#USA, #Wastewater Data for Avian #Influenza #H5 (#CDC, March 27 '26)

 

{Excerpt}

(...)

Time Period: March 15, 2026 - March 21, 2026

-- H5 Detection: 9 site(s) (2.0%)

-- No Detection: 436 site(s) (98.0%)

-- No samples in last week: 130 site(s)

(...)

Source: 

Link: https://www.cdc.gov/nwss/rv/wwd-h5.html

_____

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

 

Two wild Canada Geese in the Lounais-Suomen aluehallintovirasto Region.

Source: 

Link: https://wahis.woah.org/#/in-review/7401

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Deciphering #HPAI #Influenza A Virus #H5N1: Molecular Basis of #Pathogenicity, Zoonotic Potential, and Advances in #Vaccination Strategies

 

Abstract

The ongoing panzootic of the highly pathogenic avian influenza (HPAI) H5N1 virus, dominated by clade 2.3.4.4b, constitutes a significant global threat to wildlife, animal health, and public health. Once characterized by sporadic outbreaks, H5N1 has evolved into a sustained, year-round infection with an expanded host range that now includes numerous mammalian species. Its high pathogenicity is primarily driven by the acquisition of a polybasic haemagglutinin cleavage site, enabling systemic viral spread, alongside emerging endothelial and neurotropic properties that contribute to severe disease and high mortality in mammals. Although zoonotic transmission remains limited, H5N1 continues to accumulate mutations associated with mammalian adaptation, particularly within the haemagglutinin and polymerase complex. Notably, recent outbreaks in U.S. dairy cattle highlight the emergence of novel mammalian reservoirs with increased human exposure risk. Concurrently, vaccination strategies are advancing beyond traditional adjuvanted inactivated vaccines toward next-generation platforms, including mRNA and virus-like particle vaccines, designed for rapid deployment and broader immune protection. However, ongoing viral evolution, constrained vaccine availability, and gaps in coordinated surveillance underscore the urgent need for an integrated One Health approach to reduce panzootic risk.

Source: 

Link: https://www.mdpi.com/1999-4915/18/4/410

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On the brink of emergence: an evolutionary approach to #Influenza A virus #H5N1 isolated from #humans

 

Highlights

• A detailed phylogenetic analysis of H5N1 HPAIV isolated from humans was performed.

• All strains infecting humans have acquired substitutions in several key proteins.

• All strains have gained specific substitutions to better adapt to the human host.

• Substitutions in key proteins involved in replication and immune evasion were found.

• A significant degree of polymorphic sites was found in the polymerase complex.

• Substitutions in hemagglutinins and neuraminidases from different clades were found.

Abstract

Avian Influenza Viruses (AIVs) pose today a very significant risk to global health given the widespread circulation of H5N1 highly pathogenic avian influenza viruses (HPAIV). After decimating the avian population all over the world, these viruses spill over to many different mammal species, causing also fatal outbreaks. As the virus continues to evolve increasing human cases of H5N1 HPAIV have been reported, causing concern that these viruses may adapt to the human host and became a pandemic new virus. In order to gain insight into this matter, a detailed phylogenetic analysis of H5N1 HPAIV isolated from humans was performed. A significant number of substitutions have been found in the hemagglutinins (HA) and neuraminidases (NA) among the three H5N1 clades already detected in human cases. Some of these substitutions were found to produce changes in the 3D structure of these proteins. Substitutions providing an evolutionary advantage to replicate or evade the immune response in mammals have been found in several non-structural proteins of strains infecting humans, including regulatory proteins, like PA-X or PB1-F2. A significant degree of polymorphic sites was observed in the proteins of the polymerase complex. The results of these studies are discussed in terms of the evolution of H5N1 HPAIV infecting humans and future work to be done to address the pandemic potential of these viruses.

Source: 

Link: https://www.sciencedirect.com/science/article/pii/S0168170226000353?via%3Dihub

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

 

There is an observation of death of several numbers (30) of crows in the jungle of Tribhuvan University premises.

Source: 

Link: https://wahis.woah.org/#/in-review/7387

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

Frequent sightings of wild birds were reported in the vicinity of the farm. The farm comprises multiple poultry sheds having birds of different age (4-56 weeks) groups. On 15 March, a sudden mortality event occurred in one shed, where approximately 100 commercial layer birds died acutely. Since that incident, mortality has been observed across all sheds on the farm.

Commercial Layers of various age (4-56 weeks) group affected since 15 March, 2026 and a large number of chicken appear slightly droopy or depressed, and die suddenly.

Source: 

Link: https://wahis.woah.org/#/in-review/7386

____

Prophylactic and therapeutic efficacy of #monoclonal #antibodies against #H5N1 #influenza virus

 

Highlights

• mAbs could enhance our armamentarium against H5N1 in support of pandemic preparedness

• Several mAbs have shown prophylactic and therapeutic efficacy against H5N1 in animal models

• Anti-IAV mAbs that have advanced in clinical trials could be evaluated against H5N1

• Resistance emergence during mAb treatment was infrequent in pre- and clinical studies

Abstract

Highly pathogenic avian influenza H5N1 continues to pose a serious zoonotic and pandemic threat due to its increasing cross-species transmission and high virulence in humans. Despite the availability of vaccines and antivirals for seasonal influenza, effective prophylactic and treatment options for H5N1 remain limited. Herein we explore the potential action of monoclonal antibodies (mAbs) against H5N1, focusing on those with demonstrated efficacy in animal models. Most of these mAbs target conserved hemagglutinin epitopes and function as broad neutralizing fusion/entry inhibitors; notably, CR9114 targets both groups 1 and 2 influenza A strains as well as B lineages. Other mAbs prevent viral release by targeting neuraminidase, and those directed against the M2 ectodomain and nucleoprotein function through Fc receptor-mediated pathways. These mAbs have shown robust protection against lethal H5N1 challenge in mice, ferrets, and/or non-human primates. Compounds such as CR6261, MEDI8852, and TCN-032 have been evaluated in clinical trials for seasonal influenza, yielding encouraging safety and pharmacokinetics results and notably, no reported emergence of resistance. Despite these positive results their clinical development was prematurely discontinued. Integrating these highly effective mAbs into our H5N1 pandemic preparedness arsenal is a logical next step to provide a robust prophylactic and therapeutic option at the early stages of an outbreak. Future efforts must address regulatory and logistical barriers, invest in stockpiling and emergency use protocols, and support adaptive clinical trial frameworks to ensure rapid deployment when needed.

Source: 

Link: https://www.sciencedirect.com/science/article/pii/S0924857926000737?via%3Dihub

____

#Dispersal, #adaptation and #persistence of #H5N1 in the sub-Antarctic and #Antarctica

 

Abstract

High pathogenicity avian influenza virus (HPAIV) H5N1 reached the sub-Antarctic and Antarctica in 2023, subsequently spreading to remote locations within this region where it had devastating impacts on seal, penguin and albatross populations. The threat to marine wildlife over this broad area exemplifies the need to understand H5N1 long-distance dispersal and evolution. We obtained 104 novel viral genomic sequences from samples that we collected at South Georgia, Kerguelen, Crozet, Prince Edward, Falklands/Malvinas Islands and the Antarctic Peninsula in a region spanning 8,000 kilometers. Using recent phylogeographic modeling advances we show that H5N1 spread encompassed numerous transmission events between distant locations, accumulating mammalian-adaptive mutations in the process. Seals are the most affected species, but we reveal that the long-distance eastward virus dispersal better aligns with the long-distance movements of large petrels and albatrosses. The risk of H5N1 endemisation, dispersal to other locations and ongoing evolution are highly concerning.

Competing Interest Statement

The authors have declared no competing interest.

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.03.20.713283v1

____

14th Meeting of #WHO #Expert Working Group of the Global #Influenza #Surveillance and Response System (GISRS) for Surveillance of #Antiviral Susceptibility (March 20 '26)

Weekly epidemiological record 

20 MARCH 2026, 101th YEAR, No 12, 2026, 101, 53–56

http://www.who.int/wer 

Executive Summary 

The WHO Expert Working Group on Surveillance of Influenza Antiviral Susceptibility (AVWG) supports the WHO GISRS by providing practical guidance for monitoring antiviral susceptibility of seasonal and emerging influenza viruses through global surveillance efforts. 

The 14th WHO-AVWG meeting was held in virtual format on 10-12 June 2025. 

Update on susceptibility of seasonal influenza viruses to approved antiviral agents 

From approximately May 2024 to May 2025, five WHO Collaborating Centres (CCs) and two National Influenza Centres (NICs) reported co-circulation of influenza A(H1N1) pdm09, A(H3N2), and B/Victoria viruses. 

A(H1N1)pdm09 dominated in Eastern Asia{1}. Elevated frequency of influenza neuraminidase (NA) inhibitor (NAI) reduced inhibition/ highly reduced inhibition (RI/HRI) was identified among A(H1N1)pdm09 viruses, largely conferred by the NA-H275Y substitution. 

Reporting frequency was 3.8% in China, lower (≤1%) in other reporting regions, but still measurable and were in some cases a result of prior antiviral use or specific local outbreaks (e.g., a hospital in Iceland with a NA-H275Y+S247N cluster, a primary school classroom outbreak in Japan{2}. The NA-S247N substitution (≤3.3%) was also noted by three centres, but these viruses exhibited normal inhibition (NI) by NAIs when available isolates were tested. 

Incidence of RI/HRI or NA-associated markers were less frequently reported for A(H3N2) and B/Victoria viruses than A(H1N1)pdm09 viruses. 

Markers and incidence of reduced susceptibility to baloxavir was detected at low frequencies of 0.07 to 2.2%, where the latter value represented a small sample set of only 2 of 89 viruses in Japan. 

Reduced susceptibility or amino acid markers indicative of reduced susceptibility were observed only in influenza A viruses and not influenza B. 

Update on susceptibility of zoonotic and animal influenza viruses  to approved antiviral agents 

From approximately May 2024 to May 2025, global surveillance data from WHO CCs, NICs, and associated partners including WHO Essential Regulatory Laboratories and the OFFLU (WOAH/FAO Network of Expertise on Animal Influenza) network reported that most zoonotic and avian influenza viruses, particularly circulating A(H5N1/x) HA clade 2.3.4.4b and 2.3.2.1a/e viruses, were broadly susceptible to NAIs and baloxavir. 

A(H5N1) 2.3.4.4b virus oseltamivir inhibitory concentrations remain elevated vs. seasonal N1 viruses. 

Small and isolated incidence of NAI associated RI/HRI or markers included: NA-D199G mediated oseltamivir/zanamivir RI detected in A(H5N1) 2.3.4.4b poultry in the Russian Federation (February 2024, reported June 2025), NA-N295S in poultry in India A(H5N1) 2.3.2.1a isolates, and 8 poultry farms in British Columbia, Canada exhibiting A(H5N1) 2.3.4.4b with NA-H275Y. 

Only two viruses with reduced baloxavir susceptibility were identified, 1 human virus with PA-I38M (California, USA) and 1 environmental virus isolate with PA-V100I (China, Hong Kong Special Administrative Region). 

Beyond A(H5N1/x), nearly 30 avian influenza subtypes including A(H9N2), A(H7N2), A(H7N7), and A(H7N9), and A(H10N7) were analysed across surveillance sites in the Bangladesh, Egypt, the Netherlands and the United States of America (USA). 

They generally lacked NA or PA genotypic markers of reduced drug susceptibility and when available for phenotypic testing, were susceptible to both NAIs and baloxavir. 

A(H7N2) and A(H7N7) viruses from the Netherlands displayed oseltamivir RI compared to human seasonal references, but this may be due to foldchange comparison to a mismatched NA subtype. 

Swine-origin variant viruses (A(H1N1)v, A(H1N2)v, A(H3N2)v) tested across the USA and Europe were largely free of genotypic or phenotypic indicators of reduced susceptibility/inhibition to NAIs or baloxavir. 

Some viruses (the  Netherlands) showed slightly higher NAI median inhibitory concentrations to historical or human seasonal baselines, but all remained below NAI RI thresholds. 

Update of protocols and guidance for GISRS laboratories 

Both genotypic and phenotypic assays may be used as tools to monitor susceptibility of influenza viruses to NAIs and baloxavir. 

The WHO-AVWG routinely reviews and updates influenza NA and PA amino acid substitutions associated with reduced susceptibility to NAIs and baloxavir; updated tables for the previous reporting period were included on the WHO website{3–5}. 

The US CDC continues to update and ship reference virus panels that can be used for NAI and baloxavir susceptibility testing, available via the International Reagent Resource{6} 

Further guidance on baloxavir and other PA inhibitor testing included the Influenza Replication Inhibition Neuraminidase-based Assay (IRINA), published by the Centers for Disease Control and Prevention, USA{7} and included on the WHO website{8}. 

The WHO AVWG continues to develop algorithms for NICs to aid in influenza response planning (zoonotic, pandemic, and antiviral resistance-specific events), guidance to aid in decisions making for testing strategies (genotypic vs. phenotypic), and guidance for consideration of baloxavir and PA inhibitor specific amino acid substitutions associated with reduced drug susceptibility{9}. 

Additionally, the WHO-AVWG has worked with GISAID to continue to refine and implement modifications to existing tools to facilitate identification of NA and PA substitutions upon sequence submission. 

Outbreak and pandemic preparedness with clinicians’ perspectives 

Two physicians, Profs. Prof. David Hui and Bin Cao, were invited to present recently updated WHO guidance on clinical practice guidelines for influenza{10}. 

Significant updates and discussion surrounded inclusion of baloxavir, which was conditionally recommended for non-severe disease high-risk patients and post-virus exposure prophylaxis (PEP) including influenza viruses associated with high mortality. 

Conditional recommendation against any NAI or baloxavir intervention remains for non-severe disease low-risk patients or seasonal virus PEP. 

Data was presented on multiple PA inhibitors rapidly moving through late-stage clinical trials in China which may have implications on expanded usage of this newer class of influenza drugs. 

Review of External Quality Assessment Programme (EQAP) panels 

EQAP was initiated in 2007 to monitor the quality of GISRS, NICs, other national influenza reference laboratories’ capacity for influenza diagnosis and detection. 

An optional antiviral phenotypic NAI panel was introduced in 2013, and genotypic baloxavir susceptibility was introduced in 2020. 

Results for the 2024 Global EQAP panel were reported during the 14th WHO-AVWG meeting. 

Of the 194 participating laboratories, 26.3% participated in NAI susceptibility testing. 

Results and subsequent discussion from this year’s panel were used by members of WHO-AVWG to assess the training needs of NICs. 

Way forward 

The 2020–2023 Annual Global Update on the Susceptibility of Influenza Viruses (Global AVS) manuscript was published{11} and drafting of a 2023–2025 publication is underway. The next WHO-AVWG meeting will be held in June 2026.

___

{1} World Health Organization. Influenza Transmission Zones. 2026. https://cdn.who.int/media/docs/ default-source/influenza/influenzaupdates/2025_09_24_influenza-transmission-zones. pdf?sfvrsn=22361408_3&download=true. 

{2} Takashita E, Shimizu K, Usuku S, Senda R, Okubo I, Morita H, et al. An outbreak of influenza A(H1N1) pdm09 antigenic variants exhibiting cross-resistance to oseltamivir and peramivir in an elementary school in Japan, September 2024. Euro Surveill. 2024;29(50).

{3} World Health Organization. Summary of neuraminidase (NA) amino acid substitutions assessed for their effects on inhibition by neuraminidase inhibitors (NAIs). 2025. https://cdn.who.int/media/docs/default-source/ influenza/laboratory---network/quality-assurance/human-nai-marker-table_ for-publication_final_20240918.pdf. 

{4} World Health Organization. Summary of neuraminidase (NA) amino acid substitutions assessed for their effects on inhibition by NA inhibitors (NAIs) among avian influenza viruses of Group 1 (N1, N4, N5, N8 subtypes) and Group 2 (N2, N3, N6, N7, N9 subtypes) NAs. 2025. https://cdn.who.int/media/ docs/default-source/influenza/avwg/avian-nai-marker-whotable__10-10-2025.pdf?sfvrsn=bc0d1e9a_10 

{5} World Health Organization. Summary of polymerase acidic protein (PA) amino acid substitutions assessed for their effects on PA inhibitor (PAI) baloxavir susceptibility. 2025. https://cdn.who.int/media/docs/default-source/influenza/ laboratory---network/quality-assurance/antiviral-susceptibility-influenza/ pa-marker-who-table_28-11-2025_updated.pdf?sfvrsn=5307d6fe_4. 

{6} International Reagent Resource. 2026. https://www. internationalreagentresource.org/. 

{7} Patel MC, Flanigan D, Feng C, Chesnokov A, Nguyen HT, Elal AA, et al. An optimized cell-based assay to assess influenza virus replication by measuring neuraminidase activity and its applications for virological surveillance. Antiviral Res. 2022;208:105457. 

{8} World Health Organization. Baloxavir Susceptibility Assessment using Influenza Replication Inhibition Neuraminidase-based Assay (IRINA). https:// cdn.who.int/media/docs/default-source/influenza/avwg/cdc-phenotypic-lp492rev01d---baloxavir-susceptibility-assessment-using-irina.pdf? 

{9} Patel MC, Nguyen HT, Mishin VP, Pascua PNQ, Champion C, Lopez-Esteva M, et al. Antiviral susceptibility monitoring: testing algorithm, methods, and f indings for influenza season, 2023-2024. Antiviral Res. 2025;244:106299. 

{10} World Health Organization. Clinical practice guidelines for influenza 2024. https://www.who.int/publications/i/item/9789240097759.

{11} Hussain S, Meijer A, Govorkova EA, Dapat C, Gubareva LV, Barr I, et al. Global update on the susceptibilities of influenza viruses to neuraminidase inhibitors and the cap-dependent endonuclease inhibitor baloxavir, 2020-2023. Antiviral Res. 2025:106217.

___

Source: 

Link: https://iris.who.int/server/api/core/bitstreams/1ea408da-cd90-438b-b80c-b00aaf4e7315/content

____

#USA, #Wastewater Data for Avian #Influenza #H5 (#CDC, March 20 '26)

 

{Excerpt}

Time Period: March 08, 2026 - March 14, 2026

-- H5 Detection: 8 site(s) (1.8%)

-- No Detection: 444 site(s) (98.2%)

-- No samples in last week: 120 site(s)

(...)

Source: 

Link: https://www.cdc.gov/nwss/rv/wwd-h5.html

____

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

 

By USFWS Mountain-Prairie - Canada goose on Seedskadee NWR, Public Domain, https://commons.wikimedia.org/w/index.php?curid=69188087

___

A wild Canada Goose in Etelä-Suomen aluehallintovirasto Region.

Source: 

Link: https://wahis.woah.org/#/in-review/7384

____

Dynamics and #control of highly pathogenic #H5 avian #influenza in a threatened #pelican population

 

Abstract

The ongoing epizootic of highly pathogenic avian influenza (HPAI) continues to cause massive deaths in wildlife. Fundamental understanding of its disease ecology in natural populations is urgently needed. This knowledge has been hindered by the difficulty of acquiring data on epidemic dynamics. Here, using data collected from a threatened population of Dalmatian pelicans (Pelecanus crispus), we recover the epidemiological and evolutionary history of one of the largest HPAI wildlife mortality events. The results show that this devastating outbreak was likely seeded by a single introduction associated with movement of the species. By estimating epidemiological features of two consecutive outbreaks in the same population, we show that panzootic H5N1 since 2022 likely exhibits higher transmissibility and longer shedding time in non-reservoir birds, compared to previous H5NX subtypes. We also evaluate effectiveness of past and future control measures: carcass removal during the outbreak is shown to have surprisingly little impact on mitigating the mortality; and current H5 vaccines relying on capture and injection to deliver cannot establish herd immunity in a wildlife population. The results provide the first field evidence supporting the hypothesis that viral fitness difference of H5N1 to previous H5NX subtypes is the key cause of the expanded epizootic and panzootic since 2022, and on highly debated HPAI management strategies in wildlife populations.

Competing Interest Statement

The authors have declared no competing interest.

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.03.16.712014v1

____

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

{Bântéay Méanchey, Preah Netr Preah} On 12 March 2026, the outbreak investigation team visited a backyard chicken farm following reports of illness and mortality suspected to be caused by Avian Influenza (AI). During the visit, deaths of wild birds were also observed in the area. A total of six chicken samples were collected and submitted to NAHPRI/GDAHP for testing of Avian Influenza (H5N1). Laboratory results confirmed on 16 March 2026 that 4 out of 6 chicken samples tested positive for Avian Influenza (H5N1). In addition, 13 wild bird carcasses were collected and submitted for laboratory testing. On 16 March 2026, all wild bird samples were confirmed positive for Avian Influenza (H5N1).

{Bântéay Méanchey, Serei Saophoan} On 25 January 2026, the outbreak investigation team visited a backyard chicken farm following reports of illness and mortality suspected to be caused by Avian Influenza (AI). Two chicken samples were collected and submitted to NAHPRI/GDAHP for testing of AI (H5N1). On 26 January 2026, laboratory results confirmed that both samples tested positive for Avian Influenza (H5N1).

Source: 

Link: https://wahis.woah.org/#/in-review/7376

____

#Cambodia: one new #human #infection with avian #influenza virus #H5N1 (HK CHP, March 17 '26)

{Excerpts}

Avian Influenza Report - VOLUME 22, NUMBER 11 - Reporting period: March 8, 2026 – March 14, 2026 (Week 11) (Published on March 17, 2026) 

(...)

-- Date of report: 14/03/2026

-- Country: Cambodia

-- Province / Region District / City: Banteay Meanchey province, Preah Netr, Preah district

-- Sex: Female

-- Age: 45

-- Condition at time of reporting: Hospitalised

-- Subtype of virus: H5N1 

(...)

Source: 

Link: https://www.chp.gov.hk/files/pdf/2026_avian_influenza_report_vol22_wk11.pdf

____

#Cambodia reported one additional #human case of #infection with #H5N1 avian #influenza virus (MoH, March 16 2026)

 

{Automatic translation, edited}

Kingdom of Cambodia - Press Release

A Case of Bird Flu in a 45-year-old Woman

The Ministry of Health of the Kingdom of Cambodia would like to inform the public that there is 1 case of bird flu in a 45-year-old woman who was confirmed to be positive for the H5N1 avian influenza virus on March 14, 2026 by the National Institute of Public Health.

The patient resides in Ropai village, Chinu Meanchey commune, Preah Net Preah district, Banteay Meanchey province, and there were reports of sick and dead chickens in the village. 

On the same day, the patient was placed in isolation at the hospital and was treated with Tamiflu and received careful care from the medical team. 

Upon inquiry, it was revealed that the patient raised chickens and ducks, including some sick and dead chickens. 3 days before testing positive, she had come into contact with the dead chicken.

The National and Sub-National Health Ministry's Emergency Response Team has been collaborating with the Provincial Department of Agriculture and local authorities at all levels to actively investigate the outbreak of bird flu and respond according to technical methods and protocols, find sources of infection in both animals and humans, and search for suspected cases and contacts to prevent further transmission in the community. 

In addition, Tamiflu is being distributed to close contacts and conduct health education campaigns in the villages where the outbreak occurred. 

The Ministry of Health would like to remind all citizens to always be vigilant about bird flu because H5N1 bird flu continues to threaten the health of our citizens. 

We would also like to inform you that if you have a fever, cough, sputum, or difficulty breathing and have been in contact with sick or dead chickens in the 14 days before the onset of symptoms, do not go to crowded places or towns and seek consultation and treatment at the nearest health center or hospital immediately to avoid delaying and putting you at high risk of eventual death. 

-- How it is transmitted: 

- H5N1 bird flu is a type of flu that is usually spread from sick birds to other birds, but it can sometimes be spread from birds to humans through close contact with sick or dead birds.

- Bird flu in humans is a serious illness that requires prompt hospital treatment.

- Although it is not easily transmitted from person to person, if it mutates, it can be contagious, just like seasonal flu.

- Do not touch or eat sick or dead chickens and wear gloves and a mask or a scarf to cover your nose before handling chickens and ducks for cooking. Then blanch them in boiling water before plucking.

- Follow good hygiene practices, wash your hands frequently before handling food, especially after touching poultry or other objects that may be sources of contamination.

- Cook food thoroughly before eating, especially meat, poultry and eggs. Do not eat raw or undercooked eggs and keep raw and cooked food separate. Clean cooking utensils properly.

- If there are many sick or dead chickens at home or in the village and there are symptoms of fever, cough, sputum discharge or difficulty breathing, please immediately seek consultation and medical examination at the nearest health center or hospital to avoid delay, which puts you at high risk of sudden death. 

- Therefore, the public is requested to be aware and take care of their health in the above preventive measures. 

The Ministry of Health will continue to provide information regarding public health issues on the official social media of the Ministry of Health www.moh.gov.kh as well as the official Facebook page of the Department of Communicable Disease Control and the website www.cdcmoh.gov.kh. For more information, please contact the Ministry of Health's hotline number 115 toll-free.

Source: Ministry of Health of Cambodia, https://moh.gov.kh/en/home

Link: https://moh.gov.kh/en/notice/detail/453

____

Increased contact #transmission of contemporary #Human #H5N1 compared to #Bovine and Mountain #Lion H5N1 in a hamster #model

 

Abstract

The ongoing outbreak of highly pathogenic avian influenza virus (HPAIV) subtype H5N1 in the U.S. poses a significant public health threat. To date, 70 human cases have been confirmed in the United States, including two severe cases and one fatality. While suitable animal models are crucial for predicting the potential pandemic risk of newly emerging pathogens in humans, studies investigating contemporary HPAIV H5N1 transmission dynamics remain limited. Here, we investigate the pathogenicity and transmission efficiency of recent clade 2.3.4.4b H5N1 viruses isolated from a bovine, mountain lion, and a human case using Syrian hamsters. Intranasal inoculation results in productive virus replication in the respiratory tract and shedding for all three isolates. Transmission studies demonstrate limited efficiency via direct contact and airborne routes for all isolates. Although overall transmission is inefficient, the human H5N1 isolate demonstrates relatively greater contact transmissibility than the bovine and mountain lion isolates. Taken together, our findings demonstrate that the Syrian hamster model complements existing animal models for influenza A virus research and expands the resources available for investigating the pathogenicity, transmissibility, and efficacy of countermeasures against HPAIV H5N1.

Source: 

Link: https://www.nature.com/articles/s41467-026-68900-8

____

#USA, #Wastewater Data for Avian #Influenza #H5 (#CDC, March 13 '26)

{Excerpt}

Time Period: March 01, 2026 - March 07, 2026

-- H5 Detection: 8 site(s) (1.6%)

-- No Detection: 491 site(s) (98.4%)

-- No samples in last week: 77 site(s)

(...)

Source: US Centers for Disease Control and Prevention, 

Link: https://www.cdc.gov/nwss/rv/wwd-h5.html

____

#Peru - #Influenza A #H5 viruses of high pathogenicity (Inf. with) (non-poultry including wild birds) (2017-) - Immediate notification

 

In the framework of passive surveillance activities, a report was received regarding backyard poultry (not considered as poultry) with clinical symptoms consistent with avian influenza. An outbreak of high pathogenicity avian influenza has been confirmed in the Cajabamba district of the Cajamarca department. The birds showed clinical signs such as weakening, hoarseness, eye discharge, and diarrhoea. The Official Authority activated quarantine, control, and surveillance measures in the outbreak and around the outbreak with the aim of identifying possible cases and preventing the spread of the outbreak.

A notification was received regarding sick birds in a backyard (turkeys, ducks, roosters, hens, geese, and chickens) showing signs of depression, diarrhoea, and hoarseness.

Source: WOAH, https://wahis.woah.org/#/home

Link: https://wahis.woah.org/#/in-review/7358

____

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

 

{Northern Ireland}

Pheasant breeder flock, with a small mixed backyard flock with chicken, geese. Positive test for HPAI H5N1, clinical signs presented prior to testing.

Source: 

Link: https://wahis.woah.org/#/in-review/7368

____

A newly emergent N1 #neuraminidase associated with clade 2.3.4.4b highly pathogenic avian #influenza #H5 viruses in North #America

 

Abstract

We investigated the evolutionary history of the newly emergent neuraminidase (am4N1) associated with the D1.1 and D1.2 genotypes of highly pathogenic avian influenza A(H5N1) viruses in North America. Phylogenetic inference places am4N1 in a sister clade to Eurasian avian, swine, and human A(H1N1)pdm09 viruses and distinct from 1918, pre-2009 human seasonal, and classical swine A(H1N1) lineages. Am4N1 descends from diverse avian N1 genes endemic to the Americas. Phylodynamic analysis indicates a monophyletic am4N1 lineage with numerous introductions of viruses carrying the am4N1 gene likely originating from western Canada into the United States during emergence of the D1.1 and D1.2 genotypes. The lineage has diversified and accumulated deletions in the stalk domain. Despite amino acid divergence, structural modeling shows conserved neuraminidase architecture in the globular head. Given its distinct ancestry and amino acid sequence, further studies are needed to assess cross-reactivity of antibodies from prior human A(H1N1)pdm09 infections.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

This study did not receive any external funding.

Source: 

Link: https://www.medrxiv.org/content/10.64898/2026.03.09.26347929v1

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