Journal of Clinical Virology - Volume 82 - Supplement 1 - September 2016

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S60 Abstracts / Journal of Clinical Virology 82S (2016) S1–S142
guidelines and establish an agreement with European reference
BSL-4 laboratories for additional tests.
Abstract no: 111
Presentation at ESCV 2016: Poster 78
Norovirus genotypes diversity in sporadic cases
and in outbreaks of acute gastroenteritis in
Spain: A 10-year study
Susana Vila-Vicent ∗, Cristina Santiso-Bellón,
Manuel Fernández-Jiménez,
Noelia Carmona-Vicente, Jesús Rodríguez-Díaz,
Javier Buesa
University of Valencia, Spain
Introduction: Human norovirus (NoV) is a major cause of viral
acute gastroenteritis worldwide. NoV causes sporadic cases and
outbreaks of acute gastroenteritis (AGE), often in health care sett-
ings (including hospitals and elderly care homes), where the virus
is predominantly spread from person to person. Most human NoVs
belong to genogroups GI and GII, with more than 30 genotypes. The
transition of endemic to epidemic NoV genotypes remains poorly
understood. Despite the great genetic diversity among NoVs, a sin-
gle genotype, GII.4, further subdivided into ‘variants’, is responsible
for the majority of the NoV outbreaks worldwide. The aim of this
study was to analyse the temporal distribution and variation of
NoV strains causing sporadic cases and outbreaks of AGE during a
decade, taking into account that NoV infections are clearly under-
diagnosed.
Materials and methods: A total of 1610 stool samples from
sporadic cases and outbreaks of AGE were analysed by RT-PCR
targeting the RNA polymerase with primers JV12/JV13 and even-
tually with primers G1SKF/G1SKR or G2SKF/G2SKR for capsid gene
amplification. RNA was extracted from stool samples with Trizol
reagent (Life Technologies). NoV was detected by ORF1 (poly-
merase) and/or ORF2 (capsid gene) RT-PCR. Genotypingwas carried
out by sequencing PCR amplicons, 114 obtained from outbreak
specimens and 253 from sporadic case specimens. Genotypes were
identified by using the BLAST program and by the NoV automated
genotyping tool .
Results: NoV strains causing outbreaks along the 10 years ana-
lysed in this study have evolved in a sequential manner, starting
in 2006 with GII.4 Den Haag 2006b variant, followed thereafter by
GII.4 New Orleans 2009 and by GII.4 Sydney 2012. In the last year
a new genotype, GII.17, has arisen for the first time causing out-
breaks. Sporadic cases of NoV gastroenteritis were caused by the
same strains during their circulation periods, as well as by many
other genotypes regarded as non-epidemic: GI.1, GI.2, GI.3, GI.4,
GI.7, GI.9; GII.1, GII.2, GII.3, GII.4 Apeldoorn 2007, GII.4 2010, GII.7,
GII.12, GII.13, GII.16, GII.17, GII.21 and GIV.
Conclusions: The temporal distribution of NoV genotypes is
very dynamic and difficult to predict according to the historical
data recorded by our laboratory and by others. Norovirus genotype
surveillance is necessary to detect the emergence of new strains.
Abstract no: 130
Presentation at ESCV 2016: Poster 79
Detection and characterisation of viral
pathogens causing gastroenteritis in Ireland,
2014–2016
Z. Yandle ∗, G. Tuite, S. Coughlan, J. O’Gorman,
C. De Gascun
National Virus Reference Laboratory, University
College Dublin, Dublin, Ireland
Background: The National Virus Reference Laboratory (NVRL)
receives ∼12,000 faecal samples a year from patients presenting
with suspected viral gastroenteritis (VGE) in Ireland. All sam-
ples are tested for norovirus, rotavirus, sapovirus, astrovirus and
enteric adenovirus. We present two years data from the VGE
screen. Rotavirus vaccination will be included in the national infant
immunisation schedule in Ireland from the 1st October 2016. The
NVRL offers a rotavirus genotyping service and the data generated
will determine a baseline of circulating strains in Ireland and will
monitor the genetic evolution post implementation of vaccination.
The NVRL also contributes to the surveillance of norovirus by genet-
ically characterising circulating strains to monitor the changing
epidemiology of the viral genotypes.
Methods: An in-house real time PCR was developed and vali-
dated to detect the five main causes VGE. The genotyping method
was a WHO PCR method of the VP7 and VP4 regions and elec-
trophoresis to determine the G and P genotype. The genetic analysis
of the norovirus was performed using Sanger sequencing.
Results: Seasonal trends of the five viruses were observed
as expected. In 2015, circulation of viruses associated with VGE
peaked in February andMarch. In February 2015 the NVRL received
1218 samples for testing. Of these 239 (20%) were positive for
norovirus and 146 (12%) were positive for rotavirus. InMarch 2015,
1404 sampleswere received; 213 (15%) and 183 (13%)were positive
for norovirus and rotavirus respectively. In 2016 the VGE season
peaked a month later than in 2015. In March 2016, 1366 samples
were tested and were norovirus positive in 277 (20%) of samples
and rotavirus in 63 (5%) of samples. In April 2016, 1416 samples
were tested and 247 (17%) and 115 (8%) were detected as norovirus
and rotavirus respectively. The remaining viruses were detected
at lower levels; sapovirus and astrovirus were more dominant in
the winter months whereas enteric adenovirus demonstrated no
obvious seasonal trend. Approximately 3% of the positive samples
contained more than one virus, the most common combination
being norovirus and rotavirus. In addition to norovirus causing out-
breaks of VGE, we found that rotavirus and sapovirus have been
responsible for outbreaks within the paediatric and elderly popula-
tion. The commonest strain of norovirus circulating was Norovirus
GII which accounted for 90% of norovirus cases. Phylogenetic analy-
sis of a representative number of norovirus outbreaks and sporadic
cases performed in 2014/2015 season, identified viruses clustering
with GI.3, GII.1 GII.3, GII.4 and GII.6 strains. The recently described
new variant of GII.17 was not detected in this season. To date
52 rotavirus positive samples have been genotyped. The most
commonly detected strains were G9P[8] (40%) and G1P[8] (33%);
followed by G4P[8] and G2P[4] (19% and 8% respectively).
Conclusion:The predominant virus detected in suspected cases
of VGEwas norovirus in both adults and children. This was followed
by rotavirus, sapovirus, astrovirus and then enteric adenovirus.
The rotavirus genotyping results indicate that the rotavirus strains
detected in Ireland reflect those that are circulating in other Euro-
pean countries. Interestingly there appears to be larger proportion
of G9P[8] in Ireland than reported in other countries. As in previous