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The emergence and attendant mortality of vaccine-induced immune thrombocytopenia and thrombosis (VITT) as a consequence of vaccination against severe acute respiratory syndrome coronavirus 2 have resulted in some patients with VITT being considered as deceased organ donors. Outcomes after kidney transplantation in this context are poorly described. Because the disease seems to be mediated by antiplatelet factor 4 antibodies, there is a theoretical risk of transmission via passenger leukocytes within the allograft.We analyzed the experience of kidney transplantation from donors with VITT in the United Kingdom between January and June 2021. We followed-up all recipients of kidney-only transplants from donors with VITT to detect major postoperative complications or features of disease transmission and assess graft survival and function.There were 16 kidney donors and 30 single kidney transplant recipients in our study period. Of 11 preimplantation biopsies, 4 showed widespread glomerular microthrombi. After a median of 5 mo, patient and graft survival were 97% and 90%, respectively. The median 3-mo estimated glomerular filtration rate was 51 mL/min/1.73 m 2 . Two recipients had detectable antiplatelet factor 4 antibodies but no evidence of clinical disease after transplantation. Major hemorrhagic complications occurred in 3 recipients, all of whom had independent risk factors for bleeding, resulting in the loss of 2 grafts. The involvement of VITT could not be completely excluded in one of these cases.The UK experience to date shows that favorable outcomes are possible after kidney transplantation from donors with VITT but highlights the need for ongoing vigilance for donor-related complications in these patients.

The clinical effectiveness of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in immunosuppressed solid organ and islet transplant (SOT) recipients is unclear.We linked 4 national registries to retrospectively identify laboratory-confirmed SARS-CoV-2 infections and deaths within 28 d in England between September 1, 2020, and August 31, 2021, comparing unvaccinated adult SOT recipients and those who had received 2 doses of ChAdOx1-S or BNT162b2 vaccine. Infection incidence rate ratios were adjusted for recipient demographics and calendar month using a negative binomial regression model, with 95% confidence intervals. Case fatality rate ratios were adjusted using a Cox proportional hazards model to generate hazard ratio (95% confidence interval).On August 31, 2021, it was found that 3080 (7.1%) were unvaccinated, 1141 (2.6%) had 1 vaccine dose, and 39 260 (90.3%) had 2 vaccine doses. There were 4147 SARS-CoV-2 infections and 407 deaths (unadjusted case fatality rate 9.8%). The risk-adjusted infection incidence rate ratio was 1.29 (1.03-1.61), implying that vaccination was not associated with reduction in risk of testing positive for SARS-CoV-2 RNA. Overall, the hazard ratio for death within 28 d of SARS-CoV-2 infection was 0.80 (0.63-1.00), a 20% reduction in risk of death in vaccinated patients (P = 0.05). Two doses of ChAdOx1-S were associated with a significantly reduced risk of death (hazard ratio, 0.69; 0.52-0.92), whereas vaccination with BNT162b2 was not (0.97; 0.71-1.31).Vaccination of SOT recipients confers some protection against SARS-CoV-2-related mortality, but this protection is inferior to that achieved in the general population. SOT recipients require additional protective measures, including further vaccine doses, antiviral drugs, and nonpharmaceutical interventions.

Vaccine-induced immune thrombosis and thrombocytopenia (VITT) syndrome is a new entity, characterised by severe thrombocytopenia and multiple sites of thrombosis1 . The presumed mechanism is driven by anti-platelet factor 4 (PF4) antibodies causing platelet activation1 . Donors with VITT syndrome have a particular relevance for liver transplantation (LT), due to the associated risk of passenger lymphocyte syndrome, and a predisposition for porto-mesenteric or hepatic vein thrombosis2 .

Since the first reports of hepatitis of unknown aetiology occurring in UK children, over 1000 cases have been reported worldwide, including 268 cases in the UK, with the majority younger than 6 years old. Using genomic, proteomic and immunohistochemical methods, we undertook extensive investigation of 28 cases and 136 control subjects. In five cases who underwent liver transplantation, we detected high levels of adeno-associated virus 2 (AAV2) in the explanted livers. AAV2 was also detected at high levels in blood from 10/11 non-transplanted cases. Low levels of Adenovirus (HAdV) and Human Herpesvirus 6B (HHV-6B), both of which enable AAV2 lytic replication, were also found in the five explanted livers and blood from 15/17 and 6/9 respectively, of the 23 non-transplant cases tested. In contrast, AAV2 was detected at low titre in 6/100 whole bloods from child controls from cohorts with presence or absence of hepatitis and/or adenovirus infection. Our data show an association of AAV2 at high titre in blood or liver tissue, with unexplained hepatitis in children infected in the recent HAdV-F41 outbreak. We were unable to find evidence by electron microscopy, immunohistochemistry or proteomics of HAdV or AAV2 viral particles or proteins in explanted livers, suggesting that hepatic pathology is not due to direct lytic infection by either virus. The potential that AAV2, although not previously associated with disease, may, together with HAdV-F41 and/or HHV-6, be causally implicated in the outbreak of unexplained hepatitis, requires further investigation.

Vaccine-induced thrombosis and thrombocytopenia (VITT) may follow immunisation with the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2. Autoantibodies to platelet factor 4 (PF4) may mediate VITT through antibody-dependent platelet activation, though the underlying etiology is uncertain. Anti-PF4 antibodies are also seen in heparin-induced thrombocytopenia, though most cases of VITT do not have prior heparin exposure. More than 20 million people in the United Kingdom (UK) have received the ChAdOx1 nCoV-19 vaccine.

Patients who undergo solid organ transplantation are at risk of opportunistic infection associated with immunosuppression. We report a case of confirmed donor derived visceral leishmaniasis (VL), in a patient following liver transplantation causing fever and pancytopenia. The diagnosis was confirmed by bone marrow biopsy, with confirmed positive donor serology, with no other route of transmission. To our knowledge, this is the first case report in the United Kingdom and Europe, of confirmed organ donor transmission of VL. This case report highlights an important consideration of donor derived infections, in the context of solid organ transplantation.

We describe a case of proven transmission of SARS‐CoV‐2 from lung donor to recipient. The donor had no clinical history or findings suggestive of infection with SARS‐CoV‐2 and tested negative by reverse transcriptase polymerase chain reaction (RT‐PCR) on a nasopharyngeal (NP) swab obtained within 48 h of procurement. Lower respiratory tract testing was not performed. The recipient developed fever, hypotension, and pulmonary infiltrates on posttransplant day (PTD) 3, and RT‐PCR testing for SARS‐CoV‐2 on an NP swab specimen was non‐reactive, but positive on bronchoalveolar lavage (BAL) fluid. One thoracic surgeon present during the transplantation procedure developed COVID‐19. Sequence analysis of isolates from donor BAL fluid (obtained at procurement), the recipient, and the infected thoracic surgeon proved donor origin of recipient and health‐care worker (HCW) infection. No other organs were procured from this donor. Transplant centers and organ procurement organizations should perform SARS‐CoV‐2 testing of lower respiratory tract specimens from potential lung donors, and consider enhanced personal protective equipment for HCWs involved in lung procurement and transplantation.

SARS-CoV-2 Spike protein is critical for virus infection via engagement of ACE2, and amino acid variation in Spike is increasingly appreciated. Given both vaccines and therapeutics are designed around Wuhan-1 Spike, this raises the theoretical possibility of virus escape, particularly in immunocompromised individuals where prolonged viral replication occurs. Here we report chronic SARS-CoV-2 with reduced sensitivity to neutralising antibodies in an immune suppressed individual treated with convalescent plasma, generating whole genome ultradeep sequences by both short and long read technologies over 23 time points spanning 101 days. Although little change was observed in the overall viral population structure following two courses of remdesivir over the first 57 days, N501Y in Spike was transiently detected at day 55 and V157L in RdRp emerged. However, following convalescent plasma we observed large, dynamic virus population shifts, with the emergence of a dominant viral strain bearing D796H in S2 and ΔH69/ΔV70 in the S1 N-terminal domain NTD of the Spike protein. As passively transferred serum antibodies diminished, viruses with the escape genotype diminished in frequency, before returning during a final, unsuccessful course of convalescent plasma. In vitro, the Spike escape double mutant bearing ΔH69/ΔV70 and D796H conferred decreased sensitivity to convalescent plasma, whilst maintaining infectivity similar to wild type. D796H appeared to be the main contributor to decreased susceptibility, but incurred an infectivity defect. The ΔH69/ΔV70 single mutant had two-fold higher infectivity compared to wild type and appeared to compensate for the reduced infectivity of D796H. Consistent with the observed mutations being outside the RBD, monoclonal antibodies targeting the RBD were not impacted by either or both mutations, but a non RBD binding monoclonal antibody was less potent against ΔH69/ΔV70 and the double mutant. These data reveal strong selection on SARS-CoV-2 during convalescent plasma therapy associated with emergence of viral variants with reduced susceptibility to neutralising antibodies.

Patients waitlisted for and recipients of solid organ transplants (SOT) are perceived to have a higher risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and death; however, definitive epidemiological evidence is lacking. In a comprehensive national cohort study enabled by linkage of the UK transplant registry and Public Health England and NHS Digital Tracing services, we examined the incidence of laboratory-confirmed SARS-CoV-2 infection and subsequent mortality in patients on the active waiting list for a deceased donor SOT and recipients with a functioning SOT as of February 1, 2020 with follow-up to May 20, 2020. Univariate and multivariable techniques were used to compare differences between groups and to control for case-mix. One hundred ninety-seven (3.8%) of the 5184 waitlisted patients and 597 (1.3%) of the 46 789 SOT recipients tested positive for SARS-CoV-2. Mortality after testing positive for SARS-CoV-2 was 10.2% (20/197) for waitlisted patients and 25.8% (154/597) for SOT recipients. Increasing recipient age was the only variable independently associated with death after positive SARS-CoV-2 test. Of the 1004 transplants performed in 2020, 41 (4.1%) recipients have tested positive for SARS-CoV-2 with 8 (0.8%) deaths reported by May 20. These data provide evidence to support decisions on the risks and benefits of SOT during the coronavirus disease 2019 pandemic.

Deceased organ donors are routinely screened for behaviors that increase the risk of transmissible blood-borne viral (BBV) infection, but the impact of this information on organ donation and transplant outcome is not well documented. Our aim was to establish the impact of such behavior on organ donation and utilization, as well transplant recipient outcomes.We identified all UK deceased organ donors from 2003 to 2015 with a disclosed history of increased risk behavior (IRB) including intravenous drug use (IVDU), imprisonment and increased risk sexual behavior.Of 17 262 potential donors, 659 (3.8%) had IRB for BBV and 285 (1.7%) were seropositive for BBV, of whom half had a history of IRB (mostly IVDU [78.5%]). Of actual donors with IRB, 393 were seronegative for viral markers at time of donation. A history of recent IVDU was associated with fewer potential donors proceeding to become actual organ donors (64% vs 75%, P = 0.007). Donors with IRB provided 1091 organs for transplantation (624 kidneys and 467 other organs). Transplant outcome was similar in recipients of organs from donors with and without IRB. There were 3 cases of unexpected hepatitis C virus transmission, all from an active IVDU donor who was hepatitis C virus seronegative at time of donation, but was found to be viremic on retrospective testing.Donors with a history of IRB provide a valuable source of organs for transplantation with good transplant outcomes and there is scope for increasing the use of organs from such donors.

The accurate diagnosis and seroprevalence investigations of Zika virus (ZKV) infections remain complex due to cross reactivity with other flaviviruses. Two assay formats, both using labelled Zika virus NS1 antigen as a revealing agent (a double antigen binding assay, DABA, and an immunoglobulin Ig capture assay, IgG capture) were initially developed and compared with the indirect EuroimmunZ assay for the detection of anti-Zika antibody. Of 147 pre-Zika period serum samples, 39 (27%) were reactive in the EuroimmunZ or the DABA assays, 28 sera concordantly so. Such false reactivity was influenced by the serotype of Dengue virus (DV) to which individuals had been exposed to. Thus, of sera from patients undergoing secondary Dengue virus infection of known serotype, 91%, 45% and 28% of Dengue virus serotype 2, 3 and 4 respectively were reactive in one or more of the three assays. A novel method of quenching false sero-reactivity was therefore developed for the DABA and IgG capture assays. Initial addition of a single homologous Dengue virus serotype 3 NS1Ag quench significantly ablated false reactivities in the pre-Zika period sera. An equipotent quadrivalent quench comprising homologous Dengue virus serotypes 1 to 4 NS1Ag was shown to be optimum yet retained sensitivity for the detection of specific anti-Zika antibody. Comparing DABA and IgG capture assays using quenched and unquenched conjugates in comparison with EuroimmunZ early in the course of PCR-confirmed infection indicated that a significant component of the apparent early anti-ZIKA antibody response is likely to be due to a Zika virus-driven anamnestic anti-Dengue virus response. The increased specificity provided by homologous antigen quenching is likely to provide a significant improvement in sero-diagnostics and to be of clinical value.

Background Infection with hepatitis E virus (HEV) Genotype 3 is recognized as a food-borne zoonosis in developed countries where it usually causes a mild self-limited acute hepatitis. It may cause a persistent infection in the immunosuppressed human that can progress to cirrhosis. To protect the patient from transfusion-acquired HEV infection, steps have been taken in the United Kingdom to provide for at-risk patients only components from donors screened for HEV viremia. This strategy does not protect from dietary exposure and calls into question estimation of relative risk between blood transfusion and diet. Study design and methods Using data on HEV viremia, component exposure, residual plasma volume, and resulting transmission, the dose of virus administered and subsequent transmission rates were determined and used to populate a model that can infer the relationship between blood and dietary exposure. Results The annual attack rate of a population, defined as seroconversion, provides an estimate of the risk of receiving a component containing HEV from a viremic donor. The lowest viral dose that resulted in infection was 2 × 104 IUs and 55% of components containing this dose transmitted infection. The transfusion risk of infection only exceeds the annual dietary risk when more than 13 individual donor components are transfused. Conclusion For many solid organ transplant patients dietary exposure far exceeds the risk of transfusion from unscreened donors. It is only in the immunosuppressed patient requiring extensive blood component support that transfusion risk dominates. This understanding should inform policy decisions on HEV RNA screening of blood donations.

Introduction Hepatitis E virus (HEV), the most common cause of acute hepatitis in many European countries, is transmitted through consumption of processed pork but also via blood transfusion and transplantation. HEV infection can become persistent in immunocompromised individuals. Aim We aimed to determine the incidence and epidemiology of HEV infection in English blood donors since the introduction of donation screening in 2016. Methods Between March 2016 and December 2017, 1,838,747 blood donations were screened for HEV RNA. Donations containing HEV RNA were further tested for serological markers, RNA quantification and viral phylogeny. Demographics, travel and diet history were analysed for all infected donors. Results We identified 480 HEV RNA-positive blood donations during the 22-month period, most (319/480; 66%) donors were seronegative. Viral loads ranged from 1 to 3,230,000 IU/ml. All sequences belonged to genotype 3, except one which likely represents a new genotype. Most viraemic donors were over 45 years of age (279/480; 58%), donors aged between 17 and 24 years had a seven-times higher incidence of HEV infection than other donors between March and June 2016 (1:544 donations vs 1:3,830). HEV-infected blood donors were evenly distributed throughout England. Screening prevented 480 HEV RNA-positive blood donations from reaching clinical supply. Conclusion HEV screening of blood donations is a vital step in order to provide safer blood for all recipients, but especially for the immunosuppressed. The unusually high rates of HEV infection in young blood donors may provide some insight into specific risks associated with HEV infection in England.

BACKGROUND Hepatitis E virus (HEV) Genotype 3 (G3) in England comprises two principal phylogenetic groups (Group 1 and Group 2) and can be transmitted by transfusion. Unselected screening identified 79 viremic donors; 76 participated in a follow-up study. STUDY DESIGN AND METHODS Viral RNA dynamics, phylogenetics, and seroconversion were characterized in the donors. Detailed demographic, travel, clinical, and lifestyle questionnaires were undertaken. RESULTS The majority of viremic individuals (57/79) were seronegative at time of donation but all seroconverted. Viremia was short-lived, with a median of 6.5 weeks to confirmed viral clearance. All infections were acquired in the United Kingdom and were G3, with Group 2 viruses predominating (43/54; 80%). Infection was associated with some clinical symptoms both at and after donation (8/77; 10%). Viral loads and symptoms were more pronounced in Group 1 infections. There was no serologic evidence of reinfection. Donors were more commonly male (p = 0.002); both male and female donors were older than comparator donors. Animal contact was unlikely to be the source of infection. Consumption of chicken and pig meat was common to all infected donors; processed pig meat was most commonly purchased from one particular retail chain. CONCLUSION Viremic donors represent primary infection in older members of the community and reflect a widespread zoonotic in the United Kingdom. The two phylogenetic groups of HEV G3 display different pathogenicity and the more common Group 2 appears less adapted to humans. There are no objective demographic criteria that can identify donors at enhanced HEV risk.

Zika virus (ZIKV) is a mosquito-borne flavivirus that emerged recently as a global health threat, causing a pandemic in the Americas. ZIKV infection mostly causes mild disease, but is linked to devastating congenital birth defects and Guillain-Barré syndrome in adults. The high level of cross-reactivity among flaviviruses and their cocirculation has complicated serological approaches to differentially detect ZIKV and dengue virus (DENV) infections, accentuating the urgent need for a specific and sensitive serological test. We previously generated a ZIKV nonstructural protein 1 (NS1)-specific human monoclonal antibody, which we used to develop an NS1-based competition ELISA. Well-characterized samples from RT-PCR-confirmed patients with Zika and individuals exposed to other flavivirus infections or vaccination were used in a comprehensive analysis to determine the sensitivity and specificity of the NS1 blockade-of-binding (BOB) assay, which was established in laboratories in five countries (Nicaragua, Brazil, Italy, United Kingdom, and Switzerland). Of 158 sera/plasma from RT-PCR-confirmed ZIKV infections, 145 (91.8%) yielded greater than 50% inhibition. Of 171 patients with primary or secondary DENV infections, 152 (88.9%) scored negative. When the control group was extended to patients infected by other flaviviruses, other viruses, or healthy donors (n = 540), the specificity was 95.9%. We also analyzed longitudinal samples from DENV-immune and DENV-naive ZIKV infections and found inhibition was achieved within 10 d postonset of illness and maintained over time. Thus, the Zika NS1 BOB assay is sensitive, specific, robust, simple, low-cost, and accessible, and can detect recent and past ZIKV infections for surveillance, seroprevalence studies, and intervention trials.

Routine viral-load (VL) testing of HIV-infected individuals on antiretroviral therapy (ART) is used to monitor treatment efficacy. However, due to logistical challenges, implementation of VL has been difficult in resource-limited settings. The aim of this study was to evaluate the performance of the SAMBA semi-Q (simple amplification-based assay semiquantitative test for HIV-1) in London, Malawi, and Uganda. The SAMBA semi-Q can distinguish between patients with VLs above and below 1,000 copies/ml. The SAMBA semi-Q was validated with diluted clinical samples and blinded plasma samples collected from HIV-1-positive individuals. SAMBA semi-Q results were compared with results from the Roche COBAS AmpliPrep/COBAS TaqMan HIV-1 test, v2.0. Testing of 96 2- to 10-fold dilutions of four samples containing HIV-1 subtype C as well as 488 samples from patients in the United Kingdom, Malawi, and Uganda yielded an overall accuracy for the SAMBA semi-Q of 99% (95% confidence interval [CI], 93.8 to 99.9%) and 96.9% (95% CI 94.9 to 98.3%), respectively, compared to to the Roche test. Analysis of VL data from patients in Malawi and Uganda showed that the SAMBA cutoff of 1,000 copies/ml appropriately distinguished treated from untreated individuals. Furthermore, analysis of the viral loads of 232 patients on ART in Malawi and Uganda revealed similar patterns for virological control, defined as either Antiretroviral Therapy for HIV Infection in Adults and Adolescents: Recommendations for a Public Health Approach , 2010). This study suggests that the SAMBA semi-Q has adequate concurrency with the gold standard measurements for viral load. This test can allow VL monitoring of patients on ART at the point of care in resource-limited settings.

Background & Aims Chronic hepatitis B (CHB) infection acquired perinatally or in early childhood has been associated with a prolonged phase of immune tolerance from viral exposure into early adulthood. The immune-tolerant phase of the disease is characterized by high levels of hepatitis B virus (HBV) DNA and normal liver biochemistry, with minimal or no fibrosis. We investigated whether the age of patients with CHB affects their antiviral immunity and whether children and young adults have a veritable state of immunologic tolerance. Methods We isolated T cells from different age groups of patients with CHB and used flow cytometric methods to measure production of effector and inflammatory cytokines (interferon, tumor necrosis factor, interleukin [IL]-17A, IL-22, and IL-8), T-helper (Th)2 cytokines (IL-10, IL-4), Th1 cytokines (IL-2 and IL-21), and the CC chemokine CCL3 (MIP-1). We also measured markers of T-cell exhaustion or inhibition (PD-1, LAG-3, TIM3, LAIR-1, and CTLA-4) and HBV-specific T cells. Results Young patients with CHB have a Th1-cell cytokine profile and a partial profile of T-cell exhaustion. Direct quantification of the HBV-specific T-cell response showed that young patients with CHB have more HBV-specific T cells with the ability to proliferate and produce cytokines than adult patients with CHB. Conclusions HBV infection in younger patients is not associated with an immune profile of T-cell tolerance. On the contrary, children and young adults with chronic HBV infection have an HBV-specific immune profile that is less compromised than that observed in older patients.

A.V. Lee, D.F. Bibby, H. Oakervee, A. Rohatiner, I. Ushiro-Lumb, D.A. Clark, F.M. Mattes. Nosocomial transmission of parainfluenza 3 virus in hematological patients characterized by molecular epidemiology. Transpl Infect Dis 2011: 13: 433–437. All rights reserved Abstract: We report an outbreak of parainfluenza 3 virus involving 17 hematology–oncology patients on 2 hospital wards. Sequence analysis of clinical samples confirmed homology of strains for 16/17 patients and 1 healthcare worker. Epidemiological analysis of the outbreak supported the molecular data with nosocomial transmission of the same genetic strain as the cause of the outbreak.

BACKGROUND For infectious disease risk assessment among deceased organ donors, pre-donation clinical, microbiological, and behavioral information are reviewed; however, uncertainty may arise due to false negative screening results of recently acquired infections. METHOD The burden of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV), and residual risks (RR) of undetected virus was estimated, with the impact of more sensitive screening. RESULTS For United Kingdom potential deceased organ donors between 2010 and 2014, prevalence of HBsAg was 0.1%, HIV 0.06% and HCV 0.9%, increasing to 25.7% in people who injected drugs (PWID). Incidence, derived from new blood donors, was multiplied by duration of screening assay window periods to give RR per 100 000 donors as 0.43 (95% confidence interval [CI] 0.03-3.99) for HBV, 0.08 (95% CI 0.02-0.21) for HIV, and 5.96 (95% CI 0.82-37.89) for HCV. For PWID, HCV RR was 163.3 (95% CI 22.8-1107.8) compared to 2.76 (95% CI 0.35-17.36) for non-PWID. RR decreased significantly with nucleic acid testing (NAT), and, for HCV, antigen testing had a similar impact. CONCLUSION While the burden of HCV risk lies within PWID, these are in small numbers therefore few HCV antigen or NAT tests would be needed to more accurately assess risk.

The prevalence of hepatitis B and hepatitis C in immigrant communities is unknown. Immigrants from south Asia are common in England and elsewhere, and the burden of viral hepatitis in these communities is unknown. We aimed to determine the prevalence of viral hepatitis in immigrants from south Asia living in England, and we therefore undertook a community-based testing project in such people at five sites in England. A total of 4998 people attending community centres were screened for viral hepatitis using oral fluid testing. The overall prevalence of anti-hepatitis C virus (HCV) in people of south Asian origin was 1.6% but varied by country of birth being 0.4%, 0.2%, 0.6% and 2.7% in people of this ethnic group born in the UK, India, Bangladesh and Pakistan, respectively. The prevalence of hepatitis B surface antigen was 1.2%-0.2%, 0.1%, 1.5% and 1.8% in people of this ethnic group born in the UK, India, Bangladesh and Pakistan, respectively. Analysis of risk factors for HCV infection shows that people from the Pakistani Punjab and those who have immigrated recently are at increased risk of infection. Our study suggests that migrants from Pakistan are at highest risk of viral hepatitis, with those from India at low risk. As prevalence varies both by country and region of origin and over time, the prevalence in migrant communities living in western countries cannot be easily predicted from studies in the country of origin.

Summary Objectives To investigate a nosocomial and community outbreak of hepatitis B to establish how the infections might have occurred. Study design Descriptive study. Methods Four cases of hepatitis B who had stayed in hospital during their incubation periods, a case in one of their household contacts, and three further cases in the community were all linked to a patient who had been infected during a renal transplant in India. Medical records from cases were reviewed to extract information about risk factors for infection. Working practices were reviewed to determine how nosocomial transmissions might have occurred. ‘Look-back’ exercises were conducted to identify and follow-up other patients and staff who might also be at-risk of infection. Hepatitis B viral sequences from all cases were examined to determine whether they were related. Results Viral DNA sequences from all nine cases were identical. The primary case had an extremely high viral load due to underlying immunosuppression. Three of the nosocomial transmissions occurred whilst the primary and secondary cases shared general medical wards; two whilst the primary case was in standard isolation. No clear routes of infection were identified. The fourth was associated with a failure of infection control in operating theatres. Conclusions Invasive medical procedures in high-prevalence countries carry a clear risk of blood borne viral infections. There is a need for much better awareness of this risk, both among patients who are considering travelling for treatment, and the health professionals who will be caring for them on their return. Infections may be preventable through hepatitis B vaccination. Patients admitted to hospital following invasive medical procedures in high-prevalence countries should be nursed with stringent infection control measures until blood borne viral infections can be excluded. However, patients with hepatitis B who are highly infectious may transmit the virus despite high standards of infection control.

Hepatitis E virus (HEV) Genotype 3 (G3) in England comprises two principal phylogenetic groups (Group 1 and Group 2) and can be transmitted by transfusion. Unselected screening identified 79 viremic donors; 76 participated in a follow-up study.Viral RNA dynamics, phylogenetics, and seroconversion were characterized in the donors. Detailed demographic, travel, clinical, and lifestyle questionnaires were undertaken.The majority of viremic individuals (57/79) were seronegative at time of donation but all seroconverted. Viremia was short-lived, with a median of 6.5 weeks to confirmed viral clearance. All infections were acquired in the United Kingdom and were G3, with Group 2 viruses predominating (43/54; 80%). Infection was associated with some clinical symptoms both at and after donation (8/77; 10%). Viral loads and symptoms were more pronounced in Group 1 infections. There was no serologic evidence of reinfection. Donors were more commonly male (p = 0.002); both male and female donors were older than comparator donors. Animal contact was unlikely to be the source of infection. Consumption of chicken and pig meat was common to all infected donors; processed pig meat was most commonly purchased from one particular retail chain.Viremic donors represent primary infection in older members of the community and reflect a widespread zoonotic in the United Kingdom. The two phylogenetic groups of HEV G3 display different pathogenicity and the more common Group 2 appears less adapted to humans. There are no objective demographic criteria that can identify donors at enhanced HEV risk.

Summary Background The prevalence of hepatitis E virus (HEV) genotype 3 infections in the English population (including blood donors) is unknown, but is probably widespread, and the virus has been detected in pooled plasma products. HEV-infected donors have been retrospectively identified through investigation of reported cases of possible transfusion-transmitted hepatitis E. The frequency of HEV transmission by transfusion and its outcome remains unknown. We report the prevalence of HEV RNA in blood donations, the transmission of the virus through a range of blood components, and describe the resulting morbidity in the recipients. Methods From Oct 8, 2012, to Sept 30, 2013, 225 000 blood donations that were collected in southeast England were screened retrospectively for HEV RNA. Donations containing HEV were characterised by use of serology and genomic phylogeny. Recipients, who received any blood components from these donations, were identified and the outcome of exposure was ascertained. Findings 79 donors were viraemic with genotype 3 HEV, giving an RNA prevalence of one in 2848. Most viraemic donors were seronegative at the time of donation. The 79 donations had been used to prepare 129 blood components, 62 of which had been transfused before identification of the infected donation. Follow-up of 43 recipients showed 18 (42%) had evidence of infection. Absence of detectable antibody and high viral load in the donation rendered infection more likely. Recipient immunosuppression delayed or prevented seroconversion and extended the duration of viraemia. Three recipients cleared longstanding infection after intervention with ribavirin or alteration in immunosuppressive therapy. Ten recipients developed prolonged or persistent infection. Transaminitis was common, but short-term morbidity was rare; only one recipient developed apparent but clinically mild post-transfusion hepatitis. Interpretation Our findings suggest that HEV genotype 3 infections are widespread in the English population and in blood donors. Transfusion-transmitted infections rarely caused acute morbidity, but in some immunosuppressed patients became persistent. Although at present blood donations are not screened, an agreed policy is needed for the identification of patients with persistent HEV infection, irrespective of origin, so that they can be offered antiviral therapy. Funding Public Health England and National Health Service Blood and Transplant.

We report a 20-month-old child with disseminated adenovirus infection after a haploidentical T cell-depleted stem cell transplantation. This case demonstrates the value of polymerase chain reaction surveillance for early detection of adenovirus infection and the role of quantitative polymerase chain reaction for monitoring antiviral therapy. It also emphasizes the importance of T cell immunity in controlling disseminated adenovirus infection after stem cell transplantation.

The Roche COBAS TaqMan HIV-1 version 1.0 (v1.0) real-time PCR test detects more low level viral loads (VL) compared to the previous Roche Amplicor version 1.5 assay. Due to under-quantification issues, the Roche TaqMan HIV-1 version 2.0 (v2.0) was introduced in 2009. Controversy remains on differences at the low VL end, where clinical decisions regarding possible viral escape are based.To compare the rate and size of VL blips with v1.0 and v2.0 in virologically suppressed patients and describe the impact of v2.0 on patient management.A cohort study of HIV-positive patients on antiretroviral therapy with a VL50 copies/ml at the beginning and end of the study period (July 2008-February 2010). VL blips were compared during two consecutive 9-month periods, initially measured by v1.0, then v2.0. Genotypic resistance testing and treatment switches were described.1037 of 2584 patients (73.1% male) with median age 43 years were included. 2465 VL samples were measured on v1.0 and 2206 on v2.0. 108 (10.4%) patients had blips on v1.0 (4.4% of samples) compared to 99 (9.5%) patients (4.5% of samples) on v2.0. Median log VL was 1.89 (78 copies/ml) for v1.0 and 2.06 (116 copies/ml) for v2.0 (p=0.002). Further characterisation of 11 samples detected no resistance and no treatment modifications were identified.TaqMan v1.0 and v2.0 have similar blip rates, while blips are higher with v2.0. This study supports the strategy to increase the threshold of concern for VL blips on v2.0.

Background A new nucleic acid-based assay (simple amplification-based assay [SAMBA]) for rapid visual detection of human immunodeficiency virus-type 1 (HIV-1) by dipstick is described. The assay was designed to be simple, stable, robust, self-contained, and capable of detecting a broad spectrum of HIV-1 subtypes and recombinant forms. Methods The performance of the SAMBA HIV-1 test (amplification and detection chemistry) was evaluated using the World Health Organization HIV-1 RNA Genotype Reference Panel, with clinical samples representing various viral subtypes and recombinant forms common in sub-Saharan Africa. Sixty-nine randomly selected and blinded clinical samples that had undergone HIV-1 genotypic resistance analyses in a large London teaching hospital were also tested. These samples included 14 different viral subtypes or recombinant forms with viral loads of 78-9.5 x 10(6) copies/mL. Results The sensitivity and viral subtype coverage of the SAMBA HIV-1 test were either comparable to or better than those of the commercially available nucleic acid-based HIV-1 diagnostic tests. Conclusions The unique characteristics and competitive performance of the SAMBA HIV-1 test render it suitable for point-of-care and near-patient testing in both developed and developing countries.

Objective To evaluate the performance of a new Chlamydia Rapid Test with vaginal swab specimens as a potential tool for chlamydia diagnosis and screening. Design Performance evaluation study. Settings A young people’s sexual health centre (site 1) and two genitourinary medicine clinics (sites 2 and 3) in the United Kingdom. Participants 1349 women aged between 16 and 54 attending one of the three clinics. Main outcome measures Sensitivity, specificity, positive predictive value, and negative predictive value of the Chlamydia Rapid Test versus polymerase chain reaction and strand displacement amplification assays; correlation between the Chlamydia Rapid Test visual signal and organism load; acceptability to participants of self collected vaginal swabs as the specimen type for Chlamydia testing. Results Polymerase chain reaction positivity rates for Chlamydia trachomatis infection were 8.4% (56/663) at site 1, 9.4% (36/385) at site 2, and 6.0% (18/301) at site 3. Compared with polymerase chain reaction assay, the resolved sensitivity, specificity, positive predictive value, and negative predictive value of the Chlamydia Rapid Test were 83.5% (91/109), 98.9% (1224/1238), 86.7% (91/105), and 98.6% (1224/1242). Compared with strand displacement amplification assay, sensitivity and specificity of the Chlamydia Rapid Test were 81.6% (40/49) and 98.3% (578/588). Organism load of self collected vaginal swabs ranged from 5.97×10 2 to 1.09×10 9 Chlamydia plasmids per swab, which correlated well with the Chlamydia Rapid Test’s visual signal ( r =0.6435, P Conclusions The performance of the Chlamydia Rapid Test with self collected vaginal swabs indicates that it would be an effective same day diagnostic and screening tool for Chlamydia infection in women. The availability of Chlamydia Rapid Test results within 30 minutes allows for immediate treatment and contact tracing, potentially reducing the risks of persistent infection and onward transmission. It could also provide a simple and reliable alternative to nucleic acid amplification tests in chlamydia screening programmes.

Objective: To characterise a Chlamydia trachomatis variant strain from a patient with non-gonococcal urethritis (NGU) whose first void urine (FVU) displayed discrepant C trachomatis test results and describe the clinical response to treatment. Methods: The FVU specimen was assayed with an immune based Chlamydia Rapid Test (CRT) and various nucleic acid amplification tests (NAATs) to establish C trachomatis infection. Sequencing of the major outer membrane protein gene (omp1 also known as ompA) was undertaken to identify the serovar of the variant strain. Polymerase chain reaction (PCR) analysis was also conducted to determine whether the strain harboured deletions in the cryptic plasmid or was plasmid free. Results: The FVU specimen was strongly reactive in CRT but negative with the plasmid based Amplicor PCR (Roche) and ProbeTec ET (Becton-Dickinson) assays. However, NAATs for 16S RNA (Aptima Combo 2, GenProbe), omp1 (RealArt CT PCR, Artus and in-house NAATs) or the outer membrane complex B protein gene (omcB) established C trachomatis infection. Sequencing of omp1 showed that the variant belonged to serovar I. PCR analysis indicated that the variant was plasmid free. The patient did not respond to single dose azithromycin treatment but subsequently responded to a course of doxycycline. Conclusions: A pathogenic plasmid free C trachomatis variant was identified. Clinicians should be alerted to the possibility of undetected C trachomatis infection caused by such variants and the potential of azithromycin failure in patients with recurrent chlamydial NGU. The occurrence of this variant is rare and should not form the basis for judgment of the performance or usefulness of plasmid based NAATs for C trachomatis detection.

Background & Aims: Approximately 20% of hepatitis C virus (HCV) patients develop cirrhosis from infection after about 20 years. The proportion of patients developing cirrhosis for longer than 30 years after infection is unknown. Our objectives were to determine the prevalence of HCV-related cirrhosis in a population of Asian patients who were infected in childhood 20 to 80 years ago and compare this with the prevalence of cirrhosis in Caucasian patients referred to the same hospitals. Methods: Retrospective analyses were performed of all patients who had detectable HCV-RNA levels and who attended local hospitals in northeast London between 1992 and 2003. Factors implicated in the development of cirrhosis were examined by multivariable analysis. Results: A total of 143 adult Asian patients who had been infected with HCV for many decades were compared with 239 Caucasian patients. The prevalence of cirrhosis increased with age. Of Asian patients aged 61–80 years (n = 55) 78% had cirrhosis, whereas 25% of Caucasian patients aged 61–80 years (n = 55) had cirrhosis. Multivariable linear analysis revealed that fibrosis progression and age were similar in both groups and the difference in the prevalence of cirrhosis was not explained by any unique Asian characteristic other than prolonged infection. Conclusions: The prevalence of cirrhosis in patients with chronic HCV increases with increasing duration of infection. In Asian patients infected at birth, infection for over 60 years causes cirrhosis in 71% of infected individuals. Because relationship between the severity of fibrosis and age in Asian patients is similar to that seen in Caucasian patients it is likely that similar rates of cirrhosis will be seen in other patients who are infected for more than 60 years.

The Department of Health (DH) estimates that approximately 0.4% of the UK population are chronically infected with hepatitis C virus (HCV) (that is, 200 000 people). As few as 10% of these individuals, who are at risk of end stage liver disease, are thought to be aware of their infection. Clearly action is required to identify and treat these patients with current drugs (pegylated interferons …

Introduction Stopping rules have been proposed for the early discontinuation of Pegylated-Interferon-α (PEG-IFN-α) therapy in those patients who are considered unlikely to respond. Recent studies have shown that no reduction in quantitative HBsAg and the absence of >2 log decline in HBV DNA at 12 weeks therapy can predict non-response. However, these data are almost exclusively from genotype A and D cohorts. Here we test how robust this strategy would be in clinical practice and whether this rule could be applied to a UK population of diverse HBV genotypes. Methods 49 patients (male=35) were treated with PEG-IFNα for CHB over the course of the study. Ten patients remain on therapy and eight patients discontinued due to poor compliance or intolerance. 31 patients (male=20), HBeAg positive (n=24), median age 31 (range 18–55) completed 48 weeks PEG-IFNα and were included in the analysis. HBV genotype was recorded for all patients (A=6, B=5, C=10, D=9, E=1). ALT, HBV DNA and HBsAg was quantified at baseline and longitudinally at 12-week intervals. Results Of the 31 patients, 10 were considered responders; seven were HBeAg positive and seroconverted on therapy and three were HBeAg negative pre-therapy and considered responders with sustained immune control off treatment. The decline in HBV DNA and qHBsAg by 12 weeks was 3.99 log, 0.17 log (HBeAg positive group) and 2.9 log, 0.5 log (HBeAg negative group) respectively. 16/31 patients were non-genotype A or D. Of the responders from this group there was a decline in HBV DNA and qHBsAg of 4.10 log and 0.58 log respectively by 12 weeks. On sub-group analysis by genotype, there was no statistically significant difference in HBV DNA and qHBsAg decline at 12 weeks across all genotypes, when comparing HBV DNA and qHBsAg between genotype A and D and non A and D patients (p=0.40 and 1.0 respectively). More over adopting the rule of >2 log decline in HBV DNA and no decline in qHBsAg by 12 weeks, reveals we would not exclude those likely to respond; as all responders achieve the outlined viral response by 12 weeks therapy. Conclusion These data highlight the utility of this stopping rule for PEG-IFNα across all genotypes. The absence of >2 log decline in HBV DNA and reduction in qHBsAg at 12 weeks therapy makes a favourable response unlikely. This rule should be adopted in clinical practice to avoid poorly tolerated side effects and the cost of completing 48 weeks therapy. Furthermore, this 12-week milestone would allow the early switch to an oral antiviral in PEG-IFNα non-responders. Competing interests None declared.

Introduction Stopping-rules now exist for Pegylated Interferon-α (PEG-IFNα) treated Chronic Hepatitis B (CHB) patients. Despite the utility of such strategies, the immunological mechanisms that drive HBV DNA and HBsAg decline remain poorly understood. Recent data have identified changes in a subset of NK cells in HBeAg negative disease, which may determine treatment response. However, HBeAg positive disease responds more favourably to PEG-IFNα; here we report on a longitudinal analysis of changes in the immune profile in this cohort, to define the effects of PEG-IFNα on innate immunity. Methods PBMCs from a cohort of 17 HBeAg positive patients followed longitudinally at 3 monthly intervals pre, during and post PEG-IFNα therapy were utilised. Phenotypic analysis of NK cells was performed by multicolour flow cytometry. Changes in the immune responses were correlated with simultaneous measurements of ALT, HBV DNA and quantitative HBsAg levels (Abbott ARCHITECT). Results PEG-IFNα increased CD56 bright NK cells by fourfold (mean fold change; MFC 3.7, p=0.0001). This was parallelled by the activation and proliferation of this subset, as marked by HLA-DR and Ki67 expression respectively (MFC 1.5 and 2.3, p=0.009 and p=0.0001 respectively). This increase was more marked at 48 weeks treatment, correlating with a nadir of HBV DNA and HBsAg. The activating (NKG2C and NKp30) and inhibitory (NKG2A) receptors were also analysed in this population. A twofold increase in NKp30 expression (MFC 2.27, p=0.04) was seen which was maximal at 48 weeks, while no significant change was noted for NKG2A and NKG2C. There was a twofold up-regulation of TRAIL expression on CD56 bright NK cells, which temporally correlated with ALT levels, (MFC 1.8, p=0.0001), this effect was most dramatic at 24 weeks of therapy and sustained to 48 weeks. Conclusion PEG-IFNα therapy in this cohort enhances and activates CD56 bright NK cells. Similarly, TRAIL and NKp30 expression is augmented and sustained throughout treatment and all these effects are maximal at 48 weeks. The restorative innate immune changes begin early and increase throughout therapy in all patients. Thus, 48 weeks therapy may provide the optimal immunological conditions to introduce an oral-antiviral to achieve disease control in PEG-IFNα non-responders. Competing interests None declared.