Evaluation of rapid immunochromatographic tests for norovirus in neonatal and infant faecal specimens.

Objectives: To compare the diagnostic performance of two norovirus rapid immunochromatographic kits (QuickNavi(®)-Norovirus [QN] and QuickNavi®-Norovirus 2 [QN2]; Denka Seiken, Niigata, Japan) for neonatal and infant faecal specimens.

Methods: Monthly faecal samples were collected from infants from birth to 12 months of age, and tested for norovirus using QN and QN2. Real-time reverse transcription polymerase chain reaction (RT-PCR) was used as the gold standard for norovirus detection. The diagnostic performance of the kits was calculated.

Results: A total of 343 specimens from 81 infants were analysed. In all samples, the specificity of QN and QN2 was 80% (275/343) and 99% (339/343), respectively. In infants aged <1 month, the specificity of QN was 33% (23/70), increasing to 93% at 4 months of age. Specificity of QN2 was ≥94% in infants between 0 and 12 months of age.

Conclusions: QN2 offers improved performance and is more useful than QN for the diagnosis of norovirus infection in the neonatal and infant period.