Abstract
We compared Fuji DRI-CHEM IMMUNO AG cartridge flu AB, which utilizes silver-amplified colorless immunochromatography technology, with two other influenza diagnostic kits (kits 1 and 2). We used 131 nasal specimens from outpatients and tested them using RT-PCR. Concerning type A influenza, the positive, negative, and total agreement rates of the silver-amplified immunochromatography system, kit 1, and kit 2 were 100%/96.0%/97.7%, 83.9%/98.7%/92.4%, and 75.0%/100%/89.3%, respectively. Concerning type B influenza, those of the silver-amplified immunochromatography system, kit 1, and kit 2 were 86.7%/98.3%/96.9%, 73.3%/98.3%/95.4%, and 60.0%/99.1%/94.7%, respectively. The silver-amplified immunochromatography system had higher positive agreement rates for types A and B influenzas than the other diagnostic kits. Regarding the patients who reported having a fever of over 38°C, we investigated the relationship between the onset time and the positive agreement rate. The results showed that for the specimens taken within 24 h, the silver-amplified immunochromatography system had a higher positive agreement rate than the other diagnostic kits. The silver-amplified immunochromatography system is highly sensitive; thus, the probability of diagnosing influenza using specimens that contain small amounts of virus is high. We consider that the silver-amplified immunochromatography system is useful for the early diagnosis of influenza, which can help prevent hospital-acquired infections and the spread of influenza in the community.
