Norovirus Testing:
What Happens at “The Lab”
Dr. Amy Woron
Amy.Woron@TN.gov
615-262-6462
Molecular Biologist
TN Dept. of Health
Laboratory Services
Norovirus GI and GII Assay
• Differentiates between GI and GII
• Can have results in as little as 5 hours
2009 data below
GI
GII
GI pos
GII pos
GI and GII pos
TN Grand
Region
County
GI
pos
GII
pos
East
Hamilton
5
9
East
Henderson
2
East
Knox
1
Middle
Davidson
1
5
Middle
Robertson
1
1
Middle
Sumner
1
5
Middle
Williamson
3
Middle
Wilson
2
West
Gibson
1
Out of State
N/A
2
GI and
GII pos
1
CaliciNet
• There are multiple patients all with
norovirus GII.
• Are they all related?
CaliciNet USA
• Best tool is the epi investigation …..
• CaliciNet can help
National Norovirus Outbreak Network
Current Pitfalls in Norovirus
Surveillance
• No national laboratory surveillance
system
– Tracking multi-state (international) outbreaks
with a potential common source is a
challenge
– Only a fraction of the states report to the
CDC
• No standard protocol among laboratories
for sequence analysis and genotyping
Objectives of CaliciNet
• Improve surveillance of norovirus
(sapovirus, other GI viruses)
• Allow for real-time data exchange at the
state and national level
• Rapid genotyping and compare norovirus
sequences
• Link geographically different clusters of
illness to a common (food) source
• Facilitate the identification of new
emerging norovirus strains
States Participating in CaliciNet
WA
MT
OR
ME
ME
ME
ND
MN
ID
VT
NH
SD
RI
MI
PA
IA
NE
NV
OH
UT
MD
MD
IN
CO
CA
MA
NY
WI
WY
IL
KS
WV
MO
VA
KY
NC
TN
OK
AZ
AR
SC
NM
MS
HI
TX
AL
GA
LA
AK
FL
FL
States with CaliciNet certified participants March 2010 (n = 16)
CT
NJ
DE
DC
Confirmed and Suspected Etiology of 1270
Foodborne Outbreaks Reported to CDC, 2006
Other/Multiple
2%
Unknown
29%
Norovirus
40%
Chemical
5%
Parasites
1%
CDC 2009
MMWR
Bacteria
23%
Norovirus testing:
From Stool Cup to Sequence
RT-PCR testing
Stool specimen
RNA
Extraction
positive
Real-time RT-PCR
Conventional RT-PCR
Compare norovirus sequence
with database
Cycle sequencing
Norovirus regions targeted by detection
and typing RT-PCR assays
Hel
Pro
Pol
VP2
VP1
5' 1
ORF 3
ORF 1
ORF 2
RT*
C
85/98 bp 330/344 bp
* RT = TaqMan realtime
RT-PCR
D
177/253 bp
Norovirus detection Norovirus typing
7654
3'
Required fields for CN upload
Epi
Page 8; CN Manual v.3
Lab
Multiple Alignment
Dendrogram
Nucleotide Polymorphisms
GI
Reference
Strains
GII
Reference
Strains
Similarity to PulseNet
•
•
•
•
BioNumerics
Encourage state level participation
Increase real-time information flow
Ability to view/compare outbreaks at the
national level
• Another tool in the epidemiology tool
belt
CaliciNet Summary
– A novel national surveillance system for
linking norovirus outbreak clusters
potentially to a common source
– Network for standardized norovirus
genotyping and classification
– Potential to identify new emerging
norovirus strains
CDC CaliciNet Team Contact information:
Leslie Barclay lbarclay@cdc.gov (CaliciNet scripts)
Nicole Gregoricus ngregoricus@cdc.gov (Laboratory protocols)
Jan Vinjé jvinje@cdc.gov (Supervisor CaliciNet)
Future Study
• Human Astrovirus testing …
• Human Sapovirus testing …
• Food testing for norovirus …
Slides with the CDC CaliciNet logo courtesy
of Dr. Jan Vinjé, CaliciNet Team Leader, CDC
Questions?