TABLE 1.

Summary of norovirus detection by conventional and real time RT-PCR in clinical stool specimens from PLPH, Canada, and CDC, Atlantaa

SamplesSpecimens from CDCSpecimens from PLPH
Original result from CDCConventional RT-PCR assay for norovirusLightCycler real-time RT-PCR for norovirusOriginal result from PLPHLightCycler real-time RT-PCR for norovirus
PositiveNegativePositiveNegativePositiveNegativePositiveNegativePositiveNegative
Positive for norovirus G-II by conventional RT-PCR at CDC or PLPH (n = 62)a1812617144440
    G-II/111010
    G-II/222020
    G-II/343131
    G-II/422020
    G-II/621120
    G-II/710110
    G-II/1021120
    G-II/1211010
    G-II/1521120
    G-II/1610110
Positive for norovirus G-I by conventional RT-PCR at CDC or PLPH (n = 4)b4NTeNT40
    G-I/12NTNT20
    G-I/21NTNT10
    G-I/31NTNT10
Negative for norovirus by conventional RT-PCR at CDC or PLPH (n = 56)c2021861436531
Positive for other enteric viruses (n = 10)d20202808
    Sapovirus20202202
    Rotaviruses202
    Astroviruses202
    Adenoviruses202
  • a The 62 G-II-positive samples included 18 outbreak samples and 27 outbreak samples previously tested by conventional RT-PCR at CDC and PLPH, respectively, as well as 17 samples that were collected from children with sporadic gastroenteritis and tested side by side with conventional and real time RT-PCR. For each sample category with columns of lightface numbers, the boldface number at the top of each column represents the total of the lightface numbers listed below it.

  • b The four G-I-positive samples were provided by CDC.

  • c The 56 samples included 20 outbreak samples that previously tested negative by conventional RT-PCR at CDC and 36 samples that were collected from children with sporadic gastroenteritis and tested side by side with conventional and real time RT-PCR. A total of 11 samples tested positive by real time RT-PCR.

  • d The 10 samples were positive for other viruses, including four sapoviruses (two from CDC and two from PLPH), and each two rotaviruses, astroviruses, and adenoviruses (from PLPH).

  • e NT, not tested.