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

18 / 152

S14 Abstracts / Journal of Clinical Virology 82S (2016) S1–S142
lymphocyte counts. A significant correlation was found between
the TTV DNA load and the number of CD4+ and CD8+ T cells on
day 30 ( Spearman 0.68 and 0.71, respectively, P= 0.001). Notably,
there was a strong correlation between plasma TTV DNA load and
CMVpp65 and IE-1-specific IFN- -producing CD4+ and CD8+ T cells
on day 30 ( Spearman 0.80 and 0.58, respectively, P= 0.003). In
fact, ROC analyses showed that a cutoff of 3.90 log10 of TTV viremia
predicted the reconstitution of CMV-specific CD8+ T cells at levels
>1 cell/ L (previously shown to be protective from the occurrence
of CMV DNAemia) with a PPV of 75% and a NPV of 86.6% (P = 0.006).
Conclusion: Plasma TTV DNA load may serve as a surrogate
marker for reconstitution of the CMV-specific CD8+ T-cell response.
Larger studies are nevertheless needed to draw definitive conclu-
sions on this issue.
Abstract no: 229
Presentation at ESCV 2016: Oral 25
Whole-genome sequencing of adenovirus in
immunocompromised paediatric patients
directly from clinical samples elucidates
molecular epidemiology of suspected outbreaks
C.J. Houldcroft ∗, D.P. Depledge , R. Williams ,
E. Cloutman-Green Standing reuer
1 University College London Institute of Child Health,
United Kingdom
2 University College London, United Kingdom
3 Great Ormond Street Hospital for Children, United
Kingdom
Background: Adenoviruses are significant pathogens for the
immune supressed, with 15% of paediatric bone marrow transplant
(BMT) recipients experiencing adenovirus reactivations. Adenovi-
raemia post-BMT is associated with increased treatment costs,
longer hospital stays, and increased morbidity and mortality.
Whole-genome sequencing of adenovirus provides a wealth of
clinically relevant information on genome variation, including
phylogeography, resolution of locally circulating subtypes and
improved molecular epidemiology, the capacity to identify new
recombinant subtypes, and mutation data in response to antivi-
ral drug selection pressure. Adenovirus-positive clinical specimens
from patients at Great Ormond Street Hospital for Children include
isolated and suspected outbreak cases.
Methods: We retrospectively identified 90 adenovirus positive
residual diagnostic samples (including blood, urine, swabs (eye,
throat and unspecified), ascetic fluid and endo-tracheal aspirate)
with virus loads greater than 5 ×104 copies/ml from 30 patients
treated at Great Ormond Street Hospital (GOSH) collected between
1st January 2015 and 30th April 2016. Additional samples from a
suspected outbreak of adenovirus at GOSH in 2011/2012 and three
cultured reference strains (D9, E4 and F40)were also sequenced and
analysed. A set of custom RNA baits designed against 350 full and
partial human adenovirus genomes to capture the full diversity of
the Mastadenoviruses was used to enrich adenoviral DNA during
library preparation (SureSelect target enrichment). DNA extracts
from clinical samples were sequenced on the Illumina MiSeq plat-
form without prior culture or specific PCR amplification. Genome
mapping or de novo assembly were performed using CLC Genomics
Workbench 8.
Results: Genome coverage ranged between 20 and 100%
(median coverage 89%). Nearly-whole genomes were recovered
from 56 out of 96 clinical samples, at mean depths ranging from
7 to >7000× , including one sample with an estimated genome
input of 1200 copies. De novo assembly of cultured isolates pro-
duced consensus sequences identical to the reference sequences for
these strains. We were able to genotype all clinical isolates on the
basis of similarity to reference adenovirus genomes, including sam-
ples for which PCR-based typing had previously failed. No mixed
infections (multiple adenovirus genotypeswithin the same sample)
were identified in this sample cohort. Whole genome sequences
were used to elucidate molecular epidemiology within GOSH.
Conclusions: Using target enrichment we have successfully
performed whole-genome sequencing of adenovirus directly from
clinical samples, avoiding the mutagenic aspects of PCR amplicon-
based sequencing or the loss of diversity associated with culture.
We have genotyped clinical adenovirus samples in a single reaction.
Further sequencing of naso-pharyngeal aspirate and faecal adeno-
virus samples is ongoing. We are using whole-genome sequences
to inform molecular epidemiology and infection control at GOSH.
This work significantly increases the number of adenovirus whole
genome sequences from clinical isolates currently available, which
may aid in future vaccine designs.
Abstract no: 290
Presentation at ESCV 2016: Oral 26
Seroprevalence of hepatitis E virus among the
Portuguese general population and prevalence
of silent infection in blood donors –
HEPeCONTROL
M.S.J. Nascimento ∗ Abreu-Silva eixeira
R.M.S. Oliveira , J.R. Mesquita , J. Tomaz ,
C. Sargento , S. Pereira
1 Laboratório de Microbiologia, Departamento de
Ciências Biológicas, Faculdade de Farmácia da
Universidade do Porto, Porto, Portugal
2 Escola Superior Agrária de Viseu, Instituto
Politécnico de Viseu, Viseu, Portugal
3 Servic¸ o de Sangue e Medicina Transfusional do
Centro Hospitalar Universitário de Coimbra (SSMT
CHUC), Coimbra, Portugal
Introduction: The discovery of autochthonous hepatitis E in
industrialized countries has changed the understanding of hepati-
tis E virus (HEV) infection in these regions, nowknown to bemainly
due to zoonotic transmission of HEV genotype 3 via consumption of
undercooked contaminated porkmeat. Furthermore, the HEV sero-
prevalence that has been described in European countries, as well
as the high rate of asymptomatic HEV infections has led to the con-
cern about transfusion-transmitted HEV infections. Studies carried
out on European blood donors have reported HEV acute infections,
with viraemia (HEV RNA) ranging from 0.08% to 0.14%. In Portugal,
no nationwide survey on HEV seroprevalence has been done, and
the risk of blood donations from HEV silent infected donors has
never been reported.
Aims: The present study aimed to provide detailed information
on the seroprevalence of HEV infection in the Portuguese popula-
tion and evaluate silent HEV infection in Portuguese blood donors.
This study is part of HEPeCONTROL project (60DT2) under EEA
grants funding.
Materials and Methods: Sera from a representative cohort of
the Portuguese population ( n = 1656) distributed by geographic
location (30 territorial units), and age (0–99 years of age) collected
between July 2015 and February 2016 were tested for the presence
of anti-HEV IgG by EIA (recomWell HEV IgG, version 2015, Mikro-
gen). Plasma from blood donors ( n = 2115) of SSMT CHUC collected