Low pathogenicity avian influenza (LPAI) H9N2, highly pathogenic avian influenza (HPAI) H5N1, and H5N8 circulate in Egyptian poultry and cause veterinary and public health burdens. In response, AIV vaccines are commonly used. The main objective of this study was to develop a broad, cross-protective, trivalent vaccine based on circulating AIVs in Egypt. We generated highly replicating avirulent AIVs, H5N1, and H5N8, to be used in combination with H9N2 strain for the generation of an inactivated vaccine. Immunogenicity and protective efficacy of this vaccine were tested. Results showed that a single immunization dose enhanced humoral immune responses giving full protection against challenges with LPAI H9N2, HPAI H5N1, and H5N8 viruses. This efficacious vaccine will reduce the cost of vaccination for poultry growers and is expected to be effective in the field as it is based on contemporary viruses currently in circulation among Egyptian poultry.

中文翻译：

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针对埃及流行的H5N1，H5N8和H9N2的有效当代三价禽流感疫苗的开发。

低致病性禽流感（LPAI）H9N2，高致病性禽流感（HPAI）H5N1和H5N8在埃及家禽中传播，并给兽医和公共健康造成负担。作为响应，通常使用AIV疫苗。这项研究的主要目的是开发一种基于埃及循环AIV的广泛的，具有交叉保护作用的三价疫苗。我们生成了高度复制的无毒AIV，H5N1和H5N8，将其与H9N2菌株结合使用以生成灭活疫苗。测试了该疫苗的免疫原性和保护功效。结果表明，单次免疫剂量可增强体液免疫反应，从而完全抵抗LPAI H9N2，HPAI H5N1和H5N8病毒的攻击。