Bacterial genomics is increasingly used for infectious diseases surveillance, outbreak detection and prediction of antibiotic resistance. With expanding availability of rapid whole-genome sequencing, bacterial genomics data could become a valuable tool for clinicians managing bacterial infections, driving precision medicine strategies. Here, we present a clinician-driven bacterial genomics framework that applies within-patient evolutionary analysis to identify in real-time microbial genetic changes that have an impact on treatment outcomes of severe Staphylococcus aureus infections, a strategy that is increasingly used in cancer genomics. Our approach uses a combination of bacterial genomics and antibiotic susceptibility testing to identify and track bacterial adaptive mutations that underlie microbiologically documented treatment failure (i.e. ongoing positive cultures [persistent infection] or new positive cultures after initial response [recurrent infection]). We show the potential added value of our approach to clinicians and propose a roadmap for the use of bacterial genomics to advance the management of severe bacterial infections.

We aim to define the optimal white cell count threshold that correlates with a clinically significant urinary tract infection, as there is insufficient data exploring this in the adult population. We conducted a retrospective cohort study at the Royal Melbourne Hospital analyzing urine samples collected over 6 months in 2022. Urinary tract infection (UTI) was defined as the presence of symptoms (dysuria, urgency, frequency, flank pain, or loin to groin pain) and isolation of a uropathogen with colony counts greater than 107 CFU/L. The relationship between urinary white cell count, growth of uropathogen, and likelihood of UTI was estimated using locally weighted scatterplot smoothing. Of the 6,328 samples included, at a urinary white cell count of less than 10 per microliter, 38% grew a microorganism, while 7% of the total grew a uropathogen. For our sub-analysis part C, at the same WBC count, 2% of samples fulfilled our criteria for UTI. The optimal WBC range for identifying a UTI was 30-50 WBC/µL, demonstrating the most pragmatic balance of sensitivity (92.3%-94.9%, 95% CI 85.9-98.1) and specificity (41.6-47.2, 95% CI 38.6%-50.3%) for a UTI. A lower-than-expected number of UTIs were confirmed in our study, likely due to inappropriate indications for culture collection and the types of urine specimens collected. However, the optimal white cell cutoff for identifying a UTI was higher than the defined pyuria cutoff of 10 WBC/µL. Utilizing a higher urinary WBC cutoff could improve urine culture processing protocols. IMPORTANCE:The importance of this study is that it explores the optimal range of white cell count that defines a clinically significant urinary tract infection. The traditional cutoff of more than 10 white blood cells per microliter is often used; however, we now recognize that using this cutoff may not accurately represent true urinary infections, especially in certain populations such as young women. The uncertainty in the optimal white cell count cutoff has widespread implications. For the clinician, it may lead to unnecessary prescribing of antibiotics for patients who do not have a Urinary tract infection, such as asymptomatic bacteriuria. For the microbiology laboratory, it may lead to unnecessary workup and culture of urine samples that are not clinically relevant. Many studies to date have attempted to define an optimal value for urinary white cell count; however, not many have incorporated relevant clinical data, which this study has.

Introduction Substantial population-level variation in vaccine-specific antibody responses has been observed following global coronavirus disease 2019 (COVID-19) vaccination efforts. Beyond the influence of clinical and demographic features, immunogenetic variation is suggested to underlie divergent serological responses following COVID-19 vaccination of distinct populations. Methods Immunoglobulin G1 (IgG1) allotypic markers (G1m) for 121 COVID-19 vaccinated healthy adults were genotyped via Sanger sequencing. Vaccine-specific IgG and Fc gamma receptor (FcγR) engagement were characterised via bead-based multiplex array. Results Following two COVID-19 vaccine doses, G1m1,17+/+ compared to G1m-1,3+/+ vaccinees had increased IgG and FcγR engagement specific for the antigenically conserved SARS-CoV-2 Spike 2 (S2) domain. IgG targeting antigenically novel SARS-CoV-2 receptor binding domain (RBD) trended higher in G1m1,17+/+ vaccinees, facilitating increased RBD-specific FcγR2a-R131 and FcγR2b binding. Conclusion Primary COVID-19 vaccination induced increased S2-specific IgG in G1m1,17+/+ vaccinees, facilitating enhanced anti-viral FcγR engagement and suggesting immunogenetics may be a valuble consideration for next-generation vaccine design.

OBJECTIVES:Whole genome sequencing (WGS) can identify clusters, transmission patterns, and drug resistance mutations. This is important in low-burden settings such as Australia, as it can assist in efficient contact tracing and surveillance.METHODS:We conducted a retrospective cohort study using WGS from 155 genomically defined drug-resistant Mycobacterium tuberculosis (DR-TB) isolates collected between 2018-2021 in Victoria, Australia. Bioinformatic analysis was performed to identify resistance-conferring mutations, lineages, clusters and understand how local sequences compared with international context.RESULTS:Of the 155 sequences, 42% were identified as lineage 2 and 35% as lineage 1; 65.8% (102/155) were isoniazid mono-resistant, 8.4% were multi-drug resistant TB and 5.8% were pre-extensively drug-resistant / extensively drug-resistant TB. The most common mutations were observed in katG and fabG1 genes, especially at Ser315Thr and fabG1 -15 C>T for first-line drugs. Ser450Leu was the most frequent mutation in rpoB gene. Phylogenetic analysis confirmed that Victorian DR-TB were associated with importation events. There was little evidence of local transmission with only five isolate pairs.CONCLUSION:Isoniazid-resistant TB is the commonest DR-TB in Victoria, and the mutation profile is similar to global circulating DR-TB. Most cases are diagnosed among migrants with limited transmission. This study highlights the value of WGS in identification of clusters and resistance-conferring mutations. This information is crucial in supporting disease mitigation and treatment strategies.

Abstract Objectives Amino acid variations across more than 30 immunoglobulin (Ig) allotypes may introduce structural changes that influence recognition by anti‐Ig detection reagents, consequently confounding interpretation of antibody responses, particularly in genetically diverse cohorts. Here, we assessed a panel of commercial monoclonal anti‐IgG1 clones for capacity to universally recognise two dominant IgG1 haplotypes (G1m‐1,3 and G1m1,17). Methods Four commercial monoclonal anti‐human IgG1 clones were assessed via ELISAs and multiplex bead‐based assays for their ability to bind G1m‐1,3 and G1m1,17 IgG1 variants. Detection antibodies were validated against monoclonal IgG1 allotype standards and tested for capacity to recognise antigen‐specific plasma IgG1 from G1m‐1,3 and G1m1,17 homozygous and heterozygous SARS‐CoV‐2 BNT162b2 vaccinated (n = 28) and COVID‐19 convalescent (n = 44) individuals. An Fc‐specific pan‐IgG detection antibody corroborated differences between hinge‐ and Fc‐specific anti‐IgG1 responses. Results Hinge‐specific anti‐IgG1 clone 4E3 preferentially bound G1m1,17 compared to G1m‐1,3 IgG1. Consequently, SARS‐CoV‐2 Spike‐specific IgG1 levels detected in G1m1,17/G1m1,17 BNT162b2 vaccinees appeared 9‐ to 17‐fold higher than in G1m‐1,3/G1m‐1,3 vaccinees. Fc‐specific IgG1 and pan‐IgG detection antibodies equivalently bound G1m‐1,3 and G1m1,17 IgG1 variants, and detected comparable Spike‐specific IgG1 levels between haplotypes. IgG1 responses against other human coronaviruses and influenza were similarly poorly detected by 4E3 anti‐IgG1 in G1m‐1,3/G1m‐1,3 subjects. Conclusion Anti‐IgG1 clone 4E3 confounds assessment of antibody responses in clinical cohorts owing to bias towards detection of G1m1,17 IgG1 variants. Validation of anti‐Ig clones should include evaluation of binding to relevant antibody variants, particularly as the role of immunogenetics upon humoral immunity is increasingly explored in diverse populations.

Outcomes are presented for a multisite retrospective case series, describing a contemporary cohort of 22 immunocompromised patients with persistent coronavirus disease 2019 (COVID-19) polymerase chain reaction positivity who were retreated with antiviral therapy. For those with data available 14 and 30 days after commencement of antiviral therapy, 41% (9 of 22) and 68% (15 of 22), respectively, cleared COVID-19.

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Background and objective Ongoing symptoms of COVID-19 can persist for weeks or months after the initial COVID-19 infection. The aim of this study was to identify persistent symptoms (fatigue, cognition, quality of life, anxiety, depression and physical measures) in unvaccinated community -managed patients following COVID-19 infection. Methods This was a prospective nested observational study of health and wellbeing measures determined seven and 13 months after COVID-19 infection, alongside physical abilities after 18 months. Results Data analyses were completed on 62 participants (60% female, median age 35 years). Severe fatigue was noted in 47% of participants at seven months and this had not improved significantly by 13 months (45%). Quality of life and mental health scores were significantly worse in individuals with severe fatigue. One -quarter of participants demonstrated mild cognitive impairment at seven months. After 18 months, walking and lung function were normal, but grip strength was reduced in 26% of participants. Discussion A significant proportion of unvaccinated COVID-19 patients had not returned to pre -illness levels of health and function after one year; screening functional ability and mental wellbeing is warranted in unvaccinated people with COVID-19.

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.

Objective: Clostridioides difficile infection (CDI) is the commonest cause of healthcare-associated diarrhea and undergoes standardized surveillance and mandatory reporting in most Australian states and territories. Historically attributed to nosocomial spread, local and international whole genome sequencing (WGS) data suggest varied sources of acquisition. This study describes C. difficile genotypes isolated at a tertiary center in Melbourne, Australia, their likely source of acquisition, and common risk factors. Design: Retrospective observational study. Setting: The Royal Melbourne Hospital (RMH), a 570-bed tertiary center in Victoria, Australia. Methods: Short-read whole genome sequencing was performed on 75 out of 137 C. difficile isolates obtained from 1/5/2021 to 28/2/2022 and compared to previous data from 8/11/2015 to 1/11/2016. Existing data from infection control surveillance and electronic medical records were used for epidemiological and risk factor analysis. Results: Eighty-five (62.1%) of the 137 cases were defined as healthcare-associated from epidemiological data. On genome sequencing, 33 different multi-locus sequence type (MLST) subtypes were identified, with changes in population structure compared to the 2015-16 period. Risk factors for CDI were present in 130 (94.9%) cases, including 108 (78.8%) on antibiotics, 86 (62.8%) on acid suppression therapy, and 25 (18.2) on chemotherapy. Conclusion: In both study periods, most C. difficile isolates were not closely related, suggesting varied sources of acquisition and that spread of C. difficile within the hospital was unlikely. Current infection control precautions may therefore warrant review. Underlying risk factors for CDI were common and may contribute to the proportion of healthcare-associated infections in the absence of proven hospital transmission.

Background Whole genome sequencing shows promise to improve the clinical management of tuberculosis, but bioinformatic tools tailored for clinical reporting and suitable for accreditation to ISO standards are currently lacking. Methods We developed tbtAMR, a comprehensive pipeline for analysis of Mycobacterium tuberculosis genomic data, including inference of phenotypic susceptibility and lineage calling from both solid and broth (MGIT) cultures. We used local and publicly-availably real-world data (phenotype and genotype) and synthetic genomic data to determine the appropriate quality control metrics and extensively validate the pipeline for clinical use. We combined and curated the large global databases of resistance mutations, fine-tuned for clinical purposes, by minimising false-positives whilst maintaining accuracy. Findings tbtAMR accurately predicted lineages and phenotypic susceptibility for first- and second-line drugs, including from broth (MGIT) cultures. We designed and implemented a reporting template suitable for clinical and public health users and accredited the pipeline to ISO standards. Interpretation The tbtAMR pipeline is accurate and fit-for-purpose for clinical and public health uses. Report templates, validation methods and datasets are provided here to offer a pathway for laboratories to adopt and seek their own accreditation for this critical test, to improve the management of tuberculosis globally. Funding No specific funding was received for this study.

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.

Pregnancy poses a greater risk for severe COVID-19; however, underlying immunological changes associated with SARS-CoV-2 during pregnancy are poorly understood. We defined immune responses to SARS-CoV-2 in unvaccinated pregnant and nonpregnant women with acute and convalescent COVID-19, quantifying 217 immunological parameters. Humoral responses to SARS-CoV-2 were similar in pregnant and nonpregnant women, although our systems serology approach revealed distinct antibody and FcγR profiles between pregnant and nonpregnant women. Cellular analyses demonstrated marked differences in NK cell and unconventional T cell activation dynamics in pregnant women. Healthy pregnant women displayed preactivated NK cells and γδ T cells when compared with healthy nonpregnant women, which remained unchanged during acute and convalescent COVID-19. Conversely, nonpregnant women had prototypical activation of NK and γδ T cells. Activation of CD4+ and CD8+ T cells and T follicular helper cells was similar in SARS-CoV-2–infected pregnant and nonpregnant women, while antibody-secreting B cells were increased in pregnant women during acute COVID-19. Elevated levels of IL-8, IL-10, and IL-18 were found in pregnant women in their healthy state, and these cytokine levels remained elevated during acute and convalescent COVID-19. Collectively, we demonstrate perturbations in NK cell and γδ T cell activation in unvaccinated pregnant women with COVID-19, which may impact disease progression and severity during pregnancy.

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.

Immunocompromised hematology patients are vulnerable to severe COVID-19 and respond poorly to vacci-nation. Relative deficits in immunity are, however, unclear, especially after 3 vaccine doses. We evaluated immune responses in hematology patients across three COVID-19 vaccination doses. Seropositivity was low after a first dose of BNT162b2 and ChAdOx1 (-26%), increased to 59%-75% after a second dose, and increased to 85% after a third dose. While prototypical antibody-secreting cells (ASCs) and T follicular helper (Tfh) cell responses were elicited in healthy participants, hematology patients showed prolonged ASCs and skewed Tfh2/17 responses. Importantly, vaccine-induced expansions of spike-specific and pep-tide-HLA tetramer-specific CD4+/CD8+ T cells, together with their T cell receptor (TCR) repertoires, were robust in hematology patients, irrespective of B cell numbers, and comparable to healthy participants. Vacci-nated patients with breakthrough infections developed higher antibody responses, while T cell responses were comparable to healthy groups. COVID-19 vaccination induces robust T cell immunity in hematology patients of varying diseases and treatments irrespective of B cell numbers and antibody response.

The public health utility of whole genome sequencing (WGS) for Mycobacterium tuberculosis includes genome-wide mutation analysis for genotypic drug susceptibility testing (DST), strain identification, differentiation of tuberculosis (TB) relapse from re-infection, transmission cluster detection to guide targeted public health responses and detection of laboratory cross contamination. This has the potential to optimise individual patient care and provide better targeted TB control measures compared to previous MIRU-VNTR genotyping methods. High resolution genotyping of TB should allow better targeting of contact tracing interventions and prevention strategies. WGS will be useful in programmatic evaluation of clinical and public health TB programs through the identification of relapse and cluster analyses to assess effectiveness of contact tracing activities. Characterising pathogens using WGS is usually less laborious and less expensive than traditional typing methods, and laboratory costs will likely further decrease as it is probable that WGS will soon reduce the need for routine phenotypic DST. However, resource, infrastructure and workforce (including information technology infrastructure and bioinformatics support) has limited implementation of WGS in some jurisdictions, though all mycobacterial reference laboratories in Australia have implemented WGS to some extent. Pathogen genomic data need to be integrated with clinical and public health data to realise their full value. Effective reporting strategies still need to be established, including analyses of key clinical variables and reporting of clusters over time, as well as processes for communicating clusters in a timely manner for public health benefit. NTAC and CDGN consider it a future requirement for all jurisdictions to have: center dot access to prospective WGS of TB isolates; center dot WGS results incorporated into routine laboratory reporting systems; center dot WGS results reported to clinicians and public health programs; center dot WGS results integrated into the routine TB surveillance system; center dot routine cross jurisdictional comparison of WGS data; and center dot continued education for public health staff and clinicians. Through increasing capacity for identification of transmission risk and opportunities to intervene and prevent reactivation, WGS will be an increasingly valuable tool for TB control and elimination in Australia.

ABSTRACTHumans commonly have low level antibodies to poly(ethylene) glycol (PEG) due to environmental exposure. Lipid nanoparticle (LNP) mRNA vaccines for SARS-CoV-2 contain small amounts of PEG but it is not known whether PEG antibodies are enhanced by vaccination and what their impact is on particle–immune cell interactions in human blood. We studied plasma from 130 adults receiving either the BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) mRNA vaccines, or no SARS-CoV-2 vaccine for PEG-specific antibodies. Anti-PEG IgG was commonly detected prior to vaccination and was significantly boosted a mean of 13.1-fold (range 1.0 to 70.9) following mRNA-1273 vaccination and a mean of 1.78-fold (range 0.68 to 16.6) following BNT162b2 vaccination. Anti-PEG IgM increased 68.5-fold (range 0.9 to 377.1) and 2.64-fold (0.76 to 12.84) following mRNA-1273 and BNT162b2 vaccination, respectively. The rise in PEG-specific antibodies following mRNA-1273 vaccination was associated with a significant increase in the association of clinically relevant PEGylated LNPs with blood phagocytes ex vivo. PEG antibodies did not impact the SARS-CoV-2 specific neutralizing antibody response to vaccination. However, the elevated levels of vaccine-induced anti-PEG antibodies correlated with increased systemic reactogenicity following two doses of vaccination. We conclude that PEG-specific antibodies can be boosted by LNP mRNA-vaccination and that the rise in PEG-specific antibodies is associated with systemic reactogenicity and an increase of PEG particle–leukocyte association in human blood. The longer-term clinical impact of the increase in PEG-specific antibodies induced by lipid nanoparticle mRNA-vaccines should be monitored.

ABSTRACTBACKGROUND AND AIMSVaccine-mediated immune responses in patients with inflammatory bowel disease (IBD) may be influenced by IBD therapies. We investigated in-depth humoral and T-cell responses to SARS-CoV-2 vaccination in IBD patients following three COVID-19 vaccine doses.METHODSImmune responses of 100 SARS-CoV-2-uninfected IBD patients on varying treatments were compared to healthy controls (n=35). Anti-S1/2 and anti-RBD SARS-CoV-2-specific antibodies, CD4+and CD8+T-cell responses were measured at baseline and at five time-points after COVID-19 vaccination.RESULTSAnti-S1/2 and anti-RBD antibody concentrations at ∼1 month after second dose vaccination were significantly lower in anti-TNF-treated patients compared to non-TNF IBD patients and healthy controls (126.4 vs 262.1 and 295.5, p<0.0001). Anti-S1/2 antibodies remained reduced in anti-TNF treated patients before and after the third dose (285.7 vs 365.3,p=0.03), although anti-RBD antibodies reached comparable titres to non-TNF patients. Anti-RBD antibodies were higher in the vedolizumab group than controls after second dose (4.2 vs 3.6, p=0.003). Anti-TNF monotherapy was associated with increased CD4+and CD8+T-cell activation compared to combination anti-TNF patients after second dose, but comparable after third dose. Overall, IBD patients demonstrated similar CD4+/CD8+T-cell responses compared to healthy controls regardless of treatment regimen.CONCLUSIONSAnti-TNFs impaired antibody concentrations when compared to non-TNF patients and controls after two vaccine doses. These differences were not observed after the third vaccine dose. However, vaccine induced SARS-CoV-2-specific T cell responses are robust in anti-TNF-treated patients. Our study supports the need for timely booster vaccination particularly in anti-TNF treated patients to minimise the risk of severe SARS-CoV-2 infection.

Abstract Background The characteristics of SARS-CoV-2 vaccine-induced immunity in inflammatory bowel disease (IBD) patients on immune modifying agents has not been clearly defined due to their exclusion in vaccine trials. Emerging results suggest infliximab impairs antibody response compared to vedolizumab. However there has not been direct comparison to controls. We evaluated this with both humoral and T cell response in IBD patients. Methods Antibody and T cell response were analysed in IBD patients who received BNT162b2 (Pfizer–BioNTech) or ChAdOx1 nCoV-19 (Oxford–AstraZeneca) vaccination from a single Australian centre. The control group were healthcare workers (HCW) without IBD. Blood samples were taken at 4 time points: at baseline V0 (before vaccination); V1 (7–14 days after vaccine 1); V2 (7–14 days after vaccine 2); V3 (21–42 days after vaccine 2). Antibodies to the S1/2 IgG subunit and receptor-binding protein (RBD) were measured and reported here. Results 88 (28 ulcerative colitis, 50 Crohn’s disease) IBD patients were included and compared to 53 healthy controls (Table 1). IBD patients medications included 6 5ASA (6.8%), 6 immunomodulator monotherapy (6.8%), 14 anti-TNF monotherapy (15.9%), 32 anti-TNF combination therapy with immunomodulator (36%), 16 IL12/23 (18%) and 13 vedolizumab (14%). Pre-vaccine baseline sera showed absence of anti-RBD antibodies in all participants. 84 patients (87%) received BNT162b2 and 4 (4.5%) received ChAdOx1 nCoV-19 vaccines. Geometric mean [SD] anti-S1/2 antibody concentrations at 4 weeks after second vaccination (V3) were significantly lower in IBD TNF treated patients (162.6[1.7]) compared to IBD non TNF treated patients (325.2[1.3]), and healthy controls (325.2[1.3]), p<0.0001 (Figure 1). There was no difference between non-TNF treated patients including those on vedolizumab or IL12/23 compared to controls. Similarly there was a significant difference between anti-RBD IgG titres between TNF and non-TNF IBD patients at V3 but not when compared to controls (Figure 2). There was no difference in RBD IgG and anti-S1/2 antibodies between anti-TNF monotherapy and combination anti-TNF with immunomodulator. All IBD and healthy controls seroconverted at V3 (Figure 3). Conclusion TNF agents influence SARS-CoV-2 vaccine-induced antibody response in IBD patients, with lower anti-S1/2 IgG concentrations compared to non-TNF IBD patients and healthy controls. However, there was no difference in RBD IgG titres between controls and IBD patients overall. It is unclear whether these subtle differences in antibody response in IBD patients on TNF agents is biologically meaningful, as all groups seroconverted after second dose vaccination. Neutralising antibody and T cell data (CD4+/CD8+) from this study to come.