Dual reverse transcription polymerase chain reaction (RT PCR) detection method for identifying H9N2 subtype avian influenza virus

The invention discloses a dual reverse transcription-polymerase chain reaction (RT-PCR) detection method for identifying an H9N2 subtype avian influenza virus. A pair of primers is designed respectively according to HA genes and NA genes of the H9N2 subtype of avian influenza virus (AIV), the HA genes and NA genes of the H9N2 subtype AIV in a sample can be subjected to specific amplification, and lengths of target fragments are respectively 700bp (HA) and 423bp (NA). According to the method, cross reaction is avoided in subtype AIV such as H3N8, H4N6 and H5N8, Newcastle disease virus and infectious bronchitis virus of chicken; the lowest detection amount of allantoic fluid of the virus is 1*103.25EID50/100uL; compared with conventional methods such as hemagglutination inhibition of virus and a neuraminidase inhibition test, the method has the advantage that the coincidence rate of the identification result is 100 percent. A rapid, specific and sensitive detection means is provided for identifying the H9N2 subtype AIV. The detection method can be used for rapidly diagnosing diseases caused by the H9N2 subtype AIV and has good application prospects in aspects of clinical diagnosis and epidemiological investigation.