BACKGROUND AND AIM:Varicella zoster virus (VZV) is a neurotropic herpesvirus. With improved access to molecular diagnostics, there is increasing recognition of VZV with central nervous system involvement. This study aimed to describe the demographic, clinical and treatment characteristics of patients admitted to an Australian tertiary hospital with VZV central nervous system infection. METHODS:Retrospective study of all adult patients (aged ≥18 years) presenting to an Australian tertiary hospital between November 2010 and May 2023 with a clinical syndrome of or imaging consistent with meningitis or encephalitis and detectable VZV DNA in cerebrospinal fluid using polymerase chain reaction. RESULTS:There were 48 cases of VZV meningitis and 13 cases of VZV encephalitis identified during the study period. The median age of patients with VZV meningitis and encephalitis was 34 years (range 21-86 years) and 73 years (range 22-94 years) respectively. All patients with VZV encephalitis and 37 of 48 (77.1%) with meningitis received intravenous (IV) acyclovir. Eight patients with VZV meningitis were treated with oral antivirals alone and seven were managed without antivirals or with ≤48 h of empiric antiviral therapy only; none of these patients experienced an adverse clinical outcome. Two patients with VZV encephalitis died. Seven patients experienced neurological complications, three with VZV meningitis and four with VZV encephalitis. Age and length of stay were associated with adverse clinical outcomes. CONCLUSION:VZV encephalitis predominates in older patients while VZV meningitis predominates in younger patients. IV acyclovir remains the standard of care for treatment of VZV encephalitis; however, its role in VZV meningitis is less clear. Controlled trials should be conducted to inform its use, particularly in low-risk patients with VZV meningitis.

BACKGROUND:There has been high uptake of rapid antigen test device use for point-of-care COVID-19 diagnosis. Individuals who are symptomatic but test negative on COVID-19 rapid antigen test devices might have a different respiratory viral infection. We aimed to detect and sequence non-SARS-CoV-2 respiratory viruses from rapid antigen test devices, which could assist in the characterisation and surveillance of circulating respiratory viruses in the community. METHODS:We applied archival clinical nose and throat swabs collected between Jan 1, 2015, and Dec 31, 2022, that previously tested positive for a common respiratory virus (adenovirus, influenza, metapneumovirus, parainfluenza, rhinovirus, respiratory syncytial virus [RSV], or seasonal coronavirus; 132 swabs and 140 viral targets) on PCR to two commercially available COVID-19 rapid antigen test devices, the Panbio COVID-19 Ag Rapid Test Device and Roche SARS-CoV-2 Antigen Self-Test. In addition, we collected 31 COVID-19 rapid antigen test devices used to test patients who were symptomatic at The Royal Melbourne Hospital emergency department in Melbourne, Australia. We extracted total nucleic acid from the device paper test strips and assessed viral recovery using multiplex real-time PCR (rtPCR) and capture-based whole genome sequencing. Sequence and genome data were analysed through custom computational pipelines, including subtyping. FINDINGS:Of the 140 respiratory viral targets from archival samples, 89 (64%) and 88 (63%) were positive on rtPCR for the relevant taxa following extraction from Panbio or Roche rapid antigen test devices, respectively. Recovery was variable across taxa: we detected influenza A in nine of 18 samples from Panbio and seven of 18 from Roche devices; parainfluenza in 11 of 20 samples from Panbio and 12 of 20 from Roche devices; human metapneumovirus in 11 of 16 from Panbio and 14 of 16 from Roche devices; seasonal coronavirus in eight of 19 from Panbio and two of 19 from Roche devices; rhinovirus in 24 of 28 from Panbio and 27 of 28 from Roche devices; influenza B in four of 15 in both devices; and RSV in 16 of 18 in both devices. Of the 31 COVID-19 devices collected from The Royal Melbourne Hospital emergency department, 11 tested positive for a respiratory virus on rtPCR, including one device positive for influenza A virus, one positive for RSV, four positive for rhinovirus, and five positive for SARS-CoV-2. Sequences of target respiratory viruses from archival samples were detected in 55 (98·2%) of 56 samples from Panbio and 48 (85·7%) of 56 from Roche rapid antigen test devices. 98 (87·5%) of 112 viral genomes were completely assembled from these data, enabling subtyping for RSV and influenza viruses. All 11 samples collected from the emergency department had viral sequences detected, with near-complete genomes assembled for influenza A and RSV. INTERPRETATION:Non-SARS-CoV-2 respiratory viruses can be detected and sequenced from COVID-19 rapid antigen devices. Recovery of near full-length viral sequences from these devices provides a valuable opportunity to expand genomic surveillance programmes for public health monitoring of circulating respiratory viruses. FUNDING:Australian Government Medical Research Future Fund and Australian National Health and Medical Research Council.

BackgroundIn Australia the incidence of HIV has declined steadily, yet sustained reduction of HIV transmission in this setting requires improved public health responses. As enhanced public health responses and prioritisation of resources may be guided by molecular epidemiological data, here we aimed to assess the applicability of these approaches in Victoria, Australia.MethodsA comprehensive collection of HIV-1 pol sequences from individuals diagnosed with HIV in Victoria, Australia, between January 1st 2000 and December 31st 2020 were deidentified and used as the basis of our assessment. These sequences were subtyped and surveillance drug resistance mutations (SDRMs) identified, before definition of transmission groups was performed using HIV-TRACE (0.4.4). Phylodynamic methods were applied using BEAST (2.6.6), assessing effective reproductive numbers for large groups, and additional demographic data were integrated to provide a high resolution view of HIV transmission in Victoria on a decadal time scale.FindingsBased on standard settings for HIV-TRACE, 70% (2438/3507) of analysed HIV-1 pol sequences were readily assigned to a transmission group. Individuals in transmission groups were more commonly males (aOR 1.50), those born in Australia (aOR 2.13), those with probable place of acquisition as Victoria (aOR 6.73), and/or those reporting injectable drug use (aOR 2.13). SDRMs were identified in 375 patients (10.7%), with sustained transmission of these limited to a subset of smaller groups. Informative patterns of epidemic growth, stabilisation, and decline were observed; many transmission groups showed effective reproductive numbers (Re) values reaching greater than 4.0, representing considerable epidemic growth, while others maintained low Re values.InterpretationThis study provides a high resolution view of HIV transmission in Victoria, Australia, and highlights the potential of molecular epidemiology to guide and enhance public health responses in this setting. This informs ongoing discussions with community groups on the acceptability and place of molecular epidemiological approaches in Australia.FundingNational Health and Medical Research Council, Australian Research Council.

ObjectivesTo investigate the distribution and prevalence of Japanese encephalitis virus (JEV) antibody (as evidence of past infection) in northern Victoria following the 2022 Japanese encephalitis outbreak, seeking to identify groups of people at particular risk of infection; to investigate the distribution and prevalence of antibodies to two related flaviviruses, Murray Valley encephalitis virus (MVEV) and West Nile virus Kunjin subtype (KUNV).Study designCross-sectional serosurvey (part of a national JEV serosurveillance program).SettingThree northern Victorian local public health units (Ovens Murray, Goulburn Valley, Loddon Mallee), 8 August - 1 December 2022.ParticipantsPeople opportunistically recruited at pathology collection centres and by targeted recruitment through community outreach and advertisements. People vaccinated against or who had been diagnosed with Japanese encephalitis were ineligible for participation, as were those born in countries where JEV is endemic.Main outcome measuresSeroprevalence of JEV IgG antibody, overall and by selected factors of interest (occupations, water body exposure, recreational activities and locations, exposure to animals, protective measures).Results813 participants were recruited (median age, 59 years [interquartile range, 42-69 years]; 496 female [61%]); 27 were JEV IgG-seropositive (3.3%; 95% confidence interval [CI], 2.2-4.8%) (median age, 73 years [interquartile range, 63-78 years]; 13 female [48%]); none were IgM-seropositive. JEV IgG-seropositive participants were identified at all recruitment locations, including those without identified cases of Japanese encephalitis. The only risk factors associated with JEV IgG-seropositivity were age (per year: prevalence odds ratio [POR], 1.07; 95% CI, 1.03-1.10) and exposure to feral pigs (POR, 21; 95% CI, 1.7-190). The seroprevalence of antibody to MVEV was 3.0% (95% CI, 1.9-4.5%; 23 of 760 participants), and of KUNV antibody 3.3% (95% CI, 2.1-4.8%; 25 of 761).ConclusionsPeople living in northern Victoria are vulnerable to future JEV infection, but few risk factors are consistently associated with infection. Additional prevention strategies, including expanding vaccine eligibility, may be required to protect people in this region from Japanese encephalitis.

Antiviral agents with activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have played a critical role in disease management; however, little is known regarding the efficacy of these medications in the treatment of SARS-CoV-2 infection in immunocompromised patients, particularly in the management of persistent SARS-CoV-2 positivity. This narrative review discusses the management of persistent coronavirus disease 2019 in immunocompromised hosts, with a focus on antiviral therapies. We identified 84 cases from the literature describing a variety of approaches, including prolonged antiviral therapy (n = 11), combination antivirals (n = 13), and mixed therapy with antiviral and antibody treatments (n = 60). A high proportion had an underlying haematologic malignancy (n = 67, 80%), and were in receipt of anti-CD20 agents (n = 51, 60%). Success was reported in 70 cases (83%) which varied according to the therapy type. Combination therapies with antivirals may be an effective approach for individuals with persistent SARS-CoV-2 positivity, particularly those that incorporate treatments aimed at increasing neutralizing antibody levels. Any novel approaches taken to this difficult management dilemma should be mindful of the emergence of antiviral resistance.

Coronavirus disease 2019 (COVID-19) in immunocompromised patients can lead to severe and prolonged illness. Data are limited with regard to management of COVID-19 in this setting, particularly in persistent or recrudescent infection. The authors conducted an online survey among infectious diseases doctors to determine current approaches to treatment across Australasia. There was marked variability in responses relating to the diagnostic modalities and use of antiviral agents in patients with immunocompromise, highlighting the need for high-quality studies to guide treatment decisions in this group.

The impact and frequency of infectious disease outbreaks demonstrate the need for timely genomic surveillance to inform public health responses. In the largest known outbreak of mpox, genomic surveillance efforts have primarily focused on high-incidence nations in Europe and the Americas, with a paucity of data from South-East Asia and the Western Pacific. Here we analyzed 102 monkeypox virus (MPXV) genomes sampled from 56 individuals in Melbourne, Australia. All genomes fell within the 2022 MPXV outbreak lineage (B.1), with likely onward local transmission detected. We observed within-host diversity and instances of co-infection, and highlight further examples of structural variation and apolipoprotein B editing complex-driven micro-evolution in the current MPXV outbreak. Updating our understanding of MPXV emergence and diversification will inform public health measures and enable monitoring of the virus' evolutionary trajectory throughout the mpox outbreak.

Over the past decade there have been technical advances in human immunodeficiency virus (HIV) assays and updates to testing regulations that have substantially changed the landscape of laboratory testing for HIV. In addition, there have been significant changes in the epidemiology of HIV in Australia in the context of highly effective contemporary biomedical treatment and prevention strategies. Here, we provide an update on contemporary issues for the laboratory detection and confirmation of HIV in Australia. These include (1) the impact of early treatment and biological prevention strategies on the serological and virological detection of HIV; (2) the updated national HIV laboratory case definition and its interaction with testing regulations, public health and clinical guidelines; and (3) novel strategies for the laboratory detection of HIV, including the incorporation of HIV nucleic acid amplification tests (NAATs) into testing algorithms. These developments present an opportunity to develop a nationally consistent contemporary HIV testing algorithm that would result in optimisation and standardisation of HIV testing in Australia.

There have been significant advances in the prevention and management of Ebola virus disease (EVD) caused by Zaire Ebola virus (ZEBOV), including the development of two effective vaccines, rVSV-ZEBOV and Ad26.ZEBOV/ MVA-BN-Filo. In addition, ZEBOV monoclonal antibodies have become first -line therapy for EVD. However, the 2022-23 outbreak of Sudan Ebola virus (SUDV) in Uganda has highlighted the gap in current therapies and vaccines, whose efficacy is uncertain against non-ZEBOV species. Health-care and laboratory staff working in EVD treatment centres or Ebola virus diagnostic and research laboratories face unique risks relating to potential occupational exposure to Ebola viruses. Given the substantial morbidity and mortality associated with EVD, facilities should have strategies in place to manage occupational exposures, including consideration of post-exposure therapies. In this Review, we discuss currently available evidence for prevention and post-exposure prophylaxis of EVD, including therapies currently under evaluation for SUDV.

The unexpected recent emergence of Japanese encephalitis virus (JEV) genotype IV in multiple southern states of Australia necessitated an evaluation of JEV serological tests suitable for diagnosing acute infection and for seroprevalence studies. This study examined the analytical and clinical performance of two high-throughput JEV assays, Euroimmun immunofluorescence assay (IFA) and Euroimmun enzyme-linked immunosorbent assay (ELISA), across four cohorts; (1) surveillance of piggery workers in outbreak areas, (2) surveillance of residents in outbreak areas, (3) acute JEV infection and (4) post-JEV vaccination. ELISA and IFA IgM demonstrated minimal cross-reactivity (0-1.8%) with other endemic flaviviruses, with high sensitivity (100%) for acute JEV infection in this low endemicity setting. Differences in IgG serodynamics between the two assays suggest convalescent and paired testing with IgM are critical in diagnosing acute infection. High assay concordance was observed between ELISA and IFA when used in serosurveillance (97.4% agreement, Cohen' κ 0.74 [95% CI 0.614-0.860]) and vaccination cohorts (91.1% agreement, Cohen's κ 0.806 [95% CI 0.672-0.941]). In conclusion, this study highlights the clinical & epidemiological applications and limitations of these two commercial JEV assays.

To the Editor, In Australia, diagnosis of human immunodeficiency virus (HIV) infection has traditionally relied on a Western blot (WB) for confirmation. Prior to a recent update to the national laboratory case definition for HIV, laboratory confirmation of HIV diagnosis was fulfilled with a repeatedly reactive HIV antibody or combination antibody/antigen screening test followed by a positive WB, or positive p24 antigen confirmed by neutralisation on two separate specimens.1Public Health Laboratory Network (PHLN)HIV laboratory case definition.2015https://www1.health.gov.au/internet/main/publishing.nsf/Content/F0B1B857E0B579B6CA257FD300072984/$File/HIV2016.pdfGoogle Scholar Although this approach maximises test specificity, it may be limited by prolonged time to HIV-specific IgG development for WB detection and need for repeated specimen collection for p24 assays. The Public Health Laboratory Network (PHLN) updated the HIV laboratory case definition in March 2022 to include nucleic acid amplification tests (NATs) as an alternative confirmatory assay to WB or p24 for HIV diagnosis.2Public Health Laboratory Network (PHLN)HIV laboratory case definition.2022https://www1.health.gov.au/internet/main/publishing.nsf/Content/cda-phlncd-HIV.htmGoogle Scholar The updated laboratory case definition also removed the requirement to collect a second specimen for p24 testing in adults and children aged over 18 months. These changes provide the opportunity for more rapid diagnosis, particularly in acute HIV infection. Here, we sought to assess time to laboratory-confirmed HIV diagnosis using the previous laboratory case definition, comparing time to confirmation using either WB or p24 assay. These results may inform development of an updated diagnostic algorithm to incorporate the recent changes to the national case definition. To assess time to confirmed HIV diagnosis using the previous laboratory case definition, we reviewed cases of newly diagnosed HIV at the Royal Melbourne Hospital from 1 July 2017 to 31 May 2021. Results of the screening HIV immunoassay, WB, p24, HIV viral load and CD4 count were collected. Time to laboratory-confirmed HIV diagnosis was calculated from date of first sample collection for initial HIV testing to the date when case definition for HIV diagnosis was fulfilled. Where available, time from initial sample collection to antiretroviral therapy (ART) commencement was recorded. Differences between individuals diagnosed through WB and p24 assay were compared using Wilcoxon rank-sum using R statistical software (version 4.1.1, https://www.r-project.org/). p values <0.05 were regarded as significant. The study was approved by the Melbourne Health Human Research Ethics Committee as a quality assurance project (QA2021045). Thirty-one cases of HIV were diagnosed during the study period. Twenty-five (81%) fulfilled case definition through positive WB, with median time to laboratory-confirmed HIV diagnosis of 5 days (range 2–10) (Table 1). Six cases with an indeterminate or negative WB fulfilled criteria by p24 assay with median time to confirmed HIV diagnosis of 10 days (range 5–20). Individuals diagnosed through p24 had significantly higher viral loads compared to individuals diagnosed through WB (median 1,273,358 vs 119,002 copies/mL, p=0.008), consistent with acute infection (Fiebig stages II–IV). Individuals diagnosed through WB had established infection: seven (28%) had advanced HIV with CD4 count <0.05×109/L and 12 (48%) with CD4 count <0.20×109/L on presentation. Data on ART commencement were available for 21 of the 31 cases. The 10 individuals with no data available were diagnosed through WB and received follow-up with external primary care providers. For the 21 individuals who commenced ART at our centre, therapy was commenced a median of 10 days post initial sample collection and was the same for individuals diagnosed through WB and p24. Median time to ART commencement for individuals diagnosed through WB with CD4 count <0.05×109/L, <0.20×109/L and ≥0.20 ×109/L was 15, 12 and 9 days, respectively.Table 1Time to new HIV diagnosis, baseline tests and time to antiretroviral therapy commencementAll new HIV diagnoses (n=31)New HIV diagnosis by positive WBaPositive western blot defined as detection of 2 ENV bands (gp160 and/or gp41 and gp120) with GAG (p17, p24, p55) or POL (p31, p51, p66). (n=25)New HIV diagnosis by p24 assay (n=6)p valuebComparison of individuals diagnosed with HIV by WB versus p24 assay using Wilcoxon rank-sum.Days to HIV diagnosiscDiagnosis as per Australian Public Health Laboratory Network 2015.15 (4–8)5 (4–6)10 (9–14)0.004HIV viral load, copies/mL183,888 (101,766–822,415)119,002 (85,704–512,466)1,273,358 (436,986–4,139,515)0.008HIV viral load, log105.26 (5.01–5.92)5.08 (4.93–5.71)6.10 (5.64–6.62)0.001CD4 T cell count, ×109/L0.27 (0.06–0.51)0.16 (0.04–0.34)0.54 (0.51–0.64)0.001CD4 T cell, %16.9 (6.4–24.3)16.0 (4.2–21.5)21.9 (13.8–28.3)0.19Days from sample collection to ART commencement10 (7–18)10 (7–19)10 (8–12)0.99Data are shown as median and interquartile range.ART, antiretroviral therapy; WB, western blot.a Positive western blot defined as detection of 2 ENV bands (gp160 and/or gp41 and gp120) with GAG (p17, p24, p55) or POL (p31, p51, p66).b Comparison of individuals diagnosed with HIV by WB versus p24 assay using Wilcoxon rank-sum.c Diagnosis as per Australian Public Health Laboratory Network 2015.1Public Health Laboratory Network (PHLN)HIV laboratory case definition.2015https://www1.health.gov.au/internet/main/publishing.nsf/Content/F0B1B857E0B579B6CA257FD300072984/$File/HIV2016.pdfGoogle Scholar Open table in a new tab Data are shown as median and interquartile range. ART, antiretroviral therapy; WB, western blot. Our study highlights the limitation of the current diagnostic algorithm in confirming acute HIV infection using the previous case definition, with double the time required to confirm HIV diagnosis in patients with acute compared to established infection. High viral loads observed in acute infection have been associated with transmission risk of up to 26 times higher compared to chronic infection.3Hollingsworth T.D. Anderson R.M. Fraser C. HIV-1 transmission, by stage of infection.J Infect Dis. 2008; 198: 687-693Crossref PubMed Scopus (494) Google Scholar This has led to estimates of disproportionately higher transmission from individuals with acute infection in certain settings; in one study, 35% of new HIV diagnoses among casual sexual partners in men who have sex with men was attributed to transmission from individuals with primary HIV infection.4Xiridou M. Geskus R. de Wit J. et al.Primary HIV infection as source of HIV transmission within steady and casual partnerships among homosexual men.AIDS. 2004; 18: 1311-1320Crossref PubMed Scopus (81) Google Scholar This highlights the importance of timely diagnosis of acute HIV infection in facilitating early counselling, treatment and contact tracing to prevent onward transmission in this group. Although we observed longer time to laboratory-confirmed diagnosis in individuals with acute infection, we did not observe a difference in time to commencement of ART. This may partly be explained by the several cases of advanced HIV in those who were diagnosed through WB, represented by the low median CD4 count in this group of 0.16×109/L. In some of these individuals, ART was necessarily delayed in order to diagnose and manage opportunistic infections, such as cryptococcal meningitis, where ART commencement is deferred for up to 6 weeks after antifungals are started to avoid the immune reconstitution inflammatory syndrome. For individuals without clinical contraindication, ART should be commenced early. Accelerated or same day initiated ART at time of diagnosis has been associated with improved rates of viral suppression and retention in care.5Ford N. Migone C. Calmy A. et al.Benefits and risks of rapid initiation of antiretroviral therapy.AIDS. 2018; 32: 17-23Crossref PubMed Scopus (166) Google Scholar Newer approaches to confirmatory HIV testing have become available that could streamline the diagnostic process, particularly in acute infection. There are now several NATs approved for use by the Therapeutic Goods Administration (TGA) as confirmatory tests for HIV diagnosis in immunoassay-reactive individuals, including the Aptima HIV-1 Quant Dx assay (Hologic, Australia), cobas HIV-1/HIV-2 Qualitative Test (Roche Diagnostics, Australia), cobas HIV-1 assay for use on cobas 6800/8800 systems (Roche Diagnostics), and the Alinity m HIV-1 Kit (Abbott Australasia).6Therapeutic Goods Administration, Australian Department of Health. Australian Register of Therapeutic Goods (ARTG).https://www.tga.gov.au/resources/artgGoogle Scholar These are automated tests and have the advantage of being run either as single tests or in batches to reduce turnaround time. These assays have demonstrated specificity nearing 100% for HIV diagnosis, with a limit of detection of approximately 12–20 copies/mL.7Nair S.V. Kim H.C. Fortunko J. et al.Aptima HIV-1 Quant Dx—a fully automated assay for both diagnosis and quantification of HIV-1.J Clin Virol. 2016; 77: 46-54Crossref PubMed Scopus (29) Google Scholar,8Hans L. Allmen N von Edelmann A. et al.Early diagnosis of HIV-1 and HIV-2 using Cobas HIV-1/HIV-2 qualitative test: a novel qualitative nucleic acid amplification test for plasma, serum, and dried blood spot specimens.J Acquir Immune Defic Syndr. 2021; 87: 1187-1195Crossref PubMed Scopus (6) Google Scholar The specificity of these tests are higher than that of quantitative HIV viral load assays, with several cases of false-positives previously reported using quantitative assays for diagnosis.9Hecht F.M. Busch M.P. Rawal B. et al.Use of laboratory tests and clinical symptoms for identification of primary HIV infection.AIDS. 2002; 16: 1119-1129Crossref PubMed Scopus (217) Google Scholar NATs also have the potential advantage of detecting very early HIV infection, prior to antibody or p24 detection. Using HIV seroconversion panels, HIV-1 could be detected by the Aptima assay 6 days before the p24 antigen,7Nair S.V. Kim H.C. Fortunko J. et al.Aptima HIV-1 Quant Dx—a fully automated assay for both diagnosis and quantification of HIV-1.J Clin Virol. 2016; 77: 46-54Crossref PubMed Scopus (29) Google Scholar and by the cobas assay 19 days earlier than the Bio-Rad Geenius HIV 1/2 Confirmatory Assay.8Hans L. Allmen N von Edelmann A. et al.Early diagnosis of HIV-1 and HIV-2 using Cobas HIV-1/HIV-2 qualitative test: a novel qualitative nucleic acid amplification test for plasma, serum, and dried blood spot specimens.J Acquir Immune Defic Syndr. 2021; 87: 1187-1195Crossref PubMed Scopus (6) Google Scholar One further advantage of the cobas HIV-1/HIV-2 qualitative assay over WB is differentiating HIV-1 and HIV-2, although prevalence of HIV-2 in Australia remains rare. In the United States, NATs are currently only recommended to resolve discrepant results from positive screening immunoassays and negative or indeterminant confirmatory HIV-1/HIV-2 antibody differentiation immunoassay results, as can occur in acute infection. In the United Kingdom, NATs have been listed as an alternative to immunoassays for confirmatory HIV diagnosis, although this is not yet part of standard testing. The cost benefit of this approach has not yet been formally assessed; however, consideration should be given to its potential impact on total testing numbers from reduced indeterminate confirmatory test results, as well as benefits of faster turnaround time, early diagnosis, and reduced transmission. In Australia, the current National Pathology Accreditation Advisory Council (NPAAC) guidelines for laboratory testing of HIV stipulate WB be used for confirmatory testing and that NATs cannot currently be used for laboratory confirmation of HIV.10National Pathology Accreditation Advisory Council (NPAAC) Requirements for Laboratory Testing of Human Immunodeficiency Virus (HIV) and Hepatitis C Virus (HCV).3rd ed. NPAAC, Canberra2013https://www1.health.gov.au/internet/main/publishing.nsf/Content/health-npaac-docs-hivhepc.htmGoogle Scholar The NPAAC guidelines were last updated in 2013 and developed prior to TGA approval of qualitative HIV NATs for diagnosis. In order for clinical laboratories to implement HIV NAT use in HIV diagnosis, these guidelines will require revision to align with the updated PHLN case definition. One limitation when using NATs for confirmatory testing is the potential for false negative results in individuals with undetectable viral load,11Duncan D. Duncan J. Kramer B. et al.An HIV diagnostic testing algorithm using the cobas HIV-1/HIV-2 qualitative assay for HIV type differentiation and confirmation.J Clin Microbiol. 2021; 59030300-20Crossref PubMed Scopus (4) Google Scholar as can occur in elite controllers or individuals on ART that has not been disclosed. This includes individuals who have continued pre-exposure prophylaxis (PrEP) following HIV acquisition, where viral loads have been shown to be lower during seroconversion compared to individuals not on PrEP, with 11% of individuals demonstrating an undetectable viral load.12Donnell D. Ramos E. Celum C. et al.The effect of oral preexposure prophylaxis on the progression of HIV-1 seroconversion.AIDS. 2017; 31: 2007-2016Crossref PubMed Scopus (58) Google Scholar A large study examining the use of HIV NAT as a second-line assay for confirmation of HIV diagnosis was recently conducted by Duncan et al.11Duncan D. Duncan J. Kramer B. et al.An HIV diagnostic testing algorithm using the cobas HIV-1/HIV-2 qualitative assay for HIV type differentiation and confirmation.J Clin Microbiol. 2021; 59030300-20Crossref PubMed Scopus (4) Google Scholar This study described the performance of an alternative diagnostic algorithm using the cobas HIV-1/HIV-2 qualitative NAT as the second-line assay for HIV confirmation compared to the Geenius HIV 1/2 supplemental immunoassay. Negative percent agreements for HIV-1 and HIV-2 was >99% for HIV-1 and HIV-2 for all groups. Positive percent agreement was 100% in the known HIV-1-positive group, however positive percent agreement was lower than expected in a number of groups (58%, 77.7%, 66.7%, for HIV-1 high risk, HIV-2 high risk and HIV low risk populations, respectively). The primary reason for this low positive percent agreement was positive serology results with undetectable HIV RNA. This may have been due to undisclosed ART use such as PrEP, elite controllers as described above, or due to false-positive serology results. This study demonstrates that additional confirmatory testing with traditional methods such as WB, HIV-1/HIV-2 antibody differentiation immunoassay or HIV proviral DNA is likely to be required as a third test in a HIV NAT-based algorithm for fourth-generation immunoassay screen-positive/NAT-negative specimens. The updated national case definition now provides opportunity for NATs to be incorporated into the HIV diagnostic algorithm, however the implementation of significant changes to HIV testing by laboratories is currently limited by discordant NPAAC standards. Incorporation of these newer tests into a HIV diagnostic algorithm could significantly reduce time to confirmation of HIV diagnosis while importantly retaining high test specificity. The authors state that there are no conflicts of interest to disclose.

PURPOSE OF REVIEW:This review provides an update on recent findings about the clinical and microbiological characteristics of Staphylococcus lugdunensis .RECENT FINDINGS:European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) differ in their methodology and breakpoints for the detection of penicillin and oxacillin resistance in S. lugdunensis . The EUCAST method for beta-lactamase detection recommends a 1-unit penicillin disk and has demonstrated superior performance compared to the 10-unit penicillin disk recommended by CLSI. A similar outcome has been previously reported in Staphylococcus aureus. In addition, there is emerging oxacillin resistance in some geographical areas. Of particular concern is that oxacillin resistance in mecA positive isolates may not be reliably detected by current cefoxitin breakpoints.SUMMARY:Coagulase negative staphylococci are now recognised as a heterogenous group of organisms that do not microbiologically or clinically behave the same way. The spectrum of clinical disease is species dependent and is particularly true for S. lugdunensis , which causes an array of clinical infections like that of S. aureus. Further studies are needed to assess the performance of phenotypic tests to detect resistance, to ensure that appropriate antimicrobial therapy is delivered to patients.

Abstract Background Current guidelines recommend empiric antibiotics be used only for severe cases of coronavirus disease 2019 (COVID-19) or in cases where there is high clinical suspicion for bacterial co-infection. Level of adherence to guideline-recommended prescribing is unknown and high rates of antimicrobial prescribing may lead to increased development of resistance. Methods We reviewed antimicrobial prescribing patterns for patients with COVID-19 managed at The Alfred Hospital in Melbourne, Australia in 2020. Adherence to World Health Organization (WHO) guideline-based prescribing was assessed by manual review of case notes. Monthly hospital-wide antibacterial consumption April-Dec 2020 (post-pandemic period) was compared to Jan 2019-Mar 2020 (pre-pandemic period), measured as days of therapy (DOT) per 1000 patient-days. Rates of multi-drug resistant organisms (MRO) (including MRSA, VRE, CPE, ESBL) were compared between months in 2019 and 2020 after pandemic onset (April 2020) and expressed as isolates per 1000 patient-days. Results 147 patients were managed for COVID-19 in 2020 at our centre. 101 patients required hospital admission and 58 (39%) were classified as either severe or critical in severity. 80 (54%) patients received empiric antimicrobial treatment, including 78/101 (77%) of hospital inpatients and 24/26 (92%) of ICU-admitted patients. 59 (73%) of antimicrobial prescriptions were adherent to WHO guidelines. Monthly antibacterial consumption was significantly lower post-pandemic than in the pre-pandemic period (mean 853 vs 902 DOT/1000 patient-days, P=0.0065). Antimicrobial use patterns varied, with significant decreases in commonly used antibiotics such as ceftriaxone, piperacillin-tazobactam, azithromycin and ciprofloxacin but no change in vancomycin or meropenem (Figure 1). There was a mean decrease of 0.77 MRO isolates/1000 patient-days (P=0.026) when each month in 2020 was compared with the corresponding month in 2019 (Figure 2). Antibacterial consumption in 2019 and 2020 by month, expressed as days of therapy/1000 patient-days. Rates of isolated multi-drug resistant organisms in 2019 and 2020 by month, expressed as isolates/1000 patient-days. Conclusion A high proportion of admitted patients with COVID-19 received empiric antibiotics. In spite of this, we observed a significant reduction in total antimicrobial consumption and reduced rates of MRO isolation in the post-pandemic period. Disclosures All Authors: No reported disclosures

To the Editor—The rapid global dissemination of carbapenem-resistant Enterobacterales (CRE) and vancomycinresistant Enterococcus (VRE) presents a major clinical challenge [1]. Treatment options for these organisms are limited, and there are few data regarding peritoneal dialysis (PD)-related intraabdominal infections [2, 3]. Thus, we wish to share our recent experience in managing a patient with polymicrobial PD-related peritonitis involving NewDelhi metallo-beta-lactamase-1 (NDM1)-producing Klebsiella pneumoniae and vanB VRE treated successfully with intravenous (IV) tigecycline. A 69-year-old man recently commenced PD for end-stage renal failure secondary to antiglomerular basement membrane (anti-GBM) disease. His medical history was significant for previous autologous stem cell transplant for multiple myeloma and ischemic heart disease. He was initially admitted for management of thrombotic microangiopathy (TMA) complicating his anti-GBM disease, requiring immunosuppression with IV methylprednisolone, rituximab, and plasma exchange. One week into admission, the patient developed severe abdominal pain with guarding. The peritoneal effluent was cloudy; however, he remained afebrile and the Tenckhoff catheter site was not infected. White cell count was 4.75 × 10/L and C-reactive protein was raised at 192 mg/L. The peritoneal fluid demonstrated an elevated polymorph count of 9260 × 10/L, and Gram-positive cocci (GPC) were noted on microscopy. A computed tomography scan of the abdomen demonstrated no evidence of bowel perforation or colitis. The patient was commenced on intraperitoneal (IP) cefazolin and received a single dose of IP gentamicin 0.6 mg/kg on day 1, as per institutional guidelines. An initial loading dose of 20 mg/kg IP cefazolin was given and continued at 125 mg/L per exchange until removal of the Tenckhoff catheter. A single dose of IP vancomycin 30 mg/kg was administered on the second day. Blood cultures returned positive for Gram-negative bacilli and IV piperacillin/tazobactam 4.5 g q8h was commenced. Serial sampling of peritoneal fluid demonstrated down-trending polymorph count; however, Gram-stain demonstrated persistence of GPC in peritoneal fluid at day 4. The initial peritoneal fluid cultures returned positive for K pneumoniae, Enterococcus faecalis, Escherichia coli, and mixed anaerobes with susceptibilities outlined in Table 1. The blood culture returned positive for Bacteroides species. Peritoneal cultures from the second and third day grew E faecium and Candida albicans. The Tenckhoff catheter was removed due to ongoing positivity of peritoneal applyparastyle “fig//caption/p[1]” parastyle “FigCapt”

Disseminated histoplasmosis (DH), an endemic mycosis caused by the dimorphic fungus Histoplasma capsulatum, is a life-threatening infection in immunocompromised hosts. A patient with newly-diagnosed human immunodeficiency virus (HIV) infection presented with a violaceous, raised, indurated, pruritic rash over the face, arms and trunk on a background of significant weight loss, fevers with sweats, diarrhoea and worsening shortness of breath. His CD4+ T cell count was 14 cells/µl (12%). Histoplasmosis was diagnosed from histology, fungal stain and culture of skin biopsy. In addition to DH, he was found to have Pneumocystis jiroveci pneumonia and multi-resistant Salmonella choleraesuis bacteraemia. He improved with treatment with antibiotics and was commenced on conventional itraconazole, orally. Antiretroviral therapy was commenced soon after. He was unable to achieve therapeutic levels with the conventional formulation due to gastrointestinal side effects and had ongoing fevers. A newer formulation of oral itraconazole with improved bioavailability was commenced. He achieved therapeutic drug levels and had no further intolerance. His fevers settled and the rash improved. He has now completed one year of treatment and is well. To our knowledge this is the first case of moderate DH in an advanced HIV patient treated successfully with oral itraconazole with improved bioavailability.

Objective: To determine whether latency can be established and reversed in both proliferating and nonproliferating CD4+ T cells in the same model in vitro. Methods: Activated CD4+ T cells were infected with either a nonreplication competent, luciferase reporter virus or wild-type full-length enhanced green fluorescent protein (EGFP) reporter virus and cultured for 12 days. The cells were then sorted by flow cytometry to obtain two distinct T-cell populations that did not express the T-cell activation markers, CD69, CD25 and human leukocyte antigen (HLA)-DR: CD69−CD25−HLA-DR− small cells (nonblasts) that had not proliferated in vitro following mitogen stimulation and CD69−CD25−HLA-DR− large cells (which we here call transitional blasts) that had proliferated. The cells were then reactivated with latency-reversing agents and either luciferase or EGFP quantified. Results: Inducible luciferase expression, consistent with latent infection, was observed in nonblasts and transitional blasts following stimulation with either phorbol-myristate-acetate/phytohemagglutinin (3.8 ± 1 and 2.9 ± 0.5 fold above dimethyl sulfoxide, respectively) or romidepsin (2.1 ± 0.6 and 1.8 ± 0.2 fold above dimethyl sulfoxide, respectively). Constitutive expression of luciferase was higher in transitional blasts compared with nonblasts. Using wild-type full-length EGFP reporter virus, inducible virus was observed in nonblasts but not in transitional blasts. No significant difference was observed in the response to latency-reversing agents in either nonblasts or transitional blasts. Conclusion: HIV latency can be established in vitro in resting T cells that have not proliferated (nonblasts) and blasts that have proliferated (transitional blasts). This model could potentially be used to assess new strategies to eliminate latency.

Objective:The current study aimed to validate existing risk prediction scores and identify predictors of chronic kidney disease (CKD) in the setting of HIV.Design and methods:A retrospective cohort study of HIV-positive individuals (n=748) with baseline estimated glomerular filtration rate (eGFR) more than 60ml/min was conducted at the Alfred Hospital, Melbourne, Australia. Multivariable regression analysis was performed to determine factors associated with development of CKD, defined as two consecutive measurements of eGFR less than 60ml/min. The performance of CKD risk scores proposed by the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) Study Group and Scherzer and colleagues were estimated by the area under the receiver operator curve (AUROC).Results:CKD developed in 37 individuals (5.0%), at a median of 4.7 (interquartile range 2.2, 6.2) years. Older age [odds ratio (OR) 3.03, 95% confidence interval (CI): 1.20, 7.65, P=0.02] and lower baseline eGFR (OR 10.39, 95% CI: 4.73, 22.83, P<0.001) were associated with the development of CKD. Neither current, nor cumulative tenofovir disoproxil fumarate (TDF) use was associated with progression to CKD [current TDF hazard ratio (HR) 1.05, 95% CI: 0.54, 2.07, P=0.88; cumulative TDF HR 1.03, 95% CI: 0.86, 1.24, P=0.75]. The short D:A:D and Scherzer scores were well calibrated, with the short D:A:D score demonstrating superior discrimination (short D:A:D AUROC 0.85, Scherzer AUROC 0.78, P=0.02).Conclusion:Older individuals and those with a lower baseline eGFR are at higher risk for CKD. Risk prediction tools may be useful in identifying those at greatest risk, who may benefit from aggressive management of risk factors.

Despite the success of combination antiretroviral therapy (cART), HIV persists in long lived latently infected cells in the blood and tissue, and treatment is required lifelong. Recent clinical studies have trialed latency-reversing agents (LRA) as a method to eliminate latently infected cells; however, the effects of LRA on the central nervous system (CNS), a well-known site of virus persistence on cART, are unknown. In this study, we evaluated the toxicity and potency of a panel of commonly used and well-known LRA (panobinostat, romidepsin, vorinostat, chaetocin, disulfiram, hexamethylene bisacetamide [HMBA], and JQ-1) in primary fetal astrocytes (PFA) as well as monocyte-derived macrophages as a cellular model for brain perivascular macrophages. We show that most LRA are non-toxic in these cells at therapeutic concentrations. Additionally, romidepsin, JQ-1, and panobinostat were the most potent at inducing viral transcription, with greater magnitude observed in PFA. In contrast, vorinostat, chaetocin, disulfiram, and HMBA all demonstrated little or no induction of viral transcription. Together, these data suggest that some LRA could potentially activate transcription in latently infected cells in the CNS. We recommend that future trials of LRA also examine the effects of these agents on the CNS via examination of cerebrospinal fluid.