Objective  To establish the fluorescence quantitative PCR method for detection of avian influenza virus (AIV) subtypes H7 and H9.   Methods  Primers and probe of fluorescence quantitative PCR were designed for AIV subtypes H7 and H9

respectively

according to the AIV HA H7 and H9 genes. The reaction system and conditions were optimized. Sensitivity

specificity and reproducibility of the system were analyzed.   Results  After optimization of the reaction system and its conditions

the sensitivity of H7 and H9 assay reached 1 10

4.67

EID

50

and 1 10

3.80

EID

50

respectively

and their specificity was similar to that of cell cu

lture. The CV values of CT in intra-and inter-batch were far less than 10%

showing that their reproducibility was excellent.   Conclusion  The sensitivity

specificity and reproducibility of AIV subtypes H7 and H9 are rather good. AIV subtypes H7 and H9 can be used in detection of avian epidemic in suspected avian H7 and H9 infected human cases.