Swayne D E, Sims L D, Brown I, Harder T, Stegeman A, Abolnik C, Delgado M, Awada L, Pavade G, Torres G
Rev Sci Tech. 2024 Dec;Special Edition:89-102. doi: 10.20506/rst.SE.3563.
H5Nx A/Goose/Guangdong/1/96 Eurasian lineage high pathogenicity avian influenza (HPAI) viruses have been the main HPAI strains detected globally since 2005. These have spread around the world, causing a panzootic that has spanned six continents, with continual threat to not only wild and captive birds and poultry, but also wild, captive and domestic mammals and humans. The viruses' ecology and epidemiology - especially the 2.3.4.4b clade - have changed, with over 489 species of birds infected and spreading the virus over migratory routes. This results in the death of many birds, including endangered species, and serves as a source of transmission to poultry and mammals. Improved surveillance and sharing of HPAI virus sequences, metadata and viruses across the veterinary, public health, wildlife and environment sectors are needed to elucidate the population dynamics of the infections, which is crucial to addressing this complex One Health issue. The development of appropriate mitigation strategies or changes in husbandry, production and selling practices can reduce the risk of viruses being introduced into farms, as well as their amplification and viral evolution, and any spill-back to wild birds. Approaches to prevention and control of HPAI in countries where these 2.3.4.4b viruses remain entrenched in poultry, or places at risk of virus introduction via wild bird populations, involve measures to reduce the effects of the disease in poultry (including enhanced farm bio-security, vaccination, zoning and compartmentalisation). Their uptake reflects the difficulties encountered in relying solely on biosecurity for disease prevention and on stamping out alone for virus control and elimination. The World Organisation for Animal Health's Terrestrial Animal Health Code allows use of vaccination of poultry under specific conditions and without negatively impacting HPAI-free status if appropriate surveillance is conducted, thus supporting safe trade in poultry and poultry products. Nevertheless, concerns regarding loss of valuable export markets still interfere with greater utilisation of vaccination.
自2005年以来，H5Nx A/鹅/广东/1/96欧亚谱系高致病性禽流感（HPAI）病毒一直是全球检测到的主要HPAI毒株。这些病毒已传播至世界各地，引发了一场跨越六大洲的大流行，不仅对野生和圈养鸟类及家禽构成持续威胁，对野生、圈养和家养哺乳动物以及人类也构成威胁。病毒的生态学和流行病学，尤其是2.3.4.4b分支，已经发生变化，超过489种鸟类感染该病毒并通过迁徙路线传播。这导致许多鸟类死亡，包括濒危物种，并成为向家禽和哺乳动物传播的源头。需要加强兽医、公共卫生、野生动物和环境部门之间对HPAI病毒序列、元数据和病毒的监测与共享，以阐明感染的种群动态，这对于解决这一复杂的“同一个健康”问题至关重要。制定适当的缓解策略或改变饲养、生产和销售方式，可以降低病毒传入养殖场的风险，以及病毒的扩增和进化，以及任何向野生鸟类的反向传播。在这些2.3.4.4b病毒在家禽中仍然根深蒂固的国家，或有通过野生鸟类种群引入病毒风险的地方，预防和控制HPAI的方法包括采取措施减少该疾病在家禽中的影响（包括加强农场生物安全、疫苗接种、分区和分区域管理）。这些措施的采用反映出仅依靠生物安全进行疾病预防以及仅依靠扑杀进行病毒控制和根除所面临的困难。世界动物卫生组织的《陆生动物卫生法典》允许在特定条件下对家禽进行疫苗接种，并且如果进行适当监测，不会对无HPAI状态产生负面影响，从而支持家禽和家禽产品的安全贸易。然而，对失去宝贵出口市场的担忧仍然妨碍了疫苗接种的更广泛应用。
