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

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S30 Abstracts / Journal of Clinical Virology 82S (2016) S1–S142
positive, 2 equivocal and 5 negative. The two CSF-samples with
equivocal result and three of the negative CSF samples had cor-
responding serum samples that were positive for TBE IgM using
Reascan.
Conclusions: According to this small evaluation the ReaS-
can IgM rapid test seems to have a comparable performance
to two commercially available ELISA assays (Euroimmun and
Immunozym) for the detection of TBE IgM in serum. The two sam-
ples with equivocal Reascan-result originated from one patient on
immunosuppression and one who acquired TBE despite vaccina-
tion. As others have shown the additive value of testing for IgM in
CSF might be limited as only two out of nine samples here tested
were positive. The Reascan TBE IgM assay seems as a valid diag-
nostic option for a rapid diagnosis of TBE. Additional ELISA with
analysis of both IgM and IgG as well as molecular detection of TBE
might be performed as confirmatory tests.
Abstract no: 158
Presentation at ESCV 2016: Poster 18
Comparison of in-house TaqMan assay versus
the Luminex Multicode technology on the ARIES
platform for detection of Influenza A/B and RSV
A/B
Colleen Smedley ∗, Mehmet Yavuz,
Duncan Whittaker
Sheffield Teaching Hospitals, United Kingdom
Influenza and respiratory syncytial virus (RSV) infections are
reported to cause 80–90% of viral lower respiratory tract infections
being responsible for significant morbidity and mortality world-
wide. It is estimated that RSV affects virtually all children by their
2nd birthday, and is the most important cause of infant lower
respiratory tract infections, causing an estimated 70% of paedi-
atric hospitalisations due to bronchiolitis. Patients with underlying
health conditions are at particular risk of complicated infection
with both Influenza and RSV,with the elderly and those immuno-
suppressed due to cancer therapies such as haematopoietic stem
cell transplant (HSCT) at particular risk.
Influenza diagnosis based on clinical findings and suspicion
alone has been shown to be lacking in sensitivity and specificity.
Clinical differentiation between RSV and Influenza infections can be
challenging due to their similar clinical presentations and as such
diagnosis of infections is largely laboratory based, with timely and
accurate diagnosis a cornerstone of patient management and infec-
tion control. Molecular methods have superseded conventional cell
culture however their batched nature makes them inefficient for
urgent testing. TaqMan PCR, though sensitive and specific, is batch
tested, with time to result exceeding 3 h for urgent specimens.
The goal of this study was to evaluate the performance of the
ResearchUseOnly (RUO) Influenza andRSV assaymade available by
Luminex, alongside a novel, multicode based laboratory developed
test (LDT) for Influenza A/B and RSV. The LDT assay adapted the
routinely used TaqMan primers for use on the ARIES through mod-
ification to include IsoC at the 5 end of the forward primer. Both
the RUO and LDT methods were compared to the routinely used
TaqMan PCR assay. This study also aimed to determine whether
the ARIES platform and assay technology is a suitable diagnos-
tic tool for Influenza and RSV detection in patient groups where
urgent results with a highly sensitive and specific methodology are
required. This is the first study to describe development of an LDT
assay for Influenza/RSV on the ARIES platform.
Between January and March 2016, 219 prospective and retro-
spective mixed respiratory specimens were tested by TaqMan PCR
and LDT assay, with 114 of these also tested with the RUO method.
The RUO and LDT assays proved to be as sensitive and specific as
TaqMan PCR, withmuchdecreased operator time and time to result.
The LDT assay was also able to differentiate between RSV A and RSV
B. The ARIES instrument provided a simplemethod bywhich urgent
specimens could be tested, with potential to allow testing 24 h per
day by suitably trained staff.
Abstract no: 162
Presentation at ESCV 2016: Poster 19
Antibody detection and qPCR assay for an
accurate diagnosis of parvovirus B19 infection
E. Manaresi ∗, I. Conti, G. Bua, F. Bonvicini,
G. Gallinella
University of Bologna, Italy
B19V is a virus capable of infections presenting with differ-
ent courses depending on the interplay with host factors and
the efficacy of the immune system response. An accurate lab-
oratory diagnosis of B19V infection can take advantage of a
multi-parametric approach, combining as far as possible the
immunological detection of virus-specific antibodies to the molec-
ular detection of viral components, mainly viral DNA
In the period September 2014–December 2015, a total of 3128
serum samples were analysed for the detection of B19V specific
antibodies by a VLP-based CLIA assay (DiaSorin, Italy). Of these,
293 were also investigated by qPCR for the detection of B19V DNA
and determination of the viral load (Bonvicini, 2013).
Results for antibody detection indicated, when considering a
cut-off value (COV) of 1.0, 57.8% of samples positive for IgG and
11.4% for IgM(7.6% double positive); when considering a COV of 3.0,
51.7% of samples positive for IgG and 4.2% for IgM (3.1% double pos-
itive). qPCR detection of B19V DNA was employed to discriminate
active infection and disease condition in a ROC analysis for IgM val-
ues. At IgMCOV = 1.0, sensitivitywas 0.67 and specificity 0.88, while
at IgM COV = 3.0, sensitivity was 0.54 and specificity was 0.98. The
low sensitivity values could be attributed to the presence of about
16–17% of PCR positive samples in the IgG positive/IgM negative
sample set, indicative of persistent infections. On the other hand,
the observed change in specificity in dependence of the COV was
due to a more accurate discrimination of the PCR positive samples
within the IgM positive sample set, from 17 to 80%.
The immunological approach to the diagnosis of B19V infection
is regularly followed as a first level investigation. However, due
to the characteristics of B19V infectious course and the observed
difficulty in obtaining an optimal cut-off level for IgM reactivity,
there remains a strong indication for molecular testing aimed to
the confirmation of suspected active infections, the discrimination
of persistent infections, and the follow-up of the course of docu-
mented infections.