H9n2 Avian Influenza Virus ns1 gene deletion candidate live attenuated vaccine strain and its construction method and application

The present invention relates to H9N2 avian influenza virus NS1 gene deletion candidate live attenuated vaccine strain rTX-NS1-128 constructing method and application. The H9N2 subtype avian influenza virus NS1 gene deletion candidate live attenuated vaccine strain rTX-NS1-128, is A / chicken / Taixing / 10 / 2010TX female parent strain, the length of the NS1 gene is deleted, such that the NS1 protein retaining only shown in SEQ ID NO.15 as 128 amino acids. The vaccine candidate can be copied in the trachea, contact transmission occurs, safety. The candidate vaccine strain can be used alone as an effective tool H9 subtypes of avian influenza, can also be used in combination with inactivated vaccine, provide a more exact immune protection. It will play a very important role in H9 subtype of avian influenza prevention and control.