Conclusions
In the current study, a sensitive QD-LFIAS for the simultaneous
detection of influenza A virus subtypes H5 and H9 was developed.
This assay was able to rapidly analyze the sample in one simple
step and yielded objective results via analysis on an inexpensive,
low-maintenance instrument within 15 min. The LODs of QD-
LFIAS for the detection of influenza A virus subtypes H5 and H9
were 0.016 HAU and 0.25 HAU, respectively. Moreover, these two
virus subtypes can be simultaneously detected on only one LFIAS
strip without interferences. The specificity and reproducibility
were both good, and the accuracy was as high as that of real-time
PCR. By changing the conjugation and capturing antibody pairs,
this system can be conveniently extended to detect other types of
pathogens. Overall, the QD-LFIAS is a sensitive method to rapidly
detect influenza A virus subtypes H5 and H9 and may be used for
diagnosis in field tests.