Investigation of hospital discharge cases and SARS-CoV-2 introduction into Lothian care homes.

BACKGROUND: The first epidemic wave of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Scotland resulted in high case numbers and mortality in care homes. In Lothian, over one-third of care homes reported an outbreak, while there was limited testing of hospital patients discharged to care homes. AIM: To investigate patients discharged from hospitals as a source of SARS-CoV-2 introduction into care homes during the first epidemic wave. METHODS: A clinical review was performed for all patients discharges from hospitals to care homes from 1st March 2020 to 31st May 2020. Episodes were ruled out based on coronavirus disease 2019 (COVID-19) test history, clinical assessment at discharge, whole-genome sequencing (WGS) data and an infectious period of 14 days. Clinical samples were processed for WGS, and consensus genomes generated were used for analysis using Cluster Investigation and Virus Epidemiological Tool software. Patient timelines were obtained using electronic hospital records. FINDINGS: In total, 787 patients discharged from hospitals to care homes were identified. Of these, 776 (99%) were ruled out for subsequent introduction of SARS-CoV-2 into care homes. However, for 10 episodes, the results were inconclusive as there was low genomic diversity in consensus genomes or no sequencing data were available. Only one discharge episode had a genomic, time and location link to positive cases during hospital admission, leading to 10 positive cases in their care home. CONCLUSION: The majority of patients discharged from hospitals were ruled out for introduction of SARS-CoV-2 into care homes, highlighting the importance of screening all new admissions when faced with a novel emerging virus and no available vaccine.

Comparing Sex-Specific Outcomes After Medial Patellofemoral Ligament Reconstruction for Patellar Instability: A Systematic Review.

BACKGROUND: The impact of patient sex on outcomes after medial patellofemoral ligament ligament reconstruction (MPFLR) has not been well studied. PURPOSE: To conduct a systematic review to determine sex-based differences in outcomes after MPFLR for patellar instability and the proportion of studies examining this as a primary or secondary purpose. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A systematic review was performed using the PubMed, Cochrane Library, PubMed Central, Ovid, and Embase databases according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were included if they were written in English, were performed on humans, consisted of patients who underwent MPFLR with allograft or autograft, evaluated at least 1 of the selected outcomes comparing male and female patients, and had statistical analysis available for relevant findings. Excluded were case reports, review studies or systematic reviews, studies that did not evaluate at least 1 sex-specific outcome, studies that included other injuries associated with patellofemoral instability injury, cadaveric studies, and those in which patients underwent concomitant procedures. RESULTS: The initial search yielded 3470 studies; 2647 studies remained after removing duplicates. Of the 401 studies that underwent full-text review, 10 met all inclusion criteria and were included for quantitative analysis. A meta-analysis could not be performed given the heterogeneity within the data set. Of the 2647 studies evaluated in this study, only 2 (0.08%) studies examined the impact of patient sex on MPFLR outcomes as a primary purpose and only 8 (0.30%) studies explored it as a secondary purpose. CONCLUSION: Only 0.38% of the articles compared outcomes between male and female patients after MPFLR. The limited data available were too heterogenous to draw any concrete conclusions about the impact of patient sex on outcomes after MPFLR. Further research in this area is warranted, as findings may influence treatment plans and improve patient outcomes.

National population prevalence of antibodies to SARS-CoV-2 among pregnant women in Scotland during the second wave of the COVID-19 pandemic: a prospective national serosurvey.

OBJECTIVES: This study aimed to determine SARS-CoV-2 seroprevalence among pregnant women in the Scottish population during the second wave of the COVID-19 pandemic. STUDY DESIGN: Prospective national serosurvey. METHODS: We tested 13,428 residual samples retrieved from pregnant women participating in the first trimester combined ultrasound and biochemical screening for fetal trisomy across Scotland for SARS-CoV-2 antibodies over a 6-month period from November 2020 to April 2021. Seroprevalence estimates were adjusted for the sensitivity and specificity of the assays and weighted to reference populations. RESULTS: Seroprevalence rates in the antenatal samples significantly increased from 5.5% (95% confidence interval [CI] 4.7%-6.5%) in the 5-week period up to and including International Organization for Standardization (ISO) Week 51 (w/b Monday 14 December 2020) to 11.3% (95% CI 10.1%-12.6%) in the 5-week period up to and including ISO Week 14 (w/b Monday 5 April 2021). Increasing seroprevalence trends across the second wave were observed among all age groups. CONCLUSIONS: By the end of the second wave of the COVID-19 pandemic, approximately one in 10 women tested around the end of the first trimester of pregnancy had antibodies to SARS-CoV-2, suggesting that the vast majority were still susceptible to COVID-19 as they progressed to the later stages of pregnancy, when risks from infection are elevated for both mother and baby.

National population prevalence of antibodies to SARS-CoV-2 in Scotland during the first and second waves of the COVID-19 pandemic.

OBJECTIVES: Studies that measure the prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ('seroprevalence') are essential to understand population exposure to SARS-CoV-2 among symptomatic and asymptomatic individuals. We aimed to measure seroprevalence in the Scottish population over the course of the COVID-19 pandemic - from before the first recorded case in Scotland through to the second pandemic wave. STUDY DESIGN: The study design of this study is serial cross sectional. METHODS: We tested 41,477 residual samples retrieved from primary and antenatal care settings across Scotland for SARS-CoV-2 antibodies over a 12-month period from December 2019-December 2020 (before rollout of COVID-19 vaccination). Five-weekly rolling seroprevalence estimates were adjusted for the sensitivity and specificity of the assays and weighted to reference populations. Temporal trends in seroprevalence estimates and weekly SARS-CoV-2 notifications were compared. RESULTS: Five-weekly rolling seroprevalence rates were 0% until the end of March, when they increased contemporaneously with the first pandemic wave. Seroprevalence rates remained stable through the summer (range: 3%-5%) during a period of social restrictions, after which they increased concurrently with the second wave, reaching 9.6% (95% confidence interval [CI]: 8.4%-10.8%) in the week beginning 28th December in 2020. Seroprevalence rates were lower in rural vs. urban areas (adjusted odds ratio [AOR]: 0.70, 95% CI: 0.61-0.79) and among individuals aged 20-39 years and 60 years and older (AOR: 0.74, 95% CI: 0.64-0.86; AOR: 0.80, 95% CI: 0.69-0.91, respectively) relative to those aged 0-19 years. CONCLUSIONS: After two waves of the COVID-19 pandemic, less than one in ten individuals in the Scottish population had antibodies to SARS-CoV-2. Seroprevalence may underestimate the true population exposure as a result of waning antibodies among individuals who were infected early in the first wave.

Increasing drug-related mortality rates over the last decade in Scotland are not just due to an ageing cohort: A retrospective longitudinal cohort study.

BACKGROUND: In Europe, North America, and Australia, mortality due to drug-related (DR) causes amongst people who inject drugs (PWID) is a major issue. Our objective was to characterise temporal trends in DR mortality rates in a large cohort of PWID in Scotland over the past decade, all of whom had been diagnosed with hepatitis C virus (HCV) infection, and to investigate factors associated with DR mortality. METHODS: Retrospective longitudinal cohort study linking Scotland's national HCV Diagnosis Database and deaths registry. The study cohort consisted of all individuals with likely injection drug use-related route of HCV acquisition, who had been diagnosed with HCV between 1991 and 2018, and were alive and aged under 65 years on 1 January 2009. We used Lexis expansion to adjust for ageing cohort effects and calculated the mortality rate from an underlying/contributing DR cause over the period 2009-2018. We fitted Poisson regression models to estimate the temporal trend adjusting for attained age, sex, referral setting, region, and viraemic status at baseline. RESULTS: Amongst the study population (n = 35,065; 236,914 person-years), a total of 1900 DR deaths occurred; the DR mortality rate increased from 5.6/1000 [101 deaths] in 2009 to 12.4/1000 [342] person-years in 2018. Increasing trends were observed for all age-groups except 55-64 years. The overall DR mortality rate was highest for referrals for HCV testing from prison (11.0/1000) and hospital settings (10.0/1000). Mortality increased with calendar time period, with significantly raised adjusted rate ratios (RRs) from 2015 (RR=1.40, 95% CI:1.16-1.69) to 2018 (RR=2.23, 95% CI:1.88-2.64), compared with 2011-2012, for older age (35-44: RR=1.37, 95% CI:1.20-1.56; 45-54: RR=1.32, CI:1.14-1.53) compared with <35 years, for persons diagnosed with HCV since 2009 (RR=1.34, 95% CI:1.21-1.49), and for prison and hospital referrals (RRs of 1.30, 1.37) compared with GP referrals. CONCLUSION: Increasing DR mortality rates in Scotland over the past decade are not just due to an ageing cohort. Harm reduction services will likely need to expand and adapt to reverse the recent upward trends in DR mortality in PWID.

Increased case-finding and uptake of direct-acting antiviral treatment essential for micro-elimination of hepatitis C among people living with HIV: a national record linkage study.

OBJECTIVES: Micro-elimination of hepatitis C virus (HCV) in people living with HIV (PLHIV) and co-infected with HCV has been proposed as a key contribution to the overall goal of HCV elimination. While other studies have examined micro-elimination in HIV-treated cohorts, few have considered HCV micro-elimination among those not treated for HIV or at a national level. METHODS: Through data linkage of national and sentinel surveillance data, we examined the extent of HCV testing, diagnosis and treatment among a cohort of PLHIV in Scotland identified through the national database of HIV-diagnosed individuals, up to the end of 2017. RESULTS: Of 5018 PLHIV, an estimated 797 (15%) had never been tested for HCV and 70 (9%) of these had undiagnosed chronic HCV. The odds of never having been tested for HCV were the highest in those not on HIV treatment [adjusted odds ratio (aOR) = 7.21, 95% confidence interval (CI): 5.15-10.10). Overall HCV antibody positivity was 11%, and it was at its highest among people who inject drugs (49%). Most of those with chronic HCV (91%) had attended an HCV treatment clinic but only half had been successfully treated (54% for those on HIV treatment, 12% for those not) by the end of 2017. The odds of never having been treated for HCV were the highest in those not on HIV treatment (aOR = 3.60, 95% CI: 1.59-8.15). CONCLUSIONS: Our data demonstrate that micro-elimination of HCV in PLHIV is achievable but progress will require increased effort to engage and treat those co-infected, including those not being treated for their HIV.

Recurrent outbreaks of mumps in Lothian and the impact of waning immunity.

Another large outbreak of mumps occurred in Lothian from October 2017, which coincided with the commencement of the higher education term. During this period 324 cases were notified, most of whom were aged 18-22 years old. Although previous outbreaks had a focus in student populations, 43% of current cases reported that they were not a student. There has been increases in private student housing where students from all universities live, which may have contributed to the wide spread of the outbreak and complicated outbreak control. Information on vaccination status was available for 244 cases (75%), of whom the majority (75.8%) reported having two MMR doses. To investigate potential waning vaccine immunity the mean length of time since last mumps containing vaccine was calculated as 14.3 years. The outbreak was declared over in May 2018 after case numbers returned to background levels. This outbreak highlighted that mumps outbreaks occur cyclically coinciding with new cohorts of susceptible students entering the Lothian population. The lessons from this outbreak are to encourage students to have two MMR doses and also be prepared for mumps outbreaks in the near future. In future outbreaks the utility of a third MMR for outbreak control could be examined.

A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts.

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10-5 ). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.

Assessing the impact of mailing self-sampling kits for human papillomavirus testing to unscreened non-responder women in Manitoba.

Background: CervixCheck, Manitoba's cervical cancer screening program, conducted a pilot study to assess whether screening participation could be improved in unscreened women by offering a mailed self-sampling kit for human papillomavirus (hpv) testing instead of a Pap test. Methods: In a prospective cohort study design, a sample of unscreened women (n = 1052) who had been sent an invitation letter from CervixCheck in the past but who did not respond were randomized to either an intervention group or a control group. The intervention group received a mailed hpv self-sampling kit; the control group received no additional communication. Returned hpv self-sampling swabs were analyzed by a provincial laboratory. After 6 months, screening participation in the two study groups was compared using a logistic regression model adjusted for age and area of residence (urban or rural). Secondary outcomes included hpv positivity, specimen inadequacy, compliance with follow-up, and time to colposcopy. Results: Screening participation was significantly higher in the intervention group than in the control group (n = 51, 9.6%, vs. n = 13, 2.5%; odds ratio: 4.7; 95% confidence interval: 2.56 to 8.77). Geographic area of residence (urban or rural) and age were not statistically significant. Conclusions: The study demonstrated that hpv self-sampling kits can enhance screening participation in unscreened non-responder women in the setting of an organized screening program. Next steps should include additional research to determine the best implementation strategy for hpv self-sampling in Manitoba.

Evaluation of Staphylococcus aureus eradication therapy in orthopaedic surgery.

PURPOSE: Despite WHO recommendations, there is currently no national screening and eradication policy for the detection of methicillin-sensitive Staphylococcus aureus (MSSA) in the UK prior to elective orthopaedic surgery. This study aimed to evaluate the effectiveness of current standard methicillin-resistant S. aureus (MRSA) eradication therapies in the context of S. aureus (both MRSA and MSSA) decolonization in an elective orthopaedic population. METHODOLOGY: A total of 100 patients awaiting joint replacement surgery who were positive for S. aureus on PCR nasal screening underwent the current standard MRSA pre-operative decolonization regimen for 5 days. Prior to commencement of the eradication therapy, swabs of the anterior nares, throat and perineum were taken for culture. Further culture swabs were taken at 48-96 h following treatment, at hospital admission for surgery and at hospital discharge. Following the completion of treatment, patients were asked to provide feedback on their experience using Likert rating scales. The primary outcome of this study was S. aureus clearance 48-96 h following eradication treatment.Results/Key Findings. Clearance of S. aureus 48-96 h following treatment was 94 % anterior nares, 66 % throat and 88 % groin. Mean completion with nasal mupirocin was 98 %. There was no statistically significant recolonization effect between the end of the eradication treatment period and the day of surgery (P>0.05) at a median time of 10 days. CONCLUSION: Current MRSA decolonisation regimens are well tolerated and effective for MSSA decolonization for the anterior nares and groin. The decolonization effect is preserved for at least 10 days following treatment.

Imported case of measles in a university setting leading to an outbreak of measles in Edinburgh, Scotland from September to December 2016.

In September 2016, an imported case of measles in Edinburgh in a university student resulted in a further 17 confirmed cases during October and November 2016. All cases were genotype D8 and were associated with a virus strain most commonly seen in South East Asia. Twelve of the 18 cases were staff or students at a university in Edinburgh and 17 cases had incomplete or unknown measles mumps rubella (MMR) vaccination status. The public health response included mass follow-up of all identified contacts, widespread communications throughout universities in Edinburgh and prompt vaccination clinics at affected campuses. Imported cases of measles pose a significant risk to university student cohorts who may be undervaccinated, include a large number of international students and have a highly mobile population. Public health departments should work closely with universities to promote MMR uptake and put in place mass vaccination plans to prevent rapidly spreading measles outbreaks in higher educational settings in future.

Underestimation of Staphylococcus aureus (MRSA and MSSA) carriage associated with standard culturing techniques: One third of carriers missed.

OBJECTIVES: Nasal carriers of Staphylococcus (S.) aureus (MRSA and MSSA) have an increased risk for healthcare-associated infections. There are currently limited national screening policies for the detection of S. aureus despite the World Health Organization's recommendations. This study aimed to evaluate the diagnostic performance of molecular and culture techniques in S. aureus screening, determine the cause of any discrepancy between the diagnostic techniques, and model the potential effect of different diagnostic techniques on S. aureus detection in orthopaedic patients. METHODS: Paired nasal swabs for polymerase chain reaction (PCR) assay and culture of S. aureus were collected from a study population of 273 orthopaedic outpatients due to undergo joint arthroplasty surgery. RESULTS: The prevalence of MSSA nasal colonization was found to be between 22.4% to 35.6%. The current standard direct culturing methods for detecting S. aureus significantly underestimated the prevalence (p = 0.005), failing to identify its presence in approximately one-third of patients undergoing joint arthroplasty surgery. CONCLUSION: Modelling these results to national surveillance data, it was estimated that approximately 5000 to 8000 S. aureus surgical site infections could be prevented, and approximately $140 million to $950 million (approximately £110 million to £760 million) saved in treatment costs annually in the United States and United Kingdom combined, by using alternative diagnostic methods to direct culture in preoperative S. aureus screening and eradication programmes.Cite this article: S. T. J. Tsang, M. P. McHugh, D. Guerendiain, P. J. Gwynne, J. Boyd, A. H. R. W. Simpson, T. S. Walsh, I. F. Laurenson, K. E. Templeton. Underestimation of Staphylococcus aureus (MRSA and MSSA) carriage associated with standard culturing techniques: One third of carriers missed. Bone Joint Res 2018;7:79-84. DOI: 10.1302/2046-3758.71.BJR-2017-0175.R1.

Prevalence of mixed genotype hepatitis C virus infections in the UK as determined by genotype-specific PCR and deep sequencing.

The incidence of mixed genotype hepatitis C virus (HCV) infections in the UK is largely unknown. As the efficacy of direct-acting antivirals is variable across different genotypes, treatment regimens are tailored to the infecting genotype, which may pose issues for the treatment of underlying genotypes within undiagnosed mixed genotype HCV infections. There is therefore a need to accurately diagnose mixed genotype infections prior to treatment. PCR-based diagnostic tools were developed to screen for the occurrence of mixed genotype infections caused by the most common UK genotypes, 1a and 3, in a cohort of 506 individuals diagnosed with either of these genotypes. The overall prevalence rate of mixed infection was 3.8%; however, this rate was unevenly distributed, with 6.7% of individuals diagnosed with genotype 3 harbouring genotype 1a strains and only 0.8% of samples from genotype 1a patients harbouring genotype 3 (P < .05). Mixed infection samples consisted of a major and a minor genotype, with the latter constituting less than 21% of the total viral load and, in 67% of cases, less than 1% of the viral load. Analysis of a subset of the cohort by Illumina PCR next-generation sequencing resulted in a much greater incidence rate than obtained by PCR. This may have occurred due to the nonquantitative nature of the technique and despite the designation of false-positive thresholds based on negative controls.

An outbreak of mumps with genetic strain variation in a highly vaccinated student population in Scotland.

An outbreak of mumps within a student population in Scotland was investigated to assess the effect of previous vaccination on infection and clinical presentation, and any genotypic variation. Of the 341 cases, 79% were aged 18-24. Vaccination status was available for 278 cases of whom 84% had received at least one dose of mumps containing vaccine and 62% had received two. The complication rate was 5·3% (mainly orchitis), and 1·2% were admitted to hospital. Genetic sequencing of mumps virus isolated from cases across Scotland classified 97% of the samples as genotype G. Two distinct clusters of genotype G were identified, one circulating before the outbreak and the other thereafter, suggesting the virus that caused this outbreak was genetically different from the previously circulating virus. Whilst the poor vaccine effectiveness we found may be due to waning immunity over time, a contributing factor may be that the current mumps vaccine is less effective against some genotypes. Although the general benefits of the measles-mumps-rubella (MMR) vaccine should continue to be promoted, there may be value in reassessing the UK vaccination schedule and the current mumps component of the MMR vaccine.

Comparison of ePlex Respiratory Pathogen Panel with Laboratory-Developed Real-Time PCR Assays for Detection of Respiratory Pathogens.

Infections of the respiratory tract can be caused by a diversity of pathogens, both viral and bacterial. Rapid microbiological diagnosis ensures appropriate antimicrobial therapy as well as effective implementation of isolation precautions. The ePlex respiratory pathogen panel (RP panel) is a novel molecular biology-based assay, developed by GenMark Diagnostics, Inc. (Carlsbad, CA), to be performed within a single cartridge for the diagnosis of 25 respiratory pathogens (viral and bacterial). The objective of this study was to compare the performance of the RP panel with those of laboratory-developed real-time PCR assays, using a variety of previously collected clinical respiratory specimens. A total of 343 clinical specimens as well as 29 external quality assessment (EQA) specimens and 2 different Middle East respiratory syndrome coronavirus isolates have been assessed in this study. The RP panel showed an agreement of 97.4% with the real-time PCR assay regarding 464 pathogens found in the clinical specimens. All pathogens present in clinical samples and EQA samples with a threshold cycle (CT ) value of <30 were detected correctly using the RP panel. The RP panel detected 17 additional pathogens, 7 of which could be confirmed by discrepant testing. In conclusion, this study shows excellent performance of the RP panel in comparison to real-time PCR assays for the detection of respiratory pathogens. The ePlex system provided a large amount of useful diagnostic data within a short time frame, with minimal hands-on time, and can therefore potentially be used for rapid diagnostic sample-to-answer testing, in either a laboratory or a decentralized setting.

Multicenter Evaluation of the Cepheid Xpert Hepatitis C Virus Viral Load Assay.

Viral load monitoring for hepatitis C virus (HCV) is necessary to diagnose infection and monitor response to therapy, but the tests involved are currently confined to specialist institutions. There is a need for a fast, accurate assay with limited operator input to enhance the access to viral load monitoring. We evaluated the quantification of HCV RNA in serum and plasma by the Cepheid Xpert HCV Viral Load assay in comparison to the Abbott RealTime HCV assay. Serum and plasma samples were gathered from HCV-infected individuals at four international sites. These were tested with the Xpert HCV Viral Load assay, and results were compared to quantification by the Abbott RealTime HCV assay. An external quality assessment panel of eight samples was also tested. In total, 614 samples were analyzed in the study, and the qualitative results agreed on the two platforms for 588 (95.8%) samples. Further analysis of 396 samples quantified by both tests showed strong correlation (correlation coefficient r = 0.99) across the quantifiable range, with Bland-Altman plot data showing a mean difference (±1.96 standard deviation) of 0.03 ± 0.44 log10 IU/ml. In the external quality assessment panel, the Xpert HCV Viral Load assay results (quantified in log10 IU per milliliter) were within 1 standard deviation of the target value for all but one sample, which was also similarly misquantified by the Abbott RealTime HCV assay. The Xpert HCV Viral Load assay performs well compared to a market-leading HCV viral load test and should be considered for instances where rapid near-to-patient testing is required.

Multi-site clinical evaluation of the Xpert(®) HIV-1 viral load assay.

BACKGROUND: The most important reason for measuring HIV-1 viral load (VL) is to monitor the effectiveness of antiretroviral therapy (ART), both for the initial therapeutic response and sustained responses. Maintaining low or undetectable HIV-1 VL levels can reduce both the risks of progression to AIDS and transmission of infection to others. OBJECTIVES: To evaluate the diagnostic accuracy of Xpert(®) HIV-1 Viral Load (VL) assay compared to the Abbott RealTime HIV-1 assay, including assessing specificity by testing plasma specimens from confirmed HIV-1 negative blood donors. STUDY DESIGN: Subjects were enrolled from 4 participating sites, 2 in Europe and 2 in the USA. Fresh plasma samples were tested prospectively, while frozen plasma samples were collected prospectively, and tested retrospectively after selection of specimens to cover the assay's quantification range (40cp/mL-10,000,000 cp/mL). Eligibility criteria included a clinician ordered HIV-1 VL test from a confirmed HIV-1 positive adult (≥18 years) with a known antiviral treatment status. Exclusion criteria included previous enrollment in this study or improper specimen collection. Human blood donor specimens determined to be HIV-1 negative by standard blood bank antibody and nucleic acid amplification methods were used to assess specificity. RESULTS: Of the 764 specimens collected, 752 were eligible for inclusion but 5 were not tested by the Xpert, leaving 747 specimens tested (28.2% from females and 71.8% from males). Valid results were obtained for 724/747 (96.9%) specimens tested using the Xpert HIV-1 VL assay. The Xpert HIV-1 VL assay detected or quantified 568/724 (78.5%) specimens, while the RealTime HIV-1 assay detected or quantified 559/724 (77.2%). Of the 724 specimens tested by both assays, 390 were quantified by both assays and showed strong correlation: r=0.9847, with an R(2)=0.9696. Bland-Altman analysis showed good agreement between the two assays (381/390; 97.7%) with a distribution within 0.5 log10 cp/mL centered around zero. Xpert yielded VLs for 393 (80%) of the 494 quantifiable samples by Abbott. VLs of those specimens quantified by one of the assays, and either detected but not quantified or not detected by the other assay were all <170cp/mL. Specificity of the Xpert assay was found to be 100% (109/109), 95% CI: 96.7-100.0. CONCLUSION: Very good correlation was seen between the Xpert HIV-1 VL and Abbott RealTime HIV-1 assays, with added benefits for Xpert HIV-1 VL of: (1) lot-to-lot consistency traceable to WHO International Standard, (2) requiring both high and low level internal controls to be in range to have a valid result, (3) use of a single HIV-1 target for PCR and (4) faster turn-around-time for results, no need to wait to do batch testing of specimens. In summary, Xpert HIV-1 VL generated accurate VL results that if implemented could allow for actionable and timely treatment decisions during the same clinic visit. This scenario could reduce the loss to follow up often seen when these test results take days to weeks to become available to the clinician and patient.

Fatal disseminated varicella zoster infection following zoster vaccination in an immunocompromised patient.

A 79-year-old man with chronic lymphocytic leukaemia presented with fever and a widespread vesicular rash on 19 November 2014. The patient had not been under immunosuppressive regime for 6 months. He had received a shingles vaccine on 14th October and developed flu-like symptoms after 2 weeks. Intravenous antimicrobial therapy including aciclovir was started. He remained stable with no evidence of systemic involvement. On day 5, he developed respiratory and renal failure that required transfer to intensive care unit. Vesicle fluid, bronchoalveolar lavage and plasma were positive for varicella zoster virus by PCR. Slight clinical improvement allowed extubation on day 16. He subsequently deteriorated and died on day 25. Multiorgan failure was considered the immediate cause of death whereas disseminated varicella zoster infection was stated in the medical certificate as the other condition leading to this outcome. Varicella zoster Oka vaccine strain was detected in vesicle fluid, using PCR.

Low-pathogenicity Mycoplasma spp. alter human monocyte and macrophage function and are highly prevalent among patients with ventilator-acquired pneumonia.

BACKGROUND: Ventilator-acquired pneumonia (VAP) remains a significant problem within intensive care units (ICUs). There is a growing recognition of the impact of critical-illness-induced immunoparesis on the pathogenesis of VAP, but the mechanisms remain incompletely understood. We hypothesised that, because of limitations in their routine detection, Mycoplasmataceae are more prevalent among patients with VAP than previously recognised, and that these organisms potentially impair immune cell function. METHODS AND SETTING: 159 patients were recruited from 12 UK ICUs. All patients had suspected VAP and underwent bronchoscopy and bronchoalveolar lavage (BAL). VAP was defined as growth of organisms at >10(4) colony forming units per ml of BAL fluid on conventional culture. Samples were tested for Mycoplasmataceae (Mycoplasma and Ureaplasma spp.) by PCR, and positive samples underwent sequencing for speciation. 36 healthy donors underwent BAL for comparison. Additionally, healthy donor monocytes and macrophages were exposed to Mycoplasma salivarium and their ability to respond to lipopolysaccharide and undertake phagocytosis was assessed. RESULTS: Mycoplasmataceae were found in 49% (95% CI 33% to 65%) of patients with VAP, compared with 14% (95% CI 9% to 25%) of patients without VAP. Patients with sterile BAL fluid had a similar prevalence to healthy donor BAL fluid (10% (95% CI 4% to 20%) vs 8% (95% CI 2% to 22%)). The most common organism identified was M. salivarium. Blood monocytes from healthy volunteers incubated with M. salivarium displayed an impaired TNF-α response to lipopolysaccharide (p=0.0003), as did monocyte-derived macrophages (MDMs) (p=0.024). MDM exposed to M. salivarium demonstrated impaired phagocytosis (p=0.005). DISCUSSION AND CONCLUSIONS: This study demonstrates a high prevalence of Mycoplasmataceae among patients with VAP, with a markedly lower prevalence among patients with suspected VAP in whom subsequent cultures refuted the diagnosis. The most common organism found, M. salivarium, is able to alter the functions of key immune cells. Mycoplasmataceae may contribute to VAP pathogenesis.