additionally, the regional surveillance system was notified, integrated within the One Health avian influenza reporting framework.

WHO risk assessment

-- Most reported human cases of A(H9N2) virus infection have been linked to exposure to infected poultry or contaminated environments, with the majority of cases experiencing mild clinical illness. Sporadic human cases following exposure to infected birds or contaminated environments can be expected since the virus remains enzootic in poultry populations. Avian influenza A(H9N2) viruses have been detected in poultry and environmental samples collected at live bird markets in Senegal and authorities in the country reported a human case of infection with an A(H9N2) virus in 2020.

-- Current epidemiological and virological evidence indicates that none of the characterized influenza A(H9N2) viruses thus far have acquired the ability for sustained transmission among humans. Thus, the likelihood of sustained human-to-human spread is low at this time. Infected individuals traveling internationally from affected areas may be identified in another country during or after arrival. However, if this were to occur, further community-level spread is considered unlikely. The risk assessment would be revisited if and when further epidemiological and virological information becomes available.

WHO advice

-- This case does not change the current WHO recommendations on public health measures and surveillance of influenza.

-- The public should avoid contact with high-risk environments such as live animal markets/farms or surfaces that might be contaminated by poultry feces. Respiratory protection is highly recommended for those handling live or dead (including slaughtering) poultry in occupational or backyard-farming settings. Good hand hygiene, i.e. frequent washing of hands or the use of alcohol-based hand sanitizer is recommended. WHO does not recommend any specific additional measures for travelers.

-- Under Article 6 of the IHR, all human infections caused by a new subtype of influenza virus are notifiable. The case definition for notification of human influenza infection caused by a new subtype under the IHR is provided here. State Parties to the IHR are required to immediately notify WHO of any laboratory-confirmed case of a human infection caused by such an influenza A virus.

-- WHO advises against the application of any travel or trade restrictions based on the current information available on this event. 

Further information

-- WHO fact sheet on Influenza (avian and other zoonotic): https://www.who.int/news-room/fact-sheets/detail/influenza-(avian-and-other-zoonotic)

-- WHO Global influenza programme, human-animal interface: https://www.who.int/teams/global-influenza-programme/avian-influenza

-- WHO Monthly Risk Assessment Summary: Influenza at the human-animal interface: https://www.who.int/teams/global-influenza-programme/avian-influenza/monthly-risk-assessment-summary

-- Protocol to investigate non-seasonal influenza and other emerging acute respiratory diseases: https://www.who.int/publications-detail-redirect/WHO-WHE-IHM-GIP-2018.2

-- World Health Organization. Public health resource pack for countries experiencing outbreaks of influenza in animals: revised guidance: https://www.who.int/publications/i/item/9789240076884

-- Implementing the integrated sentinel surveillance of influenza and other respiratory viruses of epidemic and pandemic potential by the Global Influenza Surveillance and Response System: https://www.who.int/publications/i/item/9789240101432

-- Case definitions for the four diseases requiring notification in all circumstances under the International Health Regulations (2005): https://www.who.int/publications/m/item/case-definitions-for-the-four-diseases-requiring-notification-to-who-in-all-circumstances-under-the-ihr-(2005)

-- Mosaic Respiratory Surveillance Framework: https://www.who.int/initiatives/mosaic-respiratory-surveillance-framework/

-- Practical interim guidance to reduce the risk of infection in people exposed to avian influenza viruses: https://www.who.int/publications/i/item/B09116

-- Antigenic and molecular characterization of low pathogenic avian influenza A(H9N2) viruses in sub-Saharan Africa from 2017 through 2019: https://hal.inrae.fr/hal-03213105v1

-- Genetic and Molecular Characterization of Avian Influenza A(H9N2) Viruses from Live Bird Markets (LBM) in Senegal: https://doi.org/10.3390/v17010073

-- Genetic characterization of the first detected human case of low pathogenic avian influenza A/H9N2 in sub-Saharan Africa, Senegal: https://doi.org/10.1080/22221751.2020.1763858

-- ECDC. First human case of influenza A(H9N2) infection imported in the EU: https://www.ecdc.europa.eu/en/news-events/first-human-case-influenza-ah9n2-infection-imported-eu

-- Ministry of Health, Italy. Influenza A (H9N2) virus case identified in Lombardy. Routine surveillance and prevention procedures activated: https://www.salute.gov.it/new/it/comunicato-stampa/virus-influenzale-h9n2-identificato-caso-lombardia-attivate-le-ordinarie/

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Citable reference: World Health Organization (10 April 2026). Disease Outbreak News: Avian Influenza A(H9N2) in Italy. Available at: https://www/who.int/emergencies/disease-outbreak-news/item/2026-DON597

Source: 

Link: https://www.who.int/emergencies/disease-outbreak-news/item/2026-DON597

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#USA, #Wastewater Data for Avian #Influenza #H5 (#CDC, April 10 '26, summary)

 

{Excerpt}

(...)

Time Period: March 29, 2026 - April 04, 2026

-- A(H5) Detection: 7 site(s) (1.6%)

-- No Detection: 430 site(s) (98.4%)

-- No samples: 125 site(s)

(...)

Source: 

Link: https://www.cdc.gov/wastewater/emerging-viruses/h5.html

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#USA, Weekly #US #Influenza #Surveillance #Report: Key Updates for Week 13, ending April 4, 2026 (#CDC, summary)

 

(...)

Key Points

-- Seasonal influenza activity continues to decrease in most areas of the country. 

- Influenza A activity is low across all HHS regions while the amount of and trends in influenza B activity vary by region.

-- Influenza A(H3N2) viruses are the most frequently reported influenza viruses overall this season.

-- Among 2,166 influenza A(H3N2) viruses collected since September 28, 2025, that underwent additional genetic characterization at CDC, 92.8% belonged to subclade K.

-- The cumulative influenza-associated hospitalization rate overall in FluSurv-NET is the third highest since the 2010-2011 season. 

- Children younger than 18 years have the second highest cumulative hospitalization rate for that age group since the 2010-2011 season.

-- Twelve influenza-associated pediatric deaths occurring during the 2025-2026 season were reported to CDC this week, bringing the season total to 139 reported influenza-associated pediatric deaths.

-- Among children who were eligible for influenza vaccination and with known vaccination status, approximately 85% of reported pediatric deaths this season have occurred in children who were not fully vaccinated against influenza.

-- CDC's in-season severity assessment framework classified the season as moderate across all ages. 

- CDC also assesses severity by three age groups: pediatric (0-17 years), adult (18-64 years), and older adults (≥65 years). 

- At this point in the season, the pediatric age group is classified as having high severity, while both the adult and older adult age groups are classified as having moderate severity. 

- These assessments are conducted each week during the season, and the season's severity assessment can change if activity should increase again.

-- CDC estimates that there have been at least 31 million illnesses, 370,000 hospitalizations, and 23,000 deaths from flu so far this season.

-- Influenza (flu) vaccination has been shown to reduce the risk of flu and its potentially serious complications. 

- There is still time to get vaccinated against flu this season. 

- Approximately 135 million doses of influenza vaccine have been distributed in the United States this season.

-- There are prescription flu antiviral drugs that can treat flu illness; those should be started as early as possible and are especially important for patients at higher risk for flu-related complications.1

-- Influenza viruses are among several viruses contributing to respiratory disease activity. CDC provides updated, integrated information about COVID-19, flu, and respiratory syncytial virus (RSV) activity on a weekly basis.

-- No new avian influenza A(H5) infections were reported to CDC this week. To date, person-to-person transmission of influenza A(H5) viruses has not been identified in the United States.

(...)

Source: 

Link: https://www.cdc.gov/fluview/surveillance/2026-week-13.html

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#Investigation and #impact of mammalian #adaptation markers on #H5N8 high pathogenicity avian #influenza #polymerase activity

 

Abstract

Highly pathogenic H5Nx viruses of clade 2.3.4.4b have spread worldwide, causing major economic losses and increased human exposure. Since 2020, multiple mammalian infections have been reported, raising concerns about further adaptation to mammalian hosts. We analyzed influenza A virus sequences from the Influenza Virus Database at the National Center for Biotechnology Information to identify new mammalian adaptation markers in the polymerase complex and nucleoprotein, using recursive partitioning. These markers were grouped into “proteotypes” to assess their co-occurrence and association with host origin. This analysis revealed distinct groups of proteotypes linked to mammalian adaptation, including those seen in historical and pandemic human strains. Identified mutations were introduced alone or in combination into a 2.3.4.4b H5N8 virus to evaluate their impact on polymerase activity in mammalian cells using a minigenome assay. PB1 V336I and PB2 K702R increased polymerase activity in human cells, particularly with PB2 E627K, supporting enhanced surveillance of 2.3.4.4b H5Nx viruses. These findings highlight mutation combinations relevant for enhanced surveillance of 2.3.4.4b H5Nx viruses.

Source: 

Link: https://www.nature.com/articles/s44298-026-00188-3

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Easily Scalable, Rapidly Deployable Mechanical Ventilator for Pandemic Health Crises in Resource-Limited Areas

 

Abstract

Background: 

The COVID-19 pandemic exposed critical shortages of mechanical ventilators, particularly in low-resource settings. Disruptions in global supply chains and dependence on specialized components highlighted the need for scalable, locally manufacturing alternatives for emergency respiratory support. 

Aim: 

To describe and evaluate a simplified, supply-chain-independent mechanical ventilator assembled from widely available automotive and simple hardware components, and intended as a last-resort solution. 

Methods: 

The ventilator is based on a reciprocating air pump driven by an automotive windshield wiper motor coupled to parallel shaft bellows and readily assembled passive membrane valves, only requiring materials available from standard hardware retailers, minimal tools, and basic manual skills. Ventilator performance was assessed through bench testing using a patient model simulating severe lung disease in an adult (R=20 cmH2O*s/L, C=15 mL/cmH2O) and pediatric (R=50 cmH2O*s/L, C=10 mL/cmH2O) patients. Realistic proof of concept was performed in four mechanically ventilated 50-kg pigs. 

Results: 

The device delivered tidal volumes up to 600 mL and respiratory rates up to 45 breaths/min with PEEP up to 10 cmH₂O, covering pediatric and adult ventilation ranges. In vivo testing showed that the ventilator maintained arterial blood gases within the targeted range. Technical details for ventilator construction are provided in an open-source video tutorial. 

Discussion: 

This low-cost ventilator demonstrated adequate performance under demanding conditions. Although not a substitute for commercial intensive care ventilators, its simplicity, autonomy, and independence from fragile supply chains provide a potentially life-saving option in resource-constrained emergency scenarios.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

This work was partially supported by Sociedad Espanola de Neumologia y Cirugia Toracica (SEPAR) (grant 1381-2022). SEPAR had no involvement other than providing funding for the independently submitted research project.

Source: 

Link: https://www.medrxiv.org/content/10.64898/2026.04.08.26350386v1

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#Species - and #variant - specific #ACE2 compatibility shapes #SARS-CoV-2 #spillover potential in North American #cervids

 

Abstract

Free-ranging white-tailed deer (WTD) are established SARS-CoV-2 reservoirs, but the susceptibility of other cervid species remains unclear. Here we integrate receptor analysis, structural modeling, and field surveillance to assess SARS-CoV-2 susceptibility across North American cervids. We identify species- and variant-specific differences in ACE2–spike compatibility. Elk ACE2 exhibits weak binding to the ancestral strain (Wuhan-Hu-1) and Delta spike receptor-binding domains (RBDs), likely due to a unique K31N substitution. In contrast, it shows stronger binding to Alpha, Beta, Gamma, and Omicron RBDs containing N501Y. Biophysical assays, gel filtration chromatography, and cryo-EM confirm stable complex formation between elk ACE2 and Alpha RBD, but not RBD from the ancestral strain. Despite weak binding, elk ACE2 supports viral entry and replication in vitro. However, surveillance revealed limited evidence of infection in the United States, contrasting with widespread WTD transmissions. These findings demonstrate that ACE2 compatibility alone is insufficient to predict reservoir potential and provide a framework for assessing species susceptibility to emerging coronaviruses.

Source: 

Link: https://www.nature.com/articles/s41467-026-71623-5

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

{A Canada Goose}

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{A Greylag Goose}

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A wild Greylag Goose and a wild Canada Goose in Innlandet and Østfold Regions.

Source: 

Link: https://wahis.woah.org/#/in-review/7424

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#Preclinical evaluation of an #mRNA #vaccine developed from the first #human isolate of #bovine #H5N1

 

Highlights

• SM102 and DB-Y ionizable lipids deliver H5 mRNA vaccine with high efficiency and safety

• Vaccine-induced antibody and T cell response protect mice from H5N1 challenge

• Pre-existing H1 immunity does not diminish H5-specific immunogenicity

• Vaccine fully protects chicken against clade 2.3.4.4b/h H5 virus challenge

Summary

Given the global threat posed by H5N1 clade 2.3.4.4b avian influenza, rapid development of effective vaccines is imperative. We design an mRNA vaccine encoding hemagglutinin (HA) from A/Texas/37/2024, the first bovine-to-human strain. In murine models, both wild-type and cleavage-site-modified HA vaccines elicit robust and durable humoral immunity, along with a balanced Th1/Th2 response, conferring complete protection against lethal homologous viral challenge. The vaccine, along with the World Health Organization (WHO)-recommended candidate (A/Astrakhan/3212/2020), elicits cross-clade binding antibody responses and demonstrates improvement against specific clades at a 1 μg dose. Pre-existing H1 immunity does not diminish H5-specific immunogenicity. In avian species, the vaccine also provides full protection against lethal clades (2.3.4.4b and 2.3.4.4h). Formulated with another ionizable lipid, the vaccine elicits responses comparable to benchmark lipid nanoparticles (LNPs) and shows a favorable safety profile in rats. This work establishes a rapidly adaptable mRNA-LNP vaccine prototype for pandemic preparedness against evolving avian influenza threats.

Source: 

Link: https://www.cell.com/cell-reports-medicine/fulltext/S2666-3791(26)00119-9?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2666379126001199%3Fshowall%3Dtrue

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#Birth #imprinting effects on the #antibody responses of #H7N9 patients from 2013-2018 in #China

 

Abstract

Background

There is an urgent need to understand the immune correlates of protection against avian influenza viruses (AIV), where pre-existing immunity may be limited.

Methods

Here, we characterized the antibody response in 12 severely ill A(H7N9) patients and examined its association with early-life imprinting and clinical outcome.

Results

We find that A(H7N9) patients imprinted with A(H2N2) during early life show minimal H7-IgM and a rapid IgG response across diverse hemagglutinin subtypes. They also have more high avidity H7-antibodies compared to older or younger patients. Early antibody titers against seasonal H1, H3, and conserved stalk domains trend negatively with clinical severity in A(H7N9) infection, while an inverse pattern is observed following severe A(H1N1) infection, potentially suggesting a different mechanism of immune regulation between seasonal and avian influenza virus infections.

Conclusions

These data provide direct serological evidence that birth imprinting profoundly shapes the humoral immune landscape during zoonotic influenza infection and may influence subsequent disease outcome.

Source: 

Link: https://www.nature.com/articles/s43856-026-01554-1

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Genetic characterization of a novel triple - #reassortant #influenza #H1N2 virus from #pigs, #China, 2021

 

Abstract

Swine influenza virus (SIV) is a highly contagious respiratory pathogen in pigs, with bidirectional transmission posing a potential threat to human health. In this study, nasal swab samples were collected from pigs in Shandong Province, China, and yielded an H1N2 SIV strain, designated A/swine/Shandong/QD726/2021 (H1N2). Whole-genome sequencing was performed for Sw/SD/QD726/2021, and phylogenetic analysis was conducted together with 156 Chinese H1N2 reference sequences obtained from the Global Initiative on Sharing All Influenza Data (GISAID) database and the National Center for Biotechnology Information (NCBI) Influenza Virus Resource database. The results indicated that Sw/QD726/2021 represents a novel reassortant genotype (G21), with the HA gene derived from Eurasian avian-like H1N1 (EA H1N1), the NA and NS genes from triple-reassortant H1N2 (TR H1N2), and the remaining internal genes (PB2, PB1, PA, NP, M) from the 2009 pandemic H1N1 (pdm/09 H1N1). Key amino acid analysis revealed N31 in M2, responsible for adamantane resistance, and S42 in NS1, which influences viral virulence in mouse models. BALB/c mouse experiments demonstrated efficient viral replication in the lungs and nasal turbinates, accompanied by moderate body weight loss and lung lesions, indicating only moderate pathogenicity. These findings underscore the ongoing evolution of H1N2 SIV in pigs and emphasize the importance of enhanced surveillance and preventive strategies to mitigate public health risks.

Source: 

Link: https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2026.1779293/full

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Avian #Influenza #Report - From March 29 to April 4, 2026 (Wk 14) (#HK PRC SAR CHP, April 8 '26): 1 #H5N1 case in #Cambodia, 1 #H7H7 case in #Taiwan

{Excerpts}

(...)

1) H5N1

-- Date of report: 31/03/2026 

-- Country: Cambodia 

-- Province / Region: Oddar Meanchey province

-- District / City: Banteay Ampil district 

-- Sex: Male

-- Age: 3 

-- Condition at time of reporting: Hospitalised 

-- Subtype of virus  H5N1 

(...)

2) H7N7

-- Place of occurrence: Taiwan, China

-- No. of cases  (No. of deaths): 1(0)

-- Details:   

- Avian influenza A(H7N7): 

* Central Taiwan: A man in his 70s who works in a poultry farm with onset on March 20, 2026. 

* This is the first locally-acquired human case of avian influenza A(H7N7) reported in Taiwan, China. 

(...)

Source: 

Link: https://www.chp.gov.hk/files/pdf/2026_avian_influenza_report_vol22_wk14.pdf

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

All [Backyard] birds at the site were culled; surveillance measures continue in the control zone. [Region: Libertador General Bernardo O'Higgins]

Source: 

Link: https://wahis.woah.org/#/in-review/7400

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#Genetic and #biological characterization of a #duck-origin clade 2.3.4.4b #H5N6 avian #influenza virus reveals partial #mammalian #adaptation

 

Highlights

• Duck-origin H5N6 virus A/Duck/Jiangsu/628/2022 shares high homology with the human strain A/Yangzhou/125/2022.

• The 628 strain shows mammalian adaptation markers: HA mutations enhance human receptors affinity and NA mutations reduce sensitivity to neuraminidase inhibitors.

• Limited airborne transmission but detectable droplet-mediated spread suggests increased mammalian transmission risk.

Abstract

Clade 2.3.4.4b H5Nx highly pathogenic avian influenza viruses (HPAIVs) have caused extensive outbreaks in poultry worldwide. H5 HPAIVs have caused sporadic but severe human infections in China, representing a persistent zoonotic threat. Here, we identified a duck-origin H5N6 HPAIV (A/Duck/Jiangsu/628/2022) through routine surveillance and assessed its biological characteristics and mammalian pathogenesis. Phylogenetic analysis revealed > 98% nucleotide identity between strain 628 and the concurrent human H5N6 strain A/Yangzhou/125/2022. Molecular characterization identified multiple mammalian adaptation markers: hemagglutinin substitutions (S137A, T160A, T192I) associated with enhanced human receptor binding; neuraminidase mutations (I117T, D198N) linked to reduced neuraminidase inhibitor susceptibility; and polymerase complex changes (PB1-D622G, PA-K142Q) conferring increased mammalian cell replication. In vitro studies demonstrated that 628 virus replicated more efficiently in mammalian than in avian cells and exhibited dual receptor-binding specificity. Mouse pathogenicity assays revealed moderate virulence with progressive lung pathology. Critically, transmission experiments confirmed both direct contact and airborne transmission capabilities of 628 in guinea pigs. These findings demonstrate that circulating H5N6 viruses have acquired partial mammalian adaptation while retaining avian fitness, significantly elevating pandemic potential. Enhanced surveillance of wild bird populations, poultry farms, and live poultry markets is urgently needed to develop effective prevention and control strategies.

Source: 

Link: https://www.sciencedirect.com/science/article/abs/pii/S037811352600146X?via%3Dihub

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Using an evolutionary epidemiological #model of #pandemics to estimate the #infection #fatality ratio for #humans infected with avian #influenza viruses

 

Abstract

The risk of highly pathogenic avian influenza virus infection to humans is challenging to estimate as many human avian influenza virus (AIV) infections are undetected because infections may be asymptomatic, symptomatic but not tested, and difficult to identify through contact tracing, as human-to-human transmission is rare. We derive equations that consider the evolutionary mechanisms that give rise to pandemics and are parameterized to be consistent with records of past pandemics. We estimate that thousands of human AIV infections occur worldwide in an average year and estimate the infection fatality ratio as 32 deaths per 10,000 infections (95% confidence interval: [9.6, 75]). This estimate is comparable to SARS-CoV-2 during the recent pandemic and higher than seasonal human influenza. We estimate that preventing animal-to-human influenza spillovers would delay pandemic emergence by several years. Preventing human infections with AIV is necessary given the high risk of severe outcomes to individuals and to reduce the risk of pandemics occurring in the future.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

AH was supported by a Natural Sciences and Engineering Research Council of Canada Discovery Grant (RGPIN 023-05905) and a Catalyst Grant: Avian Influenza OneHealth Research, Enhanced tracking of the circulation of and risk from highly pathogenic avian influenza viruses at the human-wildlife interface from the Canadian Institutes of Health Research. JM, ML, and AH were support by an Atlantic Canada Research in the Mathematical Sciences Collaborative Research Group award.

Source: 

Link: https://www.medrxiv.org/content/10.64898/2026.01.21.26344526v2

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#Genomic characterisation of Crimean-Congo haemorrhagic fever virus (#CCHFV) in #Tajikistan identifies a novel reassortant virus

 

Abstract

Crimean-Congo haemorrhagic fever virus (CCHFV) is an important human tick-borne pathogen, able to cause severe haemorrhagic fever. CCHFV is endemic in Tajikistan, which records between 5–38 cases of CCHF a year from southern regions. Molecular surveillance of CCHFV is crucial to implement effective prevention and control strategies, understand viral evolution, study transmission dynamics, and develop effective diagnostics, therapeutics, and vaccines. While the presence of Asia-1 and Asia-2 genotypes has been previously reported, only two historical samples from Tajikistan have been fully sequenced. In this study we developed and applied a genotype IV-specific tiling PCR enrichment approach recovering 52 CCHFV genome segment sequences from clinical and Hyalomma tick samples collected between 2017–2023. Most sequences belonged to the Asia-2 genotype, but one virus exhibited an Asia-1 S segment combined with Asia-2 M and L segments, representing the first evidence of such viral reassortment event in Tajikistan.

Source: 

Link: https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0014204

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Deep #disadvantage in #mortality on the frontlines of the #COVID19 #pandemic

 

Abstract

This study presents new evidence on the temporal and spatial impact of the COVID-19 pandemic on mortality among especially vulnerable New Yorkers. Using burial records from Hart Island—the City’s potter’s field—we study the distribution of unclaimed deaths over time and across boroughs in 2020 compared to pre-pandemic levels. We show that the Hart Island deaths began deviating from their historical pattern in early March 2020 and peaked five weeks later at 22 deaths for every death in the same week in 2019 (20:1 adjusted). COVID-19 excess death rates were more than twice as high in the Bronx compared to other boroughs. Citywide, we estimate that 10% of all COVID-related excess deaths during the initial outbreak (March–August 2020) were unclaimed. These findings suggest the pandemic greatly magnified existing inequalities in the City and, more broadly, illustrate the especially devastating impact of COVID-19 on economically and socially vulnerable populations.

Source: 

Link: https://www.nature.com/articles/s41598-026-41219-6

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

 

A wild Greylag Goose in Kalmyk Region.

Source: 

Link: https://wahis.woah.org/#/in-review/7410

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MF59-adjuvanted A/Astrakhan #influenza #vaccine induces cross-neutralizing #H5N1 #antibodies in #ferrets against circulating clade 2.3.4.4b viruses

 

Abstract

The continued global spread of highly pathogenic avian influenza A(H5N1) viruses, particularly clade 2.3.4.4b, has increased zoonotic spillover risk and underscored the urgency of pandemic preparedness. Human vaccination is a key strategy for mitigating severe disease and limiting transmission, especially in a setting where avian influenza viruses pose a zoonotic threat. We evaluated the immunogenicity of the MF59-adjuvanted, egg-derived A/Astrakhan/3212/2020 (H5N8) influenza vaccine (CBER-RG8A) in ferrets. To assess cross-reactivity, we generated pseudoviruses bearing HA and NA from circulating A(H5N1) 2.3.4.4b viruses, including North American (B1.13 and D1.1) and Eurasian (DI.2) genotypes. Immunogenicity was assessed using hemagglutination inhibition and microneutralization assays. A single dose elicited robust neutralizing titers (GMT ≥ 160), while a second dose increased titers by ≥3.3-fold. Cross-reactivity was maintained across most strains; however, responses were reduced up to 8-fold against strains harboring the A156T HA mutation, which may introduce a glycosylation site at antigenic site B. Limited responses were detected against divergent clades, with modest titers against clade 2.3.2.1a. These findings suggest broad protection induced by the CSL Seqirus pandemic vaccine against contemporary clade 2.3.4.4b A(H5N1) viruses and underscore the value of ferret immunogenicity data in informing strain selection and regulatory preparedness when human clinical data are unavailable.

Source: 

Link: https://www.nature.com/articles/s41541-026-01438-4

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#Genomic analysis of high pathogenicity avian #influenza viruses from #Antarctica reveals multiple introductions from South #America

 

Abstract

The spread of high pathogenic avian influenza virus (HPAIV) H5N1 clade 2.3.4.4b into Antarctica poses a major threat to polar wildlife. We report the detection of H5N1 in carcasses of eight species during the 2023-2024 and 2024-2025 austral summers in the South Shetland Islands: Antarctic shag, Antarctic tern, kelp gull, pintado petrel, Antarctic petrel, skuas, Antarctic fur seal, and southern elephant seal. Whole-genome sequencing, mutational profiling, and phylogenetic reconstruction revealed that the viruses detected in these hosts descended from distinct introduction events. One group of strains including complete and partial viral genomes from a gull, skuas, fur seals, an Antarctic tern, and a southern elephant seal clustered with H5N1 strains previously detected in marine mammals in South America and formed a polyphyletic lineage consistent with at least two independent introductions into Antarctica. A second group of strains including complete and partial viral genomes from petrels, shags, and skuas clustered with H5N1 strains previously detected in seabirds and marine mammals in South Georgia and with a previously reported HPAIV detection from Torgersen Island, Antarctic Peninsula. These findings reveal extensive epidemiological connectivity between South America and Antarctica, with South Georgia serving as a “stepping stone” for virus spread in the region.

Source: 

Link: https://www.nature.com/articles/s41467-026-71544-3

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#USA, DOH and #CDC Investigate Invasive Group A Streptococcal (#IGAS) Infections in West #Hawaii (April 7 '26)

 

HONOLULU — The Hawaiʻi Department of Health (DOH) and Hawaiʻi District Health Office are working with the Centers for Disease Control and Prevention (CDC) to investigate a report of high rates of a serious bacterial infection called invasive Group A Streptococcus (iGAS) in West Hawaiʻi.

This investigation began after a local physician identified a higher-than-expected number of patients with iGAS over a period of several months and informed DOH. 

While DOH routinely monitors these infections, historically Hawaiʻi has had higher rates than the national average. 

This investigation will help determine whether the number of people with iGAS is increasing in West Hawaiʻi and better understand possible causes and risk factors of this infection.

The goals of this investigation are to confirm whether there is an increase in the number of people with iGAS in West Hawaiʻi, identify risk factors, evaluate disease reporting, and better understand how infections may be occurring in the community. 

Investigators will also compare local trends with other areas of the state and analyze laboratory data to identify any patterns among people with iGAS infections.

Group A Streptococcus bacteria are commonly found on the skin or in the throat and often do not cause an infection. 

When infections do occur, they are usually mild illnesses such as strep throat or skin infection. 

In rare cases, the bacteria can enter the bloodstream or other normally sterile parts of the body. This is called invasive Group A Streptococcus (iGAS), which can be serious. Early treatment with antibiotics is effective, especially when care is given promptly.

Some people are at higher risk for severe illness. These include older adults and individuals with chronic medical conditions such as heart, kidney, or respiratory disease and diabetes. People with weakened immune systems, those with open wounds or skin infections — and people experiencing homelessness or who inject drugs may also be at increased risk. 

In addition, recent viral infections such as influenza or chickenpox can increase one’s risk. The specific causes of the elevated iGAS illnesses in West Hawaiʻi are not yet known, so DOH and CDC are investigating.

DOH encourages the public to take simple steps to reduce the risk of infection. 

- Keep cuts and wounds clean and covered until they heal and 

- wash hands regularly with soap and water. 

- Seek medical care if a wound becomes red, swollen, warm, or produces pus. 

- Anyone experiencing fever, severe pain, or rapidly worsening symptoms should seek medical attention immediately.

DOH and CDC are working closely with healthcare providers and community partners and will continue to provide updates as more information becomes available. At this time, the overall risk to the public is low; however, awareness and early treatment are important to prevent severe iGAS illness.

Source: 

Link: https://health.hawaii.gov/news/newsroom/doh-and-cdc-investigate-invasive-group-a-streptococcal-igas-infections-in-west-hawai%ca%bbi/

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