Annual Conference 2018
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Annual Conference 2018 POSTER ABSTRACT BOOK 10–13 April, ICC Birmingham, UK @MicrobioSoc #Microbio18 Virology Workshop: Clinical Virology Zone A Presentations: Wednesday and Thursday evening P001 Rare and Imported Pathogens Lab (RIPL) turn around time (TAT) for the telephoned communication of positive Zika virus (ZIKV) PCR and serology results. Zaneeta Dhesi, Emma Aarons Rare and Imported Pathogens Lab, Public Health England, Salisbury, United Kingdom Abstract Background: RIPL introduced developmental assays for ZIKV PCR and serology on 18/01/16 and 10/03/16 respectively. The published ZIKV test TATs were 5 days for PCR and 7 days for serology. Methods: All ZIKV RNA positive, seroconversion and “probable” cases diagnosed at RIPL up until 31/05/17 were identified. For each case, the date on which the relevant positive sample was received, and the date on which it was telephoned out to the requestor was ascertained. The number of working days between these two dates was calculated. Results: ZIKV PCR - 151 ZIKV PCR positive results were identified, of which 4 samples were excluded because no TAT could be calculated. The mean TAT for the remaining 147 samples was 1.7 working days. Ninety percent of these results were telephoned within 3 or fewer days of the sample having been received. There was 1 sample where the TAT was above the 90th centile. ZIKV Serology - 147 seroconversion or “Probable” ZIKV cases diagnosed serologically were identified. The mean TAT for these samples was 2.5 working days. Ninety percent of these results were telephoned within 4 or fewer days of the sample having been received. There were 6 samples where the TAT was more than 4 days. Conclusion: The TAT for telephoning of positive ZIKV test results has been satisfactory whilst RIPL has had a “Zika registrar”. A smaller scale audit of telephoning of positive ZIKV results should be performed in rotation with other similar audits (ie for leptospirosis, dengue, chikungunya etc). Virology Workshop: Clinical Virology Zone A Presentations: Wednesday and Thursday evening P002 The development of a genotypic assay detecting drug-resistance mutations in herpes simplex virus type 2. Fangyue Chen, Jane Greatorex University of Cambridge, Cambridge, United Kingdom Abstract Background: the emerging herpes simplex virus type 2 antiviral resistance has been of major concern. Genotypic assay involving the identification of resistance-associated mutations in HSV-2 thymidine kinase (tk) and/or DNA polymerase (pol) is more rapid and less labour-intensive than the current gold standard plaque reduction assay. In this project, a robust genotypic assay using the Next Generation Sequencing technology is in development. Method: for the sequencing assay PCR amplifying HSV-2 pol and tk genes, PCR conditions were optimised, focusing on MgCl2, DMSO concentrations, and annealing temperature. The sensitivity and specificity of the nested PCR for HSV-2 tk and pol were determined. Finally, a comprehensive search of the existing literature was performed and a HSV-2 tk and pol drug-resistance mutation database was constructed. Each mutation was linked to a specific drug susceptibility profile. Results: after optimising the nested PCR sequencing assays for HSV-2 tk and pol genes, the sensitivity of the assays was determined: for tk, the limits of detection was at a viral load of 1000-5000 copies/ml; for pol, >=3000 copies/ml. The assays were found to be highly specific. The drug-resistance mutation database was constructed containing 57 mutations for tk, 19 mutations for pol. Conclusion: a genotypic assay testing for resistance-associated mutations in HSV-2 is in development. Further work will include the testing of clinical samples, notably those with drug-resistance mutations as tested phenotypically. Based on the database, an automated, searchable tool is currently in development for clinical report generation. Virology Workshop: Clinical Virology Zone A Presentations: Wednesday and Thursday evening P003 Prevalence of baseline NS5A resistance in patients infected with genotype 1A hepatitis C virus in Scotland. Amanda Bradley-Stewart, Emily Goldstein, Alasdair MacLean, Rory Gunson West of Scotland Specialist Virology Centre, Glasgow, United Kingdom Abstract Background Current treatment for hepatitis C virus includes direct-acting antivirals (DAAs). EASL guidelines recommend testing for resistance to NS5A inhibitors prior to treatment in patients infected with genotype 1A (G1A) virus, as resistance-associated amino acid substitutions (RAS) can exist at baseline in treatment naïve individuals, and have been shown to be associated with lower rates of sustained virological response (SVR). Methods The aim of the study was to measure the prevalence of baseline NS5A resistance in Scotland. The study population consisted of 525 treatment naïve, G1A infected patients. The patient samples were collected between March and September 2017. The NS5A region was amplified and sequenced using Sanger sequencing and nine amino acid positions associated with resistance were examined. Results Eighty-eight patients (16.8%) had NS5A inhibitor resistance at baseline. Seventy-two patients had single mutations, 15 patients had dual mutations and one patient had a triple mutation. These results are comparable to rates reported in a number of previously published studies. Conclusion The high rate of baseline RAS in Scotland, together with the high cost of DAAs, supports resistance testing in G1A infected patients prior to treatment. However, given the rate at which new DAAs are currently being licensed, with ever broader genotype efficacy and higher SVR rates, baseline resistance testing may not be required in the near future. Virology Workshop: Clinical Virology Zone A Presentations: Wednesday and Thursday evening P004 Clinical outcomes of Hepatitis E in a large district general hospital - a 3 year retrospective analysis Thomas Lamb1,2, Joel Paul1 1Pennine Acute Trust, Oldham, United Kingdom. 2University of Edinburgh, Edinburgh, United Kingdom Abstract Hepatitis E is a single stranded RNA virus first recognised in India in 1978. Differing from endemic countries where contaminated drinking water can result in large epidemics, UK acquired infection is a most commonly zoonotic transmission resulting in small clusters and sporadic cases. In the UK, Hepatitis E is an emerging disease with case numbers increasing from 124 cases in 2003 to 891 in 2016. Given its increasing disease burden, further clinical information is required particularly related to the dominating UK genotypes, 3 and 4. We conducted a retrospective analysis of cases tested for Hepatitis E from Pennine Acute Trust, a large district general hospital over a three-year period to November 2017. A total of 900 serum samples were referred to the reference laboratory. We present the clinical outcome of these patients, the recognised risk factors including alcohol consumption and co-morbidities and their correlation with disease severity. A trend of increased sampling correlates with a rise in case numbers confirmed by Public Health England. Virology Workshop: Clinical Virology Zone A Presentations: Wednesday and Thursday evening P005 Cytomegalovirus and varicella-zoster virus infections in a cohort of multiple sclerosis patients assessed over a period of one year Peter Maple, Radu Tanasescu, Cris Constantinescu University of Nottingham, Nottingham, United Kingdom Abstract Background. In the UK multiple sclerosis (MS) is the leading cause of disability in young adults. Most cases of MS initially present with relapsing and remitting episodes (RRMS) which, over time, are superseded by progressive disease. RRMS is characterized by episodes of demyelination as a consequence of autoimmune mechanisms linked to T and B cell dysregulation. Cytomegalovirus (CMV) and varicella-zoster virus (VZV) establish latency following primary infection and reactivation is associated with failing cell-mediated immunity. Methods. Serum samples collected at various time points over one year were available from a cohort of 51 predominantly RRMS patients. The cohort had regular physical examinations and magnetic resonance imaging conducted over the study period. CMV and VZV-IgG levels were measured by enzyme-linked immunosorbent assay. Results. At the beginning of the study, 17 patients were CMV-IgG positive (geometric mean CMV IgG = 324 PEI units/ml). CMV IgG levels remained stable (at 12 months geometric mean CMV-IgG = 365 PEI units/ml) and there were no new seroconversions. For VZV, all patients were VZV-IgG positive and geometric mean VZV-IgG levels at 0 months and 12 months of 1367 mIU/ml and 1342 mIU/ml, respectively were measured. One patient was diagnosed with zoster sine herpete. A total of 14 patients had clinical relapses during the period of the study; however, none of these were associated with serological evidence of VZV reactivation. Conclusion. CMV and VZV infection in RRMS patients has been studied and no evidence of an association with clinical relapse was found. Virology Workshop: Clinical Virology Zone A Presentations: Wednesday and Thursday evening P006 Assessing the potential of a portable DNA sequencer, MinION, as a front line tool to detect and characterise notifiable and emerging animal viral disease. Charlotte Bickers Royal Veterinary College, London, United Kingdom. Animal Plant Health Agency, Weybridge, United Kingdom Abstract In 2015, Oxford nanopore technologies commercialised a portable DNA sequencer known as minION. In recent years, there has been an