ETIDIOH - NEW

  • New human cases {1,2}:  -- From 30 September to 5 November 2025 , based on reporting date, the detection of influenza A(H5N1) in one human , A( H5N2 ) in one human and A( H9N2 ) in two humans were reported officially.   • Circulation of influenza viruses with zoonotic potential in animals :  -- High pathogenicity avian influenza (HPAI) events in poultry and non-poultry animal species continue to be reported to the World Organisation for Animal Health (WOAH).{3}  -- The Food and Agriculture Organization of the United Nations (FAO) also provides a global update on avian influenza viruses with pandemic potential.{4}  • Risk assessment {5}:  -- Sustained human to human transmission has not been reported in the above human infection events.  -- Based on information available at the time of this risk assessment update , the overall public health risk from currently known influenza A viruses detected at the human-animal interface has not changed...

  Summary -- What is already known about this topic? - A total of 117 H9N2 cases of human infection of Chinese origin had been reported to the World Health Organization (WHO) by May 9, 2025, with 22 of them originating in Hunan Province. -- What is added by this report? - This article reported on the investigation of three new H9N2 avian influenza virus (AIV) infections detected in Changsha, Hunan Province , in April 2025. No epidemiological link was found among them. Exposure to live poultry was identified as the primary risk factor for infection. Sequence analysis of the three H9N2 AIVs showed a similarity of 99.71%–99.82% between hemagglutinin (HA), and the homology of the neuraminidase (NA) genes was 98.41%–99.83%. Although the tests showed that the HA had enhanced binding ability to upper respiratory tract cells’ receptors , no evidence of sustained human-to-human transmission has been found so far. -- What are the implications for public health practice? - This study indicate...

{Excerpt} This Week : [Date of report - Country - Province / Region District / City - Sex - Age - Condition at time of reporting  - Subtype of virus] 1) .../10/2025 - Cambodia - Takeo Province - F - 14 - Hospitalised - H5N1  2) 16/10/2025 - Cambodia - Kampong Speu Province - F - 3 - Under intensive care - H5N1 (...) [Place of occurrence - No. of cases  (No. of deaths) - Details] -- Bangladesh - 1(0)  - Avian influenza A(H5) :  1) Sylhet Division : A boy with onset on July 27, 2025.  -- Chinese Mainland - 4(0)  - Avian influenza A( H9N2 ):  - Guangdong Province :  1) An individual with onset in February 2025. The case was retrospectively reported.  - Guangxi Zhuang Autonomous Region :  2, 3) Two individuals with onset in February 2025. Both cases were retrospectively reported.   - Tianjin Municipality :  4) An individual with onset in February 2025. The case was retrospectively reported.  -- Mexico - 1(0)  - ...

  Highlights --  We conducted surveillance for influenza A viruses at live bird markets in northern Vietnam. --  Six different subtypes of influenza A virus were found co-circulating in the markets. --  Notable genetic mutations were found across many genes. --  These markets have great potential to generate new pandemic influenza A virus strains. Abstract Objectives Live bird markets (LBMs) in Asia have often been the source of human infections with avian influenza virus (AIV). Methods From July 2021 to August 2023, we employed a One Health approach in conducting periodic surveillance for novel influenza A viruses in five LBMs in northern Vietnam. Specimens were studied with egg culture, molecular assays, Sanger sequencing, and next-generation sequencing. Results We studied a total of 688 human, avian, and bioaerosol specimens . Among these, 118 ( 17.2% ) were found to have molecular evidence of AIVs . Next-generation sequencing of 92 isolates revealed multiple...

  New human cases {1,2}:  -- From 26 August to 29 September 2025 , based on reporting date, the detection of influenza A(H5) in one human , influenza A(H5N1) in one human , influenza A(H9N2) in eight humans and an influenza A(H1N1) variant ((H1N1)v) virus in one human were reported officially.   Circulation of influenza viruses with zoonotic potential in animals :  -- High pathogenicity avian influenza (HPAI) events in poultry and non-poultry animal species continue to be reported to the World Organisation for Animal Health (WOAH).{3}  -- The Food and Agriculture Organization of the United Nations (FAO) also provides a global update on avian influenza viruses with pandemic potential.{4}  Risk assessment {5}:  -- Sustained human to human transmission has not been reported from these events.  -- Based on information available at the time of this risk assessment update , the overall public health risk from currently known influenza A viruses d...

  Abstract The poultry industry faces a constant threat from the mutation and transmission of avian influenza viruses (AIVs). While waterfowl and wild birds are natural hosts of H3N3 AIV , reports of H3N3 infections in chickens are limited. However, in 2023, a decline in egg production among laying hens in the Yancheng Region of Jiangsu Province prompted a study. This research aimed to diagnose the aetiology in laying hens through molecular virological methods and characterise the biological properties of the causative pathogens. An H3N3 AIV subtype strain, A/chicken/China/YC01/2023(H3N3), was isolated from chickens exhibiting lesions. Genome sequencing and analysis revealed a novel genetic makeup : the HA gene originated from an H3N8 AIV, the NA gene from an H10N3 AIV, and the internal genes from an H9N2 AIV, all circulating in China. Chickens experimentally infected with the isolate showed signs of Harderian gland haemorrhage, nasal mucus, tracheal circumferential bleeding , and ...

  New human cases {1,2}:  -- From 2 July to 25 August 2025 , based on reporting date, the detection of influenza A( H5N1 ) in five humans and influenza A(H9N2) in two humans were reported officially.   Circulation of influenza viruses with zoonotic potential in animals :  - High pathogenicity avian influenza (HPAI) events in poultry and non-poultry animal species continue to be reported to the World Organisation for Animal Health (WOAH).{3}  - The Food and Agriculture Organization of the United Nations (FAO) also provides a global update on avian influenza viruses with pandemic potential.{4}  Risk assessment {5}:  - Sustained human to human transmission has not been reported from these events.  - Based on information available at the time of this risk assessment update , the overall public health risk from currently known influenza A viruses detected at the human-animal interface has not changed and remains low .  - The occurrence of sus...