{"id":85428,"date":"2025-04-04T09:32:48","date_gmt":"2025-04-04T02:32:48","guid":{"rendered":"https:\/\/www.medion.co.id\/?p=85428"},"modified":"2025-07-16T13:43:09","modified_gmt":"2025-07-16T06:43:09","slug":"waspada-peningkatan-kasus-avian-influenza","status":"publish","type":"post","link":"https:\/\/www.medion.co.id\/en\/info-medion\/be-alert-to-the-rising-cases-of-avian-influenza\/","title":{"rendered":"Be Vigilant Against the Increasing Cases of Avian Influenza"},"content":{"rendered":"

Indonesia\u2019s tropical climate provides a favorable environment for pathogens to thrive. Weather conditions significantly influence the pattern of diseases that occur in poultry farms. High humidity during the rainy season, transitional periods, and humid dry seasons can trigger the rapid growth and spread of disease-causing agents. Unstable weather changes may also cause stress in chickens, making them more susceptible to infections.<\/p>\n\n\n\n

Similarly, the trend of Avian Influenza (AI) outbreaks often emerges during the rainy season and transitional periods. This condition requires farmers to be more alert and meticulous regarding disease attacks and field handling, considering that the losses caused by AI are quite substantial. These include high mortality and morbidity rates, a decline in egg production of up to 40%, a high culling <\/em>rate, increased treatment and disinfection costs, and heightened susceptibility to other diseases.<\/p>\n\n\n\n

AI Disease Trend in the Field<\/h2>\n\n\n\n

Since it was first identified in Indonesia at the end of 2003, cases of Avian Influenza (AI) have continued to be found in poultry farms, including broilers (broiler<\/em>), layers (layer<\/em>), breeders (breeder<\/em>), roosters, local crossbreeds (joper<\/em>), ducks, quails, and other poultry species. As of 2024, AI cases are predominantly found in layer chickens, as shown in Graph 1.<\/p>\n\n\n\n

Based on data from Medion Disease Incidence<\/em> in 2024, Avian Influenza (AI) cases increased during the rainy season, particularly at the beginning and end of the year. As shown in Graph 1, the number of cases rose in January, February, and December. It is also noteworthy that while AI cases were initially more prevalent during the rainy season, recent data indicate a rise in cases during the dry season. As illustrated in Graph 2, there was an increase in AI cases in June and July.<\/p>\n\n\n\n

The increase in cases, particularly among layer chickens, may be attributed to high internal stress levels, especially during the early to peak production stages \u2014 a critical phase in layer management. During this period, if the chickens experience external stress due to poor biosecurity<\/em> practices and inadequate farm management, it can facilitate the entry and infection of diseases, including Avian Influenza (AI). Such stress conditions have an immunosuppressive effect, which negatively impacts the birds\u2019 immune response and antibody titers.<\/p>\n\n\n\n

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Avian Influenza (AI) can occur at any stage of poultry rearing. In layer chickens, AI cases have been detected in both young and adult birds. The number of cases tends to increase after 18 weeks of age and is predominantly observed during the production period between 28 and 55 weeks (Graph 3). In broilers, AI cases are most common at 3\u20135 weeks of age but can also occur in birds older than 5 weeks (Graph 4).<\/p>\n\n\n\n

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Nationally, Avian Influenza (AI) in layer chickens during the production period ranks second among viral diseases from 2023 to 2025. As shown in Graph 5, the incidence rate remains quite high, second only to Newcastle Disease (ND). The persistently high ranking of AI cases deserves serious attention, especially considering the significant economic losses caused by this disease.<\/p>\n\n\n\n

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Avian Influenza (AI) is known as an immunosuppressant<\/em> disease, meaning it weakens the bird\u2019s immune system and makes it easier for other pathogens to infect the flock. The following data present cases of AI occurring alone or in combination with other diseases.<\/p>\n\n\n\n

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Based on the compiled data of AI cases in layer farms from 2024 to January 2025 (Graph 6), single AI infections accounted for 36% to 50% of the total cases. The remaining cases involved co-infections (coinfections) with other disease agents. The highest AI co-infection rates occurred alongside bacterial and viral diseases, followed by cases involving parasitic and fungal infections. AI can also coexist with non-infectious conditions such as mycotoxicosis and heat stress<\/em>.<\/p>\n\n\n\n

Evolution of the Avian Influenza Virus<\/h2>\n\n\n\n

As is widely known, Avian Influenza (AI) is caused by the Orthomyxoviridae<\/em> virus, a single-stranded RNA virus that is enveloped, making it sensitive to all types of disinfectants. The incubation period of AI is relatively short, ranging from a few hours to three days.\n\nThe AI virus possesses important surface proteins that determine its subtype, classified into 18 hemagglutinins\/HA (H1 to H18) and 11 neuraminidases\/NA (N1 to N11). The HA protein functions in hemagglutination activity\u2014facilitating the attachment of the virus to the host cell receptor and enabling fusion with the cell membrane\u2014while the NA protein plays a role in degrading and releasing the virus from the host cell receptor.<\/p>\n\n\n\n

The first case of Avian Influenza (AI) in Indonesia was detected in 2003. That year, the AI H5N1 clade<\/em> 2.1 strain was identified, followed by the detection of AI H5N1 clade<\/em> 2.3.2.1c in 2012. In 2016, the AI H9N2 strain was reported, and the most recent detection of AI H5N1 clade<\/em> 2.1 also occurred in the same period.\n\nBased on its pathogenicity, AI H5N1 is classified as High Pathogenic Avian Influenza<\/em> (HPAI) due to its high virulence, whereas AI H9N2 is categorized as Low Pathogenic Avian Influenza<\/em> (LPAI) because of its lower virulence level.\n\nIn 2019 and 2021, the AI H5N1 clade<\/em> 2.3.2.1c strain underwent mutations\u2014specifically changes in key viral proteins, Hemagglutinin<\/em> and Neuraminidase<\/em>\u2014which altered its characteristics over time.\n\nIn 2022, a new AI H5N1 clade<\/em> 2.3.4.4b strain was detected for the first time in Indonesia at a commercial duck farm in South Kalimantan, where no AI vaccination had been implemented. From 2022 to 2024, the dominant circulating strains have been AI H5N1 clade<\/em> 2.3.2.1c and AI H9N2 lineage<\/em> Y280.<\/p>\n\n\n\n

In 2024, there was a change in the nomenclature of Avian Influenza (AI) viruses in Indonesia based on the HA H5 gene classification by OFFLU Avian Influenza Matching (OFFLU AIM). The strain previously known as H5N1 clade<\/em> 2.3.2.1c was reclassified as H5N1 clade<\/em> 2.3.2.1g.\n\nAs of 2025, the circulating AI subtypes in Indonesia are H5N1 and H9N2, with the number of H5N1 cases remaining higher than that of H9N2 (Graph 7). According to data from Medion\u2019s Surveillance Analyst<\/em>, from 2024 to March 2025, H5N1 clade<\/em> 2.3.2.1c remains the most dominant strain detected.\n\nMeanwhile, the circulating H9N2 virus in Indonesia, based on the HA H9 gene, still belongs to the B lineage<\/em> (Y280), clade<\/em> h9.4.2.5. Genetically, this H9N2 strain remains consistent with the variant first identified in Indonesia.<\/p>\n\n\n\n

The mutative nature of the Avian Influenza (AI) virus must always be treated with caution. Mutations in either the HA or NA proteins of the AI virus can increase the risk of vaccine failure. To anticipate such developments, Medion remains actively engaged in continuous monitoring<\/em> and surveillance<\/em> of AI-related cases across various regions in Indonesia.<\/p>\n\n\n\n

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Clinical Symptoms and Pathological Changes<\/h2>\n\n\n\n

The clinical signs and anatomical pathology observed in chickens infected with different clades<\/em> of AI H5N1 are very similar, making it difficult to distinguish between them based solely on these indicators. To accurately differentiate between clades<\/em>, supporting diagnostic tests are required, specifically laboratory analyses. These examinations are further extended to the molecular biology stage using the Polymerase Chain Reaction<\/em> (PCR) and sequencing<\/em> methods.\n\nBelow are examples of clinical signs and anatomical pathology changes observed in AI cases, particularly H5N1. However, these symptoms do not always appear completely or clearly in every case. Their manifestation can also be influenced by the chicken\u2019s immune status (including vaccination history), the implementation of biosecurity<\/em> measures, and the overall management practices at the farm.<\/p>\n\n\n\n

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Chickens appear weak and pale.<\/figcaption><\/figure>\n<\/div>\n\n\n\n
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Bluish discoloration of the comb.<\/figcaption><\/figure>\n<\/div>\n\n\n\n
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Reddish-purple discoloration on the legs.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n
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Inflammation of the heart fat (pericardial fat inflammation).<\/figcaption><\/figure>\n<\/div>\n\n\n\n
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Inflammation of the abdominal fat.<\/figcaption><\/figure>\n<\/div>\n\n\n\n
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Dilation of the brain blood vessels.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n
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Inflammation of the ovary.<\/figcaption><\/figure>\n<\/div>\n\n\n\n
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Kista oviduct<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n
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Swollen kidneys.<\/figcaption><\/figure>\n<\/div>\n\n\n\n
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Inflammation of the proventriculus.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n

Diagnosis of Avian Influenza (AI) must be carried out comprehensively. It begins with an anamnesis examination, gathering vaccination history, observing clinical symptoms, and performing necropsy to assess anatomical pathology changes as a basis for diagnostic direction. The diagnosis is then confirmed through laboratory testing. The Hemagglutinin Inhibition<\/em> (HI) test can serve as an alternative method, but greater accuracy is achieved through PCR and sequencing<\/em> analyses.<\/p>\n\n\n\n

Avian Influenza (AI) Disease Control<\/h2>\n\n\n\n

Efforts to prevent and control Avian Influenza (AI) in poultry farms should include the proper implementation of a vaccination program, combined with strict sanitation and biosecurity<\/em> measures, as well as supplementation to enhance the birds\u2019 immune resistance.<\/p>\n\n\n\n

Sanitation and Biosecurity<\/em><\/h3>\n\n\n\n