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Introduction Serological SARS-CoV-2 assays have an important role in guiding the pandemic response. This research aimed to compare the performance of 2 antinucleocapsid assays. Methods Serum from 49 HCWs was analysed at baseline and 6 months using the Abbott diagnostics SARS-CoV-2 IgG assay and the Roche Diagnostics Elecsys Anti-SARS-CoV-2 total antibody assay. Results At baseline, 14/49 participants (29%) demonstrated antibody reactivity using the Abbott assay. At 6 months, 4/14 participants (29%) continued to demonstrate reactivity. A total of 14/49 (29%) participants had detectable antibodies at baseline using the Roche assay. In total, 13/14 (93%) of participants demonstrated antibody reactivity at 6 months. The Abbott assay showed a statistically significant difference in the signal-to-threshold values of baseline reactive samples when repeated at 6 months (p = 0.001). This was not seen with the Roche assay (p = 0.51). Conclusion In this small study, the Roche Diagnostics Elecsys Anti-SARS-CoV-2 total antibody assay appears superior in performance to the Abbott diagnostics SARS-CoV-2 IgG assay in accurately detecting participants with a history of confirmed COVID-19 disease at 6 months follow-up. This finding should be born in mind in the planning of future seroprevalence studies, especially when considering the use of anti-nucleocapsid assays.

Human herpesvirus 8 (HHV-8) seroprevalence varies geographically and between subpopulations. High seroprevalence rates have been ascribed to men who have sex with men (MSM), African migrants, and HIV-infected individuals. The objective of this study was to determine the seroprevalence of HHV-8 in an Irish population, including specific risk groups. A cross-sectional study of 200 blood donors and 200 genitourinary medicine (GUM) and infectious diseases (ID) clinic patients was performed, with testing for Immunoglobulin G (IgG) antibodies to HHV-8 lytic antigens using a commercial indirect fluorescence assay (Scimedx Corp.). Verification was performed at the Centers for Disease Control and Prevention (CDC). All 200 blood donor samples were negative for HHV-8 IgG antibodies. 21% of GUM and ID patients were positive for HHV-8 IgG antibodies. One hundred of these patients were MSM, 35% of whom were HHV-8 seropositive (46% of HIV-positive MSM and 24% of HIV-negative MSM). Of 100 heterosexual patients, only 7% were HHV-8 seropositive. The absence of seropositivity in 200 Irish blood donors may suggest that Ireland has a low overall population HHV-8 seroprevalence. The proportion of HHV-8 seropositivity in the MSM population was significantly higher than in the heterosexual population and most marked in HIV-positive MSM.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies are an excellent indicator of past COVID-19 infection. As the COVID-19 pandemic progresses, retained sensitivity over time is an important quality in an antibody assay that is to be used for the purpose of population seroprevalence studies. We compared 5,788 health care worker (HCW) serum samples by using two serological assays (Abbott SARS-CoV-2 anti-nucleocapsid immunoglobulin G (IgG) and Roche anti-SARS-CoV-2 anti-nucleocapsid total antibody) and a subset of samples (all Abbott assay positive or grayzone, n = 485) on Wantai SARS-CoV-2 anti-spike antibody enzyme-linked immunosorbent assay (ELISA). For 367 samples from HCW with a previous PCR-confirmed SARS-CoV-2 infection, we correlated the timing of infection with assay results. Overall, seroprevalence was 4.2% on Abbott and 9.5% on Roche. Of those with previously confirmed infection, 41% (150/367) and 95% (348/367) tested positive on Abbott and Roche, respectively. At 21 weeks (150 days) after confirmed infection, positivity on Abbott started to decline. Roche positivity was retained for the entire study period (33 weeks). Factors associated (P ≤ 0.050) with Abbott seronegativity in those with previous PCR-confirmed infection included sex (odds ratio [OR], 0.30 male ; 95% confidence interval [CI], 0.15 to 0.60), symptom severity (OR 0.19 severe symptoms; 95% CI, 0.05 to 0.61), ethnicity (OR, 0.28 Asian ethnicity; 95% CI, 0.12 to 0.60), and time since PCR diagnosis (OR, 2.06 for infection 6 months previously; 95% CI, 1.01 to 4.30). Wantai detected all previously confirmed infections. In our population, Roche detected antibodies up to at least 7 months after natural infection with SARS-CoV-2. This finding indicates that the Roche total antibody assay is better suited than Abbott IgG assay to population-based studies. Wantai demonstrated high sensitivity, but sample selection was biased. The relationship between serological response and functional immunity to SARS-CoV-2 infection needs to be delineated. IMPORTANCE As the COVID-19 pandemic progresses, retained sensitivity over time is an important quality in an antibody assay that is to be used for the purpose of population seroprevalence studies. There is a relative paucity of published literature in this field to help guide public health specialists when planning seroprevalence studies. In this study, we compared results of 5,788 health care worker blood samples tested by using two assays (Roche and Elecsys, anti-nucleocapsid antibody) and by testing a subset on a third assay (Wantai enzyme-linked immunosorbent assay [ELISA] anti-spike antibody). We found significant differences in the performance of these assays, especially with distance in time from PCR-confirmed COVID-19 infection, and we feel these results may significantly impact the choice of assay for others conducting similar studies.

SARS-CoV-2 antibodies are an excellent indicator of past COVID-19 infection. As the COVID-19 pandemic progresses, retained sensitivity over time is an important quality in an antibody assay that is to be used for the purpose of population seroprevalence studies.We compared 5788 healthcare worker (HCW) serum samples on two serological assays (Abbott SARS-CoV-2 anti-nucleocapsid IgG and Roche Anti-SARS-CoV-2 anti-nucleocapsid Total Antibody) and a subset of samples (all Abbott assay positive or grayzone, n=485) on Wantai SARS-CoV-2 anti-spike Antibody ELISA. For 367 samples from HCW with previous PCR-confirmed SARS-CoV-2 infection we correlated the timing of infection with assay results.Overall seroprevalence was 4.2% on Abbott, 9.5% on Roche. Of those with previously confirmed infection, 41% (150/367) and 95% (348/367) tested positive on Abbott and Roche respectively. At 21 weeks (150 days) after confirmed infection, positivity on Abbott started to decline. Roche positivity was retained for the entire study period (33 weeks). Factors associated (P≤ 0.050) with Abbott seronegativity in those with previous PCR-confirmed infection included sex (male OR0.30;95%CI0.15-0.60), symptom severity (OR0.19 severe symptoms;95%CI0.05-0.61), ethnicity (OR0.28 Asian ethnicity;95%CI0.12-0.60) and time since PCR diagnosis (OR2.06 for infection 6 months previously;95%CI1.01-4.30. Wantai detected all previously confirmed infections.In our population, Roche detected antibodies up to at least seven months after natural infection with SARS-CoV-2. This may indicate that Roche is better suited than Abbott to population-based studies. Wantai demonstrated high sensitivity but sample selection was biased. The relationship between serological response and functional immunity to SARS-CoV-2 infection needs to be delineated.

BackgroundWe initiated an emergency department (ED) opt-out screening programme for HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) at our hospital in Dublin, Ireland. The objective of this study was to determine screening acceptance, yield and the impact on follow-up care.MethodsFrom July 2015 through June 2018, ED patients who underwent phlebotomy and could consent to testing were tested for HIV, HBV and HCV using an opt-out approach. We examined acceptance of screening, linkage to care, treatment and viral suppression using screening programme data and electronic health records. The duration of follow-up ranged from 1 to 36 months.ResultsOver the 36-month study period, there were 140 550 ED patient visits, of whom 88 854 (63.2%, 95% CI 63.0% to 63.5%) underwent phlebotomy and 54 817 (61.7%, 95% CI 61.4% to 62.0%) accepted screening for HIV, HBV and HCV, representing 41 535 individual patients. 2202 of these patients had a positive test result. Of these, 267 (12.1%, 95% CI 10.8% to 13.6%) were newly diagnosed with an infection and 1762 (80.0%, 95% CI 78.3% to 81.7%) had known diagnoses. There were 38 new HIV, 47 new HBV and 182 new HCV diagnoses. 81.5% (95% CI 74.9% to 87.0%) of known patients who were not linked were relinked to care after screening. Of the new diagnoses, 86.2% (95% CI 80.4 to 90.8%) were linked to care.ConclusionAlthough high proportions of patients had known diagnoses, our programme was able to identify many new infected patients and link them to care, as well as relink patients with known diagnoses who had been lost to follow-up.

The standard of care for fit patients with Mantle Cell Lymphoma (MCL) includes cytarabine containing induction treatment and consolidation with BEAM (Carmustine, Etoposide, Cytarabine and Melphalan). Chemo-refractory cases have a poorer prognosis and are candidates for allogenic stem cell transplantation (allo-SCT). Targeted therapy, such as BTK-inhibitors or BCL-mimetics can be used to bridge patients to SCT. COVID-19, a novel coronavirus has the potential to cause life threatening immune dysregulation and cytokine release syndrome (CRS) resulting in respiratory failure. Haematology patients, particularly post allogenic stem cell transplant, are high risk for developing CRS due to T-lymphopenia. PD, a 55-year-old male, with chemo-refractory MCL tested positive for COVID-19 day + 45 post allo-SCT after presenting with mild gastrointestinal symptoms and remained positive for 70 days. At day + 92 relapse was confirmed by CT and axillary node biopsy. Ibrutinib, a BTK inhibitor, was commenced with resolution of symptoms and a negative test within 20 days. With minimal reduction in adenopathy, Ibrutinib was stopped at day +110, while Cytarabine and Venetoclax (BCL-mimetic) were commenced with Donor lymphocyte infusion at day +145 resulting in complete remission. Ibrutinib’s therapeutic role against COVID-19 is now being investigated in clinical trials.

The Hepatitis B vaccine is highly effective for the prevention of hepatitis B (HBV) infection. We report the development of chronic HBV infection (Genotype F) in a vaccinated immunocompetent individual with an anti-HBsAb of 35 mIU/mL post completion of vaccine series. HBV vaccine is based on recombinant proteins of genotype-A and D (predominant genotypes in Europe). It may not be as effective for the prevention of more genetically diverse viruses such as genotype F (predominant genotype in Central and South America). Healthcare providers and patients should be aware that the HB vaccine does not confer 100% protection against HBV infection, even in the setting of protective antibody levels. Partners of individuals infected with non-A or -D genotypes should be advised to consider additional precautions to prevent transmission even in the setting protective antibody levels. Surveillance of circulating HBV genotypes should be undertaken to inform public health policy in relation to prevention of HB in high-risk groups such as men who have sex with men.

Central venous catheter (CVC) tip cultures are useful in the assessment of a patient with a potential catheter-related bloodstream infection (CRBSI). However, these results can be misleading particularly in the absence of concomitant peripheral and central line blood cultures. Catheter tip cultures should not be submitted to the laboratory unless CRBSI is suspected as the predictive value of culture results depends on the pretest probability of CRBSI. A positive CVC tip culture does not usually warrant further investigation or therapy (except in the case of Staphylococcus aureus and possibly Candida sp) while a negative catheter tip culture in isolation does not definitively exclude CRBSI. Clinicians can use alternative criteria for the diagnosis of CRBSI that do not require catheter tip cultures if necessary. Further research into the significance of CVC tip cultures in the absence of concomitant bacteraemia is required.

Objectives Studies suggest 2 per 1000 people in Dublin are living with HIV, the level above which universal screening is advised. We aimed to assess the feasibility and acceptability of a universal opt-out HIV, Hepatitis B and Hepatitis C testing programme for Emergency Department patients and to describe the incidence and prevalence of blood-borne viruses in this population. Methods An opt-out ED blood borne virus screening programme was piloted from March 2014 to January 2015. Patients undergoing blood sampling during routine clinical care were offered HIV 1&2 antibody/antigen assay, HBV surface antigen and HCV antibody tests. Linkage to care where necessary was co-ordinated by the study team. New diagnosis and prevalence rates were defined as the new cases per 1000 tested and number of positive tests per 1000 tested respectively. Results Over 45 weeks of testing, of 10,000 patient visits, 8,839 individual patient samples were available for analysis following removal of duplicates. A sustained target uptake of >50% was obtained after week 3.97(1.09%), 44(0.49%) and 447(5.05%) HIV, Hepatitis B and Hepatitis C tests were positive respectively. Of these, 7(0.08%), 20(0.22%) and 58(0.66%) were new diagnoses of HIV, Hepatitis B and Hepatitis C respectively. The new diagnosis rate for HIV, Hepatitis B and Hepatitis C was 0.8, 2.26 and 6.5 per 1000 and study prevalence for HIV, Hepatitis B and Hepatitis C was 11.0, 5.0 and 50.5 per 1000 respectively. Conclusions Opt-out blood borne viral screening was feasible and acceptable in an inner-city ED. Blood borne viral infections were prevalent in this population and newly diagnosed cases were diagnosed and linked to care. These results suggest widespread blood borne viral testing in differing clinical locations with differing population demographic risks may be warranted.

The Small Negative Ion Facility (SNIF) at CCFE has been undergoing continuous development and enhancement to both improve operational reliability and increase diagnostic capability. SNIF uses a CW 13.56MHz, 5kW RF driven volume source with a 30kV triode accelerator. Improvement and characterisation work includes: Installation of a new “L” type RF matching unit, used to calculate the load on the RF generator. Use of the electron suppressing biased insert as a Langmuir probe under different beam extraction conditions. Measurement of the hydrogen Fulcher molecular spectrum, used to calculate gas temperature in the source. Beam optimisation through parameter scans, using copper target plate and visible cameras, with results compared with AXCEL-INP to provide beam current estimate. Modelling of the beam power density profile on the target plate using ANSYS to estimate beam power and provide another estimate of beam current. This work is described, and has allowed an estimation of the extracted beam current of approximately 6mA (4mA/cm2) at 3.5kW RF power and a source pressure of 0.6Pa.

A Fast Ion Deuterium Alpha (FIDA) spectrometer was installed on MAST to measure radially resolved information about the fast ion density and its distribution in energy and pitch angle. Toroidally and vertically-directed collection lenses are employed, to detect both passing and trapped particle dynamics, and reference views are installed to subtract the background. This background is found to contain a substantial amount of passive FIDA emission driven by edge neutrals, and to depend delicately on viewing geometry. Results are compared with theoretical expectations based on the codes NUBEAM (for fast ion distributions) and FIDASIM. Calibrating via the measured beam emission peaks, the toroidal FIDA signal profile agrees with classical simulations in MHD quiescent discharges where the neutron rate is also classical. Long-lived modes (LLM) and chirping modes decrease the core FIDA signal significantly, and the profile can be matched closely to simulations using anomalous diffusive transport; a spatially uniform diffusion coefficient is sufficient for chirping modes, while a core localized diffusion is better for a LLM. Analysis of a discharge with chirping mode activity shows a dramatic drop in the core FIDA signal and rapid increase in the edge passive signal at the onset of the burst indicating a very rapid redistribution towards the edge. Vertical viewing measurements show a discrepancy with simulations at higher Doppler shifts when the neutron rate is classical, which, combined with the fact that the toroidal signals agree, means that the difference must be occurring for pitch angles near the trapped-passing boundary. Further evidence of an anomalous transport mechanism for these particles is provided by the fact that an increase of beam power does not increase the higher energy vertical FIDA signals, while the toroidal signals do increase., submitted to PPCF

Primary cytomegalovirus (CMV) infection with marked constitutional symptoms is rare in immunocompetent individuals and in those with iatrogenic immunosuppression, except transplant recipients. Four patients admitted to hospital with clinical illnesses associated with primary CMV infection were identified over a 12-month period. Their medical records were reviewed with regard to clinical and laboratory data, and outcome. Primary CMV infection was defined by the concomitant presence of CMV IgM and low avidity CMV IgG antibody. Of two patients with no known underlying illness, one presented with thrombocytopenic purpura and the other with vasculitis. Two patients receiving immunosuppressants for underlying ulcerative colitis presented with CMV-induced pancytopenia and CMV colitis. Atypical lymphocytosis was a feature on blood film examination in three of the four cases. One patient with disseminated CMV infection died of progressive multiorgan failure despite antiviral treatment. CMV disease following primary CMV infection should be considered in otherwise immunocompetent individuals with atypical lymphocytosis on blood film analysis, and particularly in patients on immunosuppressants such as those with ulcerative colitis, since early diagnosis and treatment with antiviral drugs may improve outcome. J. Med. Virol. 68: 237–240, 2002. © 2002 Wiley-Liss, Inc.

Measurements have been made of the emittance plot of a partly neutralized positive ion beamlet, using a slit, a polymer target, and an infrared camera. This thermographic approach is intrinsically linear and absolute (since the properties of the target are known and approximately independent of temperature). It is sufficiently sensitive that only one short pulse is required to capture the entire range of the angular coordinate y('). Ions and neutral atoms are both detected with equal sensitivity. The measurement is unaffected by secondary electrons emitted by the target and by electrons traveling with the positive ion beam, as both types of electron carry very little energy. No specialized electronics or beam deflection devices are required. Providing the region downstream of the mask is free of fields, the target can be several meters away from the mask, allowing good resolution in the y(') axis. The target can be as large as required.