#Cambodia reported fourth #human #infection with #H5N1 #influenza virus this year (ANTARA, Apr. 23 '26)

 

{Excerpt}

PHNOM PENH (ANTARA) - A 66-year-old woman from Svay Rieng province, southeastern Cambodia, has been confirmed positive for H5N1 bird flu, becoming the fourth case in 2026, the Ministry of Health said in a statement on Wednesday.

The victim, who lives in Trapaing Thkov village in Romduol district, was confirmed positive for the virus by the Cambodian National Institute of Public Health on Tuesday (April 21).

The patient is currently being quarantined at a hospital under intensive care by a team of doctors, the statement said.

(...)

Source: 

Link: https://m.antaranews.com/amp/berita/5537212/kamboja-konfirmasi-kasus-keempat-flu-burung-pada-manusia

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Heart-nosed #bat #alphacoronaviruses use #human CEACAM6 to enter #cells

 

Abstract

Identifying viruses with zoonotic potential on the basis of their ability to enter human cells is a critical component of pandemic prediction, prevention and preparedness. Here using a computational approach that retains maximum phylogenetic diversity, we selected an optimal subset of alphacoronavirus spike proteins to screen against broad coronavirus receptor libraries. Most of the selected spike proteins did not use any of the established coronavirus receptors. However, the pseudotyped spike protein of Cardioderma cor (heart-nosed bat) coronavirus KY43 (CcCoV-KY43) could enter human cells. Using a recombinant CcCoV receptor-binding domain (RBD) and a human receptor screening platform, we identified direct interactions with the human CEACAM proteins CEACAM3, CEACAM5 and CEACAM6. Overexpression of human CEACAM6—a protein widely expressed in the human lung—conferred permissivity to otherwise refractory human cells. A crystal structure showed that the RBD binds the amino-terminal IgV-like domain of human CEACAM6. Immune surveillance studies using sera of individuals from the Taveta region of Kenya, where CcCoV-KY43 was identified, did not show significant evidence of recent spillover. Wider characterization of alphacoronaviruses related to CcCoV-KY43 showed that human CEACAM6 is used by two other CcCoVs collected in Kenya. Moreover, there was more restricted nonhuman CEACAM6 tropism for viruses isolated from Rhinolophus bats from Russia and China. Thus, alphacoronaviruses that use CEACAM6 are probably geographically widespread, and viruses from East Africa show potential for transmission to humans.

Source: 

Link: https://www.nature.com/articles/s41586-026-10394-x

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Next-Generation #Sequencing #Strategies During the 2024–2025 Avian #Influenza #H5N1 #Emergency Response in the #US

 

Abstract

The first influenza A(H5N1) human case associated with the A(H5N1) dairy cattle outbreak in the United States was identified in April 2024. The U.S. CDC response to this outbreak was activated days later and remained active until July 2025. During this time, 70 human cases of influenza A(H5N1) were detected with a range of epidemiological links to sources of exposure. Next-generation sequencing (NGS) of human samples was an effectual mechanism for tracking and analyzing the outbreak evolution throughout the response. Due to the specimens’ importance and their variable physical quality, an assortment of laboratory methods was utilized including influenza segment-specific amplification, enrichment capture, short-read, and long-read sequencing. Combining these methods allowed for high-quality genomic data production with rapid turnaround times—typically 2 days from sample receipt to public database submission. By leveraging replicate sequencing, enrichment capture, and sequencing of diagnostic amplicons, valuable genomic data could be produced directly from human clinical specimens that would have normally been considered too weak for routine virologic surveillance sequencing. The resulting assemblies were characterized and analyzed by CDC and shared with local and state public health authorities to facilitate case investigations and risk assessment. These data were further used for phylogenetic analyses of viruses from human cases to investigate likely animal-to-human transmission events and identify clusters within the outbreak that might indicate trends in the types of exposures. Through the adaptable laboratory workflow and the rapid release of viral genomic data, the public health risk mitigation strategies could be evaluated and adjusted in real time.

Source: 

Link: https://www.mdpi.com/1999-4915/18/4/482

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Avian #Influenza #Report - Reporting period: April 12 - 18 '26 (Wk 16) (HK CHP, April 21 '26): 3 new #human cases of #H9N2 virus in #China

 

{Excerpt}

(...)

Avian influenza A(H9N2): 

-- Guangdong Province: 

1) A five-year-old boy with onset on February 23, 2026.

-- Jiangxi Province: 

2) A two-year-old boy with onset on March 20, 2026. 

-- Yunnan Province:

3) A two-year-old girl with onset on March 3, 2026. 

(...)

Source: 

Link: https://www.chp.gov.hk/files/pdf/2026_avian_influenza_report_vol22_wk16.pdf

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Emergence of D1.1 #reassortant #H5N1 avian #influenza viruses in North #America

 

Abstract

Since 2021, highly pathogenic avian influenza viruses (HPAIVs) belonging to H5N1 clade 2.3.4.4b have circulated widely in North American wild birds and repeatedly spilled over into mammals. In 2025, the first H5N1-associated deaths in humans were recorded in the Western hemisphere, raising questions about how the ongoing evolution of the virus in wild birds impacts spillover risk. Here, our analysis of 21,471 H5N1 genomes identified an evolutionary shift in mid-2024, driven by interhemispheric migration from Asia and reassortment with new antigens. The genotypes that dominated the early years of North America's H5N1 epizootic traced their ancestry back to Europe, but Asia was the source of new "D1.1" genotype viruses that (a) spread faster, (b) have higher reassortment potential, (c) a broader host range, (d) repeatedly spill over to bovines, and (e) cause severe disease in humans, including non-farm workers.

Competing Interest Statement

The authors have declared no competing interest.

Funder Information Declared

Research Foundation - Flanders, https://ror.org/03qtxy027, G098321N, G0E1420N

European Union Horizon 2023 RIA project LEAPS, 101094685

DURABLE EU4Health project 02/2023-01/2027, 101102733

Fonds National de la Recherche Scientifique, F.4515.22

European Union Horizon 2020 project MOOD, 874850

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, 75N93021C00014

Source: 

Link: https://www.biorxiv.org/content/10.64898/2025.12.19.695329v2

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#Taiwan #CDC issued a #statement regarding journal research on transmission of viruses from farmed #shrimp in #China to #humans (Apr. 18 '26)

 

Recently, online discussions have focused on a study published in the international journal *Nature Microbiology*, which suggests that *Cryptant Dead Noda Virus* (CMNV), found in aquatic animals, may have the potential to spread across species to humans, potentially causing persistent high-tension viral anterior uveitis (POH-VAU). 

The Centers for Disease Control (CDC) stated that currently only China has reported suspected human cases of CMNV, distributed across 18 provinces with high aquaculture activity. 

Major international public health organizations such as the WHO, the US CDC, and the European Centre for Disease Prevention and Control (ECDC) have not reported any CMNV-related cases or listed it as an urgent threat. 

The CDC assesses the risk of domestic transmission as extremely low and will continue monitoring with agricultural authorities.

The CDC further explained that the study infers that human infection with CMNV may be related to handling or consuming raw seafood; however, further evidence is needed to confirm whether this virus has the ability to effectively infect human eye tissue. 

The Taiwan Centers for Disease Control (CDC) emphasizes that there have been no large-scale human outbreaks or community transmission events caused by CMNV globally at present, and there is no evidence of infection through the general consumption of cooked seafood. 

The CDC will continue to monitor relevant international outbreaks, develop human specimen testing technologies and methods, and establish relevant sampling and testing conditions for risk monitoring and early warning.

According to the monitoring of the Animal and Plant Health Inspection and Quarantine Bureau of the Ministry of Agriculture, there have never been any CMNV outbreaks in shrimp farms in Taiwan. 

The CDC's overall assessment is that the risk of domestic transmission is extremely low, but both agriculture and health authorities will continue to strengthen monitoring. 

CMNV has been listed as an emerging infectious disease by the World Organisation for Animal Health, and infection cases have been reported in shrimp farms in China and Thailand. 

The CDC urges travelers to China and Thailand to take special precautions against CMNV, including thoroughly cooking seafood, avoiding raw seafood for high-risk groups (such as those with chronic diseases), wearing gloves when handling raw seafood, avoiding direct contact with raw food if hands are open, and washing hands thoroughly with soap and water after handling to reduce the risk of infection by various pathogens.

Source: 

Link: https://www.cdc.gov.tw/Bulletin/Detail/JAKoFRedyjAVo_zmdBsCfQ?typeid=9

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Avian #Influenza #Report - Reporting period: April 5 – 11, '26 (Wk 15) (HK CHP April 14, 2026): 2 new #human #H9N2 influenza cases in #China

 

{Excerpt}

(...)

-- Avian influenza A(H9N2): 

- Guangdong Province: 

1) A three-year-old boy with onset on January 20, 2026. 

- Guangxi Zhuang Autonomous Region: 

2) A 63-year-old man with onset on February 5, 2026. 

(...)

Source: 

Link: https://www.chp.gov.hk/files/pdf/2026_avian_influenza_report_vol22_wk15.pdf

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#Population #immunity to clade 2.3.4.4b #H5N1 is dominated by anti - #neuraminidase #antibodies

 

ABSTRACT

Clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) viruses continue to expand geographically and across mammalian hosts, raising concern about pandemic potential. The degree and specificity of pre-existing immunity in humans are key determinants of this risk. We analyzed hemagglutinin (HA)- and neuraminidase (NA)-specific antibody responses in 300 sera collected from adults in New York City. While HA directed binding antibodies to clade 2.3.4.4b H5 were low and hemagglutination-inhibiting antibodies were absent, we detected widespread binding and functional NA antibodies against N1 neuraminidases from clade 2.3.4.4b H5N1 viruses. Neuraminidase inhibition (NI) titers were highest against North American D1.1 genotype N1 viruses and correlated strongly with neutralizing activity, whereas HA-binding antibodies did not. An additional N-linked glycosylation site, as found in the NA of a human D1.1 isolate from British Columbia, reduced susceptibility to NI antibodies. Antibodies titer to N5 from H5N5 were low to minimal. These findings indicate that population-level immunity to clade 2.3.4.4b H5 viruses is dominated by NA-directed antibodies, with important implications for pandemic risk assessment.

IMPORTANCE

Understanding how pre-existing human immunity shapes susceptibility to emerging influenza viruses is central to pandemic preparedness. Here, we determined that human sera contain widespread, functional antibodies targeting H5N1 neuraminidase, which correlate with virus neutralization, whereas HA-directed responses are limited. We further show that acquisition of an NA glycosylation site reduces antibody inhibition, highlighting a potential pathway for immune evasion. These results identify neuraminidase-specific immunity as a major immunological barrier to severe H5N1 disease in humans and emphasize the need to incorporate NA antigenicity into influenza surveillance, risk assessment, and next-generation vaccine design.

Source: 

Link: https://journals.asm.org/doi/10.1128/mbio.00445-26

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ONWARD: a #OneHealth, pan - #European multidisciplinary #network advancing #surveillance, #research, clinical management and control of zoonotic #hepeviruses

 

Highlight

• HEV remains the leading cause of acute viral hepatitis in Europe

• Surveillance and diagnostics for HEV are heterogeneous across EU/EEA

• Zoonotic HEV circulates widely in pigs, wildlife and food chains

• Rat HEV expands the zoonotic spectrum and clinical burden in Europe

• ONWARD integrates One Health surveillance, research and capacity building

Abstract

Zoonotic hepeviruses, particularly hepatitis E virus (HEV, species Paslahepevirus balayani) represent a major yet underestimated public health challenge in Europe. Despite being the leading cause of acute viral hepatitis, surveillance, diagnostic practices and prevention strategies remain heterogeneous across EU/EEA countries, limiting comparability and hindering accurate burden estimates. Underdiagnosis is further compounded by extrahepatic manifestations and the growing impact of chronic HEV infection in immunocompromised patients. At the human–animal–environment interface, zoonotic HEV circulates widely in domestic pigs, wildlife and food products, while coordinated surveillance and control measures remain inconsistently implemented. The recent recognition of ratHEV (species Rocahepevirus ratti) as a cause of acute and chronic hepatitis in Europe further expands the spectrum of zoonotic hepevirus infections and underscores the need for integrated One Health approaches. To address these challenges, the One Health Zoonotic Hepevirus Network (ONWARD; COST Action CA24140) was launched in 2025 as a pan-European, multidisciplinary collaboration uniting experts across human, veterinary, food safety and environmental health sectors. ONWARD aims to harmonise diagnostic tools, strengthen clinical research, integrate multisectoral surveillance, promote capacity building and support evidence-based policy development. By fostering coordination with European stakeholders ONWARD provides a structured framework to strengthen preparedness, surveillance and response to zoonotic hepevirus threats across Europe.

Source: 

Link: https://www.sciencedirect.com/science/article/pii/S1386653226000338?dgcid=rss_sd_all

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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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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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#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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Q1020R in the #spike proteins of #MERS-CoV from Arabian #camels confers resistance against soluble #human #DPP4

 

ABSTRACT

The Middle East respiratory syndrome coronavirus (MERS-CoV) is a pre-pandemic coronavirus that is transmitted from camels, the natural reservoir, to humans and can cause severe disease. MERS cases have been documented in Arabia but not Africa, although the virus is circulating in both Arabian and African camels. Further, evidence has been provided that viruses in African camels might have a reduced capacity to cause disease. However, the underlying determinants are incompletely understood. Here, employing pseudotyped particles as model systems for MERS-CoV entry into cells, we compared cell entry of viruses from African and Arabian camels and its inhibition. We show that viruses found in Arabian camels and recent human cases are less susceptible to inhibition by human soluble DPP4 (sDPP4) than viruses from African camels, although both enter human cells efficiently and are comparably sensitive to inhibition by interferon-induced transmembrane (IFITM) proteins and neutralizing antibodies. Furthermore, relative resistance to sDPP4 was linked to mutation Q1020R, present in the spike proteins of recent Arabian but not African viruses. Finally, indirect evidence was obtained that sDPP4 in human plasma can inhibit MERS-CoV cell entry. These results support the concept that soluble DPP4 might constitute a natural barrier against human infection that is more efficiently overcome by viruses currently circulating in Arabian camels than those in African camels.

Source: 

Link: https://journals.asm.org/doi/10.1128/jvi.00282-26

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#Taiwan, First locally acquired case of #H7N7 avian #influenza A virus has been released from isolation today (MoH, April 3 '26)

 

The Taiwan Centers for Disease Control (CDC) announced today (April 3) that the first case of local human infection with the H7 subtype of novel influenza A, which was detected recently, has been cured and discharged from isolation today after clinical treatment. 

The patient's condition has continued to improve and all tests have been negative. The patient will continue to be monitored until April 6.

The Taiwan Centers for Disease Control (CDC) stated that the sputum sample collected from the case on March 27th was genetically sequenced to identify the virus as H7N7, a low-pathogenic avian influenza virus (LPAI). 

No drug-resistant mutations were found, and the virus remains sensitive to antiviral drugs; the public need not panic. 

The CDC also today, in accordance with the International Health Regulations (IHR), notified the World Health Organization of this first locally acquired H7N7 influenza case through the IHR contact window.

The Taiwan Centers for Disease Control (CDC) explained that since 1959, more than 90 human cases of H7N7 have been reported globally, concentrated before 2003, mainly in Europe. 

Of these, only one case resulted in death, and the vast majority were mild cases of conjunctivitis. 

Subsequently, Italy reported three cases in 2013, also mild cases of conjunctivitis. 

No new human cases have been reported since 2013, but the virus continues to spread and evolve in birds. 

The genetic analysis of the first H7 case in Taiwan showed that it was significantly different from the H7 cases in European human cases 10-20 years ago, and most similar to the H7 cases detected in wild birds in Taiwan over the years. 

No mutations related to enhanced bird-to-human transmission were found, and it is judged to be an isolated event with manageable risks.

The Centers for Disease Control (CDC) reiterates its reminder that workers in the poultry and livestock industries should adhere to disease prevention guidelines, including wearing protective equipment and proper disinfection after handling. 

If respiratory or eye symptoms develop, seek medical attention immediately and inform the animal contact history. 

The public should also follow the "5 Dos and 6 Don'ts" principle to avoid contact with or purchase poultry and livestock products from unknown sources, jointly safeguarding public health and safety. 

More information can be found on the CDC website (https://www.cdc.gov.tw/) or by calling the disease prevention hotline 1922.

Source: 

Link: https://www.cdc.gov.tw/Bulletin/Detail/oWFPJ8DnGZKl-Ygm43iPQQ?typeid=9

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#Taiwan: First locally acquired #human case of novel avian #H7 #influenza virus has been detected (MoH, edited)

 

The Taiwan Centers for Disease Control (CDC) announced today (March 2nd) the first locally transmitted case of novel H7 subtype avian influenza in Taiwan. 

The patient is a man in his 70s from central Taiwan who works in poultry farming and has a history of chronic illness. 

He developed symptoms of runny nose, cough, and body aches on March 20th and sought medical attention at a hospital on March 22nd due to fever. 

He was admitted to the hospital on the same day. 

Imaging examination revealed pneumonia. 

Based on clinical symptoms, test results, and the patient's contact history, the doctor reported the case as a novel H7 avian influenza and administered antiviral medication. 

Further testing and gene sequencing by the CDC confirmed the virus as H7 subtype avian influenza. 

Sequence analysis showed that this H7 belongs to the Eurasian lineage and is similar to the H7 subtype avian influenza viruses monitored in wild birds (mainly ducks and anadidae) in Taiwan over the years. 

However, it is different from the H7N9 subtype avian influenza virus that circulated in mainland China from 2013 to 2019, and is a low-pathogenic avian influenza virus. 

This morning, the CDC convened a meeting with agricultural authorities and relevant medical and veterinary experts to discuss the case and, based on the test results, confirmed it as a case of novel H7 avian influenza in humans. 

The patient's condition has improved and they are continuing isolation and treatment. 

The Centers for Disease Control (CDC) stated that after the first locally transmitted case of H7 subtype novel influenza A was detected in Taiwan, health and agricultural authorities immediately launched a joint epidemic prevention operation to carry out relevant investigations and prevention measures. 

Health authorities, with the assistance of epidemiologists and the Health Bureau, conducted on-site epidemiological investigations at the patient's residence, poultry farm, and hospital. 

Currently, 33 close contacts are under health monitoring and management, and 3 have been given preventative medication based on risk assessment. 

Tests were conducted on 6 family members, all of whom tested negative. 

Agricultural authorities immediately implemented movement restrictions at the poultry farm, and animal testing results were negative for avian influenza virus. 

To clarify the source of infection, today's expert meeting resolved to request the farm to expand testing at nearby poultry farms and to cooperate with wild bird associations to collect droppings from surrounding wild birds. 

Furthermore, the CDC will continue to cooperate with the farm to obtain the gene sequence of the H7 virus detected in Taiwan for further comparison. 

Health and agricultural authorities will continue to strengthen surveillance of humans and animals, including respiratory viruses and influenza/novel coronavirus pneumonia surveillance in medical institutions, active surveillance of poultry farms and migratory birds, and will cooperate with farmers to promote personal protective measures for poultry farmers and public health education. 

They have also contacted duck farming associations to distribute 40,000-50,000 masks free of charge to duck farmers. 

The Centers for Disease Control (CDC) pointed out that, based on current epidemiological investigations and test results, the genetic analysis of this case shows a low-pathogenic avian influenza virus, without any mutations increasing the risk of avian-to-human transmission, and it remains a common avian virus. 

The initial assessment is that this case is an isolated incident. 

Considering the patient's improved condition after treatment, the lack of mutations increasing the risk of avian-to-human transmission in the preliminary genetic analysis, the negative test results at the poultry farm, and the absence of any other family members showing symptoms after the patient's onset, the risk is assessed as controllable, and there is no immediate risk of the outbreak expanding. 

However, to understand the potential risks of this case, they will continue to track the symptoms and test results of contacts, further analyze the virus and trace possible sources of infection, and have activated a joint working group on the risk assessment of zoonotic infectious diseases between agriculture and health authorities to conduct a comprehensive risk assessment. 

The Taiwan Centers for Disease Control (CDC) will notify the World Health Organization (WHO) today through the IHR contact window in accordance with the International Health Regulations (IHR).

According to surveillance data, since the novel influenza A virus was classified as a Category 5 notifiable infectious disease in Taiwan in 2014, a total of 5 sporadic cases have been reported. Besides this case, the others were reported in 2017 (H7N9, imported from outside China), 2021 (H1N2v), 2022 (H1N2v), and 2023 (H1N2v). In addition, there were 4 confirmed cases of H7N9 imported from outside China in 2013-2014; none of the contacts were infected.

The CDC explained that the H7N9 sequence in today's reported case is only closely related to one other human case, H7N4, reported in Jiangsu, China in 2018. The case involves a 68-year-old woman with a history of coronary heart disease and hypertension. She developed symptoms such as cough, weakness, and muscle aches on December 25, 2017, and was hospitalized for pneumonia on January 1, 2018, and discharged on January 22 after recovery. Prior to the onset of illness, the patient had contact with live poultry. Her close contacts did not develop any suspected symptoms during the observation period. The virus remains avian and has not shown resistance to existing antiviral drugs.

The Centers for Disease Control (CDC) reminds workers involved in poultry and livestock farming to implement self-protection measures during operations and to conduct thorough disinfection after work to reduce the risk of infection with the novel influenza A. If symptoms of acute respiratory infection or conjunctivitis appear, seek medical attention immediately and proactively inform healthcare professionals of your occupational history of contact with animals to facilitate early diagnosis. The public is advised to implement the "5 Dos and 6 Don'ts" epidemic prevention principles in daily life:

"5 Dos": Cook meat and eggs thoroughly with soap; wash hands thoroughly with soap; if symptoms appear, wear a mask, seek medical attention immediately, and inform the doctor of your occupation and contact history; those who have long-term contact with poultry and livestock should get vaccinated against influenza; maintain a balanced diet and exercise appropriately.

"6 Don'ts": Don't eat raw poultry, eggs, or poultry products; don't smuggle or buy meat of unknown origin; don't touch or feed poultry and livestock; don't release or discard poultry and livestock indiscriminately; don't mix poultry and livestock with other poultry and livestock; and don't go to places with poor air circulation or crowded places.

For related information, please visit the Taiwan Centers for Disease Control website (https://www.cdc.gov.tw/) or call the toll-free epidemic prevention hotline 1922 (or 0800-001922).

Source: 

Link: https://www.cdc.gov.tw/Bulletin/Detail/bZE85LXA9ZGdCvEJKZe6Cg?typeid=9

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#Serological #Surveillance of Avian #Influenza Virus #H9N2 Subtype in #Occupational Populations Exposed to #Poultry Environment in #China During 2018–2023

 

Abstract

Background

Avian influenza virus (AIV) H9N2 has a major role in the emergence of influenza pandemic. We assessed the risk of AIV H9N2 to the human population and public health.

Method

The hemagglutination inhibition method was used to screen for hemagglutinin antibodies. Microneutralization tests were performed to confirm neutralizing antibodies against the AIV H9N2 subtype. Real-time polymerase chain reaction was conducted to detect the H9 subtype in environmental samples. GraphPad Prism software was used for mapping, and STATA software was used for statistical analysis.

Results

The nationwide seroprevalence among these populations was 0.76%. Seroprevalence was compared across regions, genders, and occupational exposure sites. The seroprevalence rates for males and females showed no significant difference. Significant differences were found across regions and occupational exposure environments (P < .05). The south and southwest regions had the highest seroprevalence rates at 1.58% and 1.38%, respectively. The highest seroprevalence was observed in individuals exposed to live poultry market (1.51%). Significant regional differences in H9 nucleic acid positive rates (NAPRs) were found (P < .05), with the southwest and central regions showing the highest rates at 25.99% and 24.35%, respectively. H9 NAPR in live poultry markets (LPMs), farms, and slaughterhouses varied significantly by region (P < .05).

Conclusions

Poultry-related environments have become a key factor in AIV H9N2 infection among occupational populations. Exposure to LPM showed the highest seroprevalence among occupational groups. The distribution characteristics of H9N2 across different poultry environments increased the risk of infection in occupationally exposed populations.

Source: 

Link: https://academic.oup.com/ofid/article/13/4/ofag144/8537381

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Clade C #MERS-CoV #camel #strains vary in #protease utilization during viral entry

 

Significance

Clade A/B Middle East Respiratory Syndrome coronavirus (MERS-CoV) outbreaks have caused over 957 deaths since the first spillover in 2012; meanwhile, Clade C strains have been found in camels across Africa but have not yet been reported to cause outbreaks. Investigating why these viruses do not successfully transmit to humans will be key to understanding the pandemic potential of the African MERS-CoV camel reservoir. Our study indicates that clade C viruses exhibit less spike cleavage and that East African clade C isolates are less able to utilize the TMPRSS2 for viral entry of both human cell lines and primary nasal cells. Differences in viral entry pathways could alter cellular and organ tropism and contribute to differential pandemic potential.

Abstract

Middle East Respiratory Syndrome coronavirus (MERS-CoV) is a lethal pathogen with pandemic potential. Clade A and B MERS-CoV viruses have caused outbreaks in the Middle East since 2012 when they initially spilled over from camels to humans. Clade C viruses, however, are only found in camels across Africa and the spillover potential of these viruses seems to be lower than for clade A/B strains but remains to be fully understood. Here, we report that clade C spikes are less well-cleaved at the S1/S2 boundary than clade A or B viral spikes and that most clade C spikes induce reduced syncytium formation. Additionally, we demonstrate that several East African clade C strains are less able to utilize the TMPRSS2-mediated pathway for viral entry in both cell lines and primary nasal epithelial cultures. We map the molecular basis of this reduced TMPRSS2 usage to the N-terminal domain and subdomain 2 of East African clade C MERS-CoV. We suggest that reduced usage of the TMPRSS2-mediated entry pathway may underlie the reduced replication of East African clade C strains in humans, while the reduced replication of West African strains remains to be further investigated. Altered protease usage may contribute to differential tropism of East African clade C strains and indicate geographically distinct selection pressures on spike between MERS-CoV strains circulating in camels.

Source: 

Link: https://www.pnas.org/doi/10.1073/pnas.2525313123

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#Tropism and #Replication Competence of #Cattle #Influenza #H5N1 Genotype B3.13 Virus in #Human Bronchus and #Lung Tissue

 

Abstract

In 2024, influenza A(H5N1) genotype B3.13 viruses emerged from cattle and caused mild spillover infections in humans. Using human bronchus and lung tissue, we evaluated tropism, replication, and pathogenesis of 2 cattle influenza isolates. Those viruses showed moderate replication competence and induced robust proinflammatory responses, suggesting potential risk for human health.

Source: 

Link: https://wwwnc.cdc.gov/eid/article/32/5/25-1926_article

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Avian Influenza Report, Week 13 2026 (#HK SAR CHP, Published on March 31, 2026): One #Human Case of #Infection with #H9N2 #influenza virus in #Italy

 

{Excerpt}

(...)

Avian influenza A(H9N2): 

-- Italy, Lombardy: 

1) An individual with co-existing medical conditions returning from a non-European country. 

- This is the first human case of avian influenza A(H9N2) reported in Europe. 

(...)

Source: 

Link: https://www.chp.gov.hk/files/pdf/2026_avian_influenza_report_vol22_wk13.pdf

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

 

On 26 March 2026, an outbreak investigation team visited a backyard farm following reports of illness and mortality suspected to be caused by Avian Influenza (AI). A total of five samples (three chickens and two ducks) were collected and submitted to NAHPRI/GDAHP for testing of Avian Influenza (H5N1). On 27 March 2026, laboratory results confirmed that three out of five samples (two chickens and one duck) tested positive for Avian Influenza (H5N1). Additionally, in the same area, one human case of Avian Influenza (H5N1) was confirmed by the Ministry of Health on 31 March 2026.

Source: 

Link: https://wahis.woah.org/#/in-review/7409

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