PMID- 20648618
OWN - NLM
STAT- MEDLINE
DCOM- 20101122
LR  - 20100721
IS  - 1096-9071 (Electronic)
IS  - 0146-6615 (Linking)
VI  - 82
IP  - 9
DP  - 2010 Sep
TI  - Quantification of Norwalk virus inocula: Comparison of endpoint titration and 
      real-time reverse transcription-PCR methods.
PG  - 1612-6
LID - 10.1002/jmv.21851 [doi]
AB  - Human noroviruses (NoV) are the leading cause of epidemic acute gastroenteritis. 
      In order to fully characterize features such as persistence and infectious dose, 
      precise quantification of virus concentration is necessary. The purpose of this 
      study was to compare two methods [endpoint titration RT-PCR and quantitative 
      RT-PCR (RT-qPCR)] with respect to quantification of Norwalk virus (NV) in inocula 
      made from purified stock suspensions of human fecal specimens. A full-length NV 
      RNA transcript was developed to facilitate quantification using RT-qPCR and 
      provided log linear detection in the range of 49-4.9 x 10(4) genome equivalent 
      copies (GEC) per reaction. Endpoint titration RT-PCR was used to estimate PCR 
      detection units, and RT-qPCR was used to estimate genome copies in two NV inocula 
      (8fIIa and 8fIIb) used in previous human challenge studies. Overall, RT-qPCR was 
      1.1-1.6 log(10) more sensitive (lower detection limit) than endpoint titration 
      RT-PCR when the same RNA release method, PCR primers and thermocycle program were 
      used. These findings have important implications for many experimental 
      interpretations, not the least of which is estimating the median infectious dose 
      in human challenge studies.
FAU - Liu, Pengbo
AU  - Liu P
AD  - First Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China.
FAU - Hsiao, Hui-Mien
AU  - Hsiao HM
FAU - Jaykus, Lee-Ann
AU  - Jaykus LA
FAU - Moe, Christine
AU  - Moe C
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PL  - United States
TA  - J Med Virol
JT  - Journal of medical virology
JID - 7705876
RN  - 0 (RNA, Viral)
SB  - IM
MH  - Feces/virology
MH  - Gastroenteritis/*virology
MH  - Humans
MH  - Limit of Detection
MH  - Norwalk virus/genetics/*isolation & purification
MH  - RNA, Viral/analysis
MH  - *Reverse Transcriptase Polymerase Chain Reaction
MH  - Sensitivity and Specificity
EDAT- 2010/07/22 06:00
MHDA- 2010/12/14 06:00
CRDT- 2010/07/22 06:00
PHST- 2010/07/22 06:00 [entrez]
PHST- 2010/07/22 06:00 [pubmed]
PHST- 2010/12/14 06:00 [medline]
AID - 10.1002/jmv.21851 [doi]
PST - ppublish
SO  - J Med Virol. 2010 Sep;82(9):1612-6. doi: 10.1002/jmv.21851.