Use of cigarettes and e-cigarettes, impulsivity and anxiety: Influences on suicidal ideation among youth and young adults in Texas.

INTRODUCTION: Cigarette use and smoking intensity increase risk of suicidal ideation. Less is known about e-cigarette use. Here we examine direct influences of cigarette versus e-cigarette use on suicidal ideation among 16-to-23-year-olds in Texas. METHODS: Since 2019 the Texas Adolescent Tobacco and Marketing Surveillance study collected data on suicidal ideation every six months covering the previous two-weeks. Youths answering that they had "thoughts that you would be better off dead, or of hurting yourself" on more than two of 14 days were categorized as having suicidal ideation. Generalized linear mixed-effects logistic regressions examined the influence of ever and past 30-day (P30D) use of cigarettes, e-cigarettes, impulsivity and anxiety on suicidal ideation, controlling for gender, race/ethnicity, SES, and grade in school. Interactions between ever and P30D use of both products and a) impulsivity and b) gender were examined. RESULTS: Of the 2,329 participants, 29.1% reported ever and 6.5% reported P30D cigarette use, 48.2% reported ever and 11.6% reported P30D e-cigarette use, and 18.5% reported suicidal ideation. Ever cigarette use among females (aOR=1.83; 95% CI: 1.36-2.46), P30D e-cigarette use (aOR=1.30; 95% CI: 1.00-1.68), and P30D cigarette use (aOR=1.47; 95% CI: 1.06-2.05) were independently associated with higher risk for suicidal ideation, after adjusting for covariates. Impulsivity and anxiety directly increased risk for suicidal ideation regardless of product type used. Hispanic youth had higher risk of suicidal ideation than white youth, while higher levels of SES were protective. CONCLUSION: Cigarette/e-cigarette use, as well as impulsivity and anxiety, directly increase the risk of suicidal ideation. IMPLICATIONS: Clinicians should ask young adults with a history of tobacco use, anxiety or impulsive behavior, about suicidal ideationNicotine prevention and cessation programs might be more effective if they simultaneously target substance use and mental healthCulturally appropriate support is needed for ethnic and racial minority youth and young adults in school, college and at workWhen evaluating and understanding risk, the role of multiple social identities (such as minority status, gender, and SES) is important.

Depressive symptoms predict cannabis vaping initiation among young adults.

BACKGROUND: Young adults in the United States, including college students, have the highest prevalence of cannabis use compared with other age groups. Although cannabis vaping is increasingly prevalent during young adulthood, little is known about factors contributing to the onset of cannabis vaping during this developmental period. METHODS: Participants were 3085 cannabis vaping naïve young adults aged 18-25 years (M = 20.60; SD = 1.80), initially recruited from 24 Texas colleges and participating in a multi-wave, longitudinal study. A survival analysis was conducted to determine if participants reporting elevated depressive symptoms had an increased risk of onset of cannabis vaping over six follow-up waves from fall 2015 to spring 2019 compared to their peers with lower levels of depressive symptoms. Socio-demographic characteristics, time-varying past 30 day substance use, and time-varying peer nicotine vaping were included as covariates in the model. RESULTS: Twenty-five percent of participants initiated cannabis vaping during the four-year study period, with stable initiation rates from 2015 to 2017 but doubling from 2017 to 2019. Analyses, both unadjusted and adjusted for study covariates, indicated that elevated depressive symptoms were significantly associated with an increased risk of cannabis vaping initiation. CONCLUSION: Findings indicate that initiation of cannabis vaping during young adulthood is common, and particularly more likely among those with greater depressive symptoms, thus underscoring the importance of prevention programs that include mental health support services tailored to young adults.

Prevalence and socio-demographic correlates of multi-modal cannabis use among young adults who currently use cannabis.

Cannabis use is common in young adulthood, yet little is known about the prevalence and patterns of multi-modal (i.e., use of more than one mode) cannabis use. Objective: We aimed to (1) determine the past 30-day prevalence of five modes (smoke, vape, edible, dab, other) of cannabis use, (2) describe the prevalence of multi-modal cannabis use (single vs. dual vs. poly-modal), and (3) identify socio-demographic correlates of multi-modal use among young adults. Method: Participants were 764 22-30-year-olds who currently used cannabis from Wave 9 (Spring 2019) of the Marketing and Promotions Across Colleges in Texas Project. Participants were 25.11 years old on average (SD = 1.81), 63.6% female, 38.7% identified as non-Hispanic white, 30.6% as Hispanic/Latino, 13.0% as Asian and 9.4% as Black, and 8.2% identified with two or more races or another race/ethnicity. Bivariate analyses and a multinomial regression were used to examine study questions. Results: Smoking was the most common mode of cannabis use followed by vaping and then edibles. Nearly 43% of participants reported single-modal cannabis use, 33% reported dual-modal use, and 24% reported poly-modal use. Males and those identifying as non-heterosexual were at a greater risk than their counterparts for using multiple modes of cannabis. Participants identifying as Black were at a reduced risk for poly-modal compared to single-modal use. Conclusion: Multi-modal use is common among young adults who currently use cannabis, indicating a need for universal efforts aimed at all young adults. Tailored interventions aimed toward those at elevated risk for multi-modal use also are needed.

Annual hepatitis C testing and positive tests among gay and bisexual men in Australia from 2016 to 2022: a serial cross-sectional analysis of sentinel surveillance data.

OBJECTIVE: Guidelines recommend annual hepatitis C virus (HCV) testing for gay and bisexual men (GBM) with HIV and GBM prescribed HIV pre-exposure prophylaxis (PrEP). However, there is a limited understanding of HCV testing among GBM. We aimed to examine trends in HCV testing and positivity from 2016 to 2022. METHODS: Using sentinel surveillance data, we examined the proportion of GBM with at least one test and the proportion with a positive test in each year for HCV antibody testing among GBM with no previous HCV positive test, HCV RNA testing among GBM with a positive antibody test but no previous positive RNA test (naïve RNA testing), and HCV RNA testing among people who had a previous RNA positive test and a subsequent negative test (RNA follow-up testing). Trends were examined using logistic regression from 2016 to 2019 and 2020 to 2022. RESULTS: Among GBM with HIV, from 2016 to 2019 antibody testing was stable averaging 55% tested annually. Declines were observed for both naïve HCV RNA testing (75.4%-41.4%: p<0.001) and follow-up HCV RNA testing (70.1%-44.5%: p<0.001). Test positivity declined for HCV antibody tests (2.0%-1.3%: p=0.001), HCV RNA naïve tests (75.4%-41.4%: p<0.001) and HCV RNA follow-up tests (11.3%-3.3%: p=0.001). There were minimal or no significant trends from 2020 to 2022.Among GBM prescribed PrEP, antibody testing declined from 2016 to 2019 (79.4%-69.4%: p<0.001) and was stable from 2020 to 2022. Naïve and follow-up HCV RNA testing was stable with an average of 55% and 60% tested each year, respectively. From 2016-2019, the proportion positive from HCV RNA naïve tests declined (44.1%-27.5%: p<0.046) with no significant change thereafter. Positive follow-up HCV RNA tests fluctuated with no or one new positive test among this group in most years. CONCLUSION: The proportion of GBM with positive HCV tests has declined, however a substantial proportion are not tested annually. A renewed focus on HCV testing, and treatment where required, is warranted to achieve HCV elimination among GBM in Australia.

Most commonly used vaping brands by 18-25 year old young adults in Texas-Spring 2023.

PURPOSE: We aimed to determine (1) the most commonly used brands of electronic vaping products (EVPs) by young adults in Texas during Spring 2023, and (2) if brand preferences differ by sociodemographic characteristics, current cigarette smoking, and current cannabis vaping. METHOD: Participants were 2,491 18-25-year-olds (Mean age = 20.6; 62.9% female; 29.7% sexual gender minority; 35.9% non-Hispanic White, 45.0% Hispanic/Latino, 3.5% non-Hispanic Black, 11.6% non-Hispanic Asian, and 4.0% two or more races or another race/ethnicity) enrolled in 21 Texas colleges during February-March 2023 who used EVPs in the past 30-days. RESULTS: Esco Bar was the most popular EVP brand (32.5%), followed by Elf Bar (19%), Vuse (10.1%), and all other brands were used by < 10% of participants. Nearly 20% of participants reported not having a usual brand. Participants who used Esco Bar, Elf Bar, and Puff Bar were younger (i.e., 18-20 years old), female, and Hispanic/Latino. Vuse, JUUL, and Smok were used by participants who were older (i.e., 21-25 years old), male, non-Hispanic white, used EVPs daily, and currently smoked cigarettes. CONCLUSION: The present study extends prior research by providing contemporary data on young adult EVP brand preferences in Texas during Spring 2023. Many of the brands commonly used by young adults (e.g., Esco Bar, Elf Bar) are not currently authorized for marketing or sale by the Food and Drug Administration. Findings underscore a need for additional enforcement efforts that prohibit the distribution and sale of these products to, in turn, prevent EVP use among young adults.

Evaluation of a Project Integrating Financial Incentives into a Hepatitis C Testing and Treatment Model of Care at a Sexual Health Service in Cairns, Australia, 2020-2021.

BACKGROUND: Understanding the effectiveness of novel models of care in community-based settings is critical to achieving hepatitis C elimination. We conducted an evaluation of a hepatitis C model of care with financial incentives that aimed to improve engagement across the hepatitis C cascade of care at a sexual health service in Cairns, Australia. METHODS: Between March 2020 and May 2021, financial incentives were embedded into an established person-centred hepatitis C model of care at Cairns Sexual Health Service. Clients of the Service who self-reported experiences of injecting drugs were offered an AUD 20 cash incentive for hepatitis C testing, treatment initiation, treatment completion, and test for cure. Descriptive statistics were used to describe retention in hepatitis C care in the incentivised model. They were compared to the standard of care offered in the 11 months prior to intervention. RESULTS: A total of 121 clients received financial incentives for hepatitis C testing (antibody or RNA). Twenty-eight clients were hepatitis C RNA positive, of whom 92% (24/28) commenced treatment, 75% (21/28) completed treatment, and 68% (19/28) achieved a sustained virological response (SVR). There were improvements in the proportion of clients diagnosed with hepatitis C who commenced treatment (86% vs. 75%), completed treatment (75% vs. 40%), and achieved SVR (68% vs. 17%) compared to the pre-intervention comparison period. CONCLUSIONS: In this study, financial incentives improved engagement and retention in hepatitis C care for people who inject drugs in a model of care that incorporated a person-centred and flexible approach.

Does the time to nicotine dependence vary by internalizing symptoms for young people who use e-cigarettes? An analysis of the Population Assessment of Tobacco and Health (PATH) study, (Waves 1-5; 2013-2019).

OBJECTIVE: To determine the relationship between past-year internalizing symptoms and the time to first report of signs of nicotine dependence among young people. METHODS: Secondary analysis using data from the Population Assessment of Tobacco and Health (PATH) (Waves 1-5; 2013-2019). The study included 2,102 (N = 5,031,691) young people (age 12-23 years) who reported past-30-day (P30D) e-cigarette use in one or more waves. Kaplan Meier curves, stratified by past year internalizing symptoms were used to estimate the time to the first report of three nicotine dependence symptoms (i.e., use within 30 min of waking, cravings, and really needing to use) following the first P30D e-cigarette use. Cox proportional hazard models were used to estimate crude and adjusted hazard ratios (AHR), comparing any past year internalizing symptoms to no past year internalizing symptoms. RESULTS: We found no significant differences between past year internalizing symptoms and the time to the first report of cravings (AHR = 1.30, 95 % CI = 92-1.85), really needing to use (AHR = 1.31; 95 % CI = 0.92-1.89) and use within 30 min of waking for follow-up times 0-156 weeks (AHR = 0.84; 95 % CI = 0.55-1.30) and > 156 weeks (AHR = 0.41; 95 % CI = 0.04-4.67) respectively. CONCLUSION: Past year internalizing symptoms did not modify the time to the first report of nicotine dependence among youth with P30D e-cigarette use. Further research is needed to understand how changing internalizing symptoms and e-cigarette use frequency influence nicotine dependence over time and, how this relationship impacts cessation behavior.

Risk of Primary Incident Hepatitis C Infection Following Bacterial Sexually Transmissible Infections Among Gay and Bisexual Men in Australia From 2016 to 2020.

Background: In Australia, the incidence of hepatitis C virus (HCV) has declined among gay and bisexual men (GBM) with human immunodeficiency virus (HIV) since 2015 and is low among GBM using HIV preexposure prophylaxis (PrEP). However, ongoing HCV testing and treatment remains necessary to sustain this. To assess the potential utility of sexually transmissible infections (STIs) to inform HCV testing among GBM with HIV and GBM using PrEP, we examined the association between bacterial STI diagnoses and subsequent primary HCV infection. Methods: Data were from a national network of 46 clinics participating in the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance. GBM included had ≥1 HCV antibody negative test result and ≥1 subsequent HCV antibody and/or RNA test. Discrete time survival analysis was used to estimate the association between a positive syphilis, rectal chlamydia, and rectal gonorrhea diagnosis in the previous 2 years and a primary HCV diagnosis, defined as a positive HCV antibody or RNA test result. Results: Among 6529 GBM with HIV, 92 (1.4%) had an incident HCV infection. A prior positive syphilis diagnosis was associated with an incident HCV diagnosis (adjusted hazard ratio, 1.99 [95% confidence interval, 1.11-3.58]). Among 13 061 GBM prescribed PrEP, 48 (0.4%) had an incident HCV diagnosis. Prior rectal chlamydia (adjusted hazard ratio, 2.75 [95% confidence interval, 1.42-5.32]) and rectal gonorrhea (2.54 [1.28-5.05]) diagnoses were associated with incident HCV. Conclusions: Diagnoses of bacterial STIs in the past 2 years was associated with HCV incidence. These findings suggest that STIs might be useful for informing HCV testing decisions and guidelines for GBM with HIV and GBM using PrEP.

Incidence of Breast Cancer in Younger Women: A Canadian Trend Analysis.

Purpose: Breast cancer (BC) incidence is increasing globally. Age-specific BC incidence trend analyses are lacking for women under age 50 in Canada. In this study, we evaluate the incidence trends in breast cancer in women under age 50 in Canada and compare them with corresponding trends among women 50 to 54. Methods: BC case counts were obtained from the National Cancer Incidence Reporting System (1984-1991) and the Canadian Cancer Registry (1992-2019) both housed at Statistics Canada. Population data were also obtained from Statistics Canada. Annual female BC age-specific incidence rates from 1984 to 2019 were derived for the following age groups: 20 to 29, 30 to 39, 40 to 49, 40 to 44, 45 to 49, and 50 to 54. Changes in trends in age-specific BC incidence rates, if any, and annual percent changes (APCs) for each identified trend, were determined using JoinPoint. Results: Statistically significant increasing trends in BC incidence rates were noted for almost all age groups: since 2001 for 20 to 29 (APC = 3.06%, P < .001); since 2009 for 30 to 39 (APC = 1.25%, P = .007); since 1984 for both 40 to 49 (APC = 0.26%, P < .001) and 40 to 44 (APC = 0.19%, P = .011), increased since 2015 for 40 to 49 (APC = 0.77%, P = .047); and since 2005 for 50 to 54 (APC = 0.38%, P = .022). Among women 45 to 49 there was a non-significant increase since 2005 (APC = 0.24, P = .058). Statistically significant average annualized increases in BC incidence rates were observed for each age group studied. Conclusions: Examining age-specific incidence rates formed a more complete picture of BC time trends with significant increasing trends in the incidence of BC among women in their 20s, 30s, 40s, and early 50s. A greater awareness regarding the increasing number of cases of BC in women younger than 50 is critical to allow for earlier diagnosis with its resultant reduced mortality and morbidity.

Time to first report of signs of nicotine dependence among youth who use e-cigarettes and cigarettes in the United States: A nationally representative cohort study, findings from the Population Assessment of Tobacco and Health, 2013-2019.

OBJECTIVE: To determine the time to first report of signs of nicotine dependence among youth exclusive e-cigarette users and compare this time to that for exclusive cigarette users. METHODS: Secondary analysis of data (Waves 1-5; 2013-2019) from the Population Assessment of Tobacco and Health was conducted. Youth never tobacco users in the United States who reported exclusive past-30-day (P30D) e-cigarette or cigarette use (n = 2940, N = 5,391,642) in at least one wave were included in the current analysis. Survival analysis was used to estimate the time to the first report of three nicotine dependence indicators (i.e., "use within 30 minutes of waking"; "cravings" and "really needing to use") following the first report of P30D use. Multivariable Cox proportional hazard models were used to estimate adjusted hazard ratios (aHR). RESULTS: There were no significant differences in the time to first report of "use within 30 minutes of waking" (aHR = 1.1, 95% CI = 0.87-1.40) and "cravings" (aHR = 1.09, 95% CI = 0.81-1.47) between exclusive P30D e-cigarette use and exclusive P30D cigarette use. However, compared to exclusive P30D e-cigarette use, the hazard of first reporting "really needing to use" tobacco was 39% (aHR 1.39; 95% CI: 1.05-1.84) times higher for those who reported exclusive P30D cigarette use after controlling for covariates. CONCLUSION: Compared to exclusive P30D cigarette use, no differences in the time to first report of signs of nicotine dependence ("use within 30 minutes" and "cravings") were observed among exclusive P30D e-cigarette users. Policymakers and regulatory agencies should consider this evidence when assessing the abuse liability of e-cigarette products.

Correlates of suicidal behaviors and genetic risk among United States veterans with schizophrenia or bipolar I disorder.

Persons diagnosed with schizophrenia (SCZ) or bipolar I disorder (BPI) are at high risk for self-injurious behavior, suicidal ideation, and suicidal behaviors (SB). Characterizing associations between diagnosed health problems, prior pharmacological treatments, and polygenic scores (PGS) has potential to inform risk stratification. We examined self-reported SB and ideation using the Columbia Suicide Severity Rating Scale (C-SSRS) among 3,942 SCZ and 5,414 BPI patients receiving care within the Veterans Health Administration (VHA). These cross-sectional data were integrated with electronic health records (EHRs), and compared across lifetime diagnoses, treatment histories, follow-up screenings, and mortality data. PGS were constructed using available genomic data for related traits. Genome-wide association studies were performed to identify and prioritize specific loci. Only 20% of the veterans who reported SB had a corroborating ICD-9/10 EHR code. Among those without prior SB, more than 20% reported new-onset SB at follow-up. SB were associated with a range of additional clinical diagnoses, and with treatment with specific classes of psychotropic medications (e.g., antidepressants, antipsychotics, etc.). PGS for externalizing behaviors, smoking initiation, suicide attempt, and major depressive disorder were associated with SB. The GWAS for SB yielded no significant loci. Among individuals with a diagnosed mental illness, self-reported SB were strongly associated with clinical variables across several EHR domains. Analyses point to sequelae of substance-related and psychiatric comorbidities as strong correlates of prior and subsequent SB. Nonetheless, past SB was frequently not documented in health records, underscoring the value of regular screening with direct, in-person assessments, especially among high-risk individuals.

Chlamydia retesting remains low among young women in Australia: an observational study using sentinel surveillance data, 2018-2022.

BACKGROUND: Chlamydia remains the most notified bacterial sexually transmissible infection in Australia with guidelines recommending testing for re-infection at 3months post treatment. This paper aimed to determine chlamydia retesting and repeat positivity rates within 2-4months among young women in Australia, and to evaluate what factors increase or decrease the likelihood of retesting. METHODS: Chlamydia retesting rates among 16-29-year-old women were analysed from Australian Collaboration for Coordinated Enhanced Sentinel Surveillance of sexually transmissible infection and bloodborne virus (ACCESS) sentinel surveillance data (n =62 sites). Among women with at least one positive test between 1 January 2018 and 31 August 2022, retesting counts and proportions within 2-4months were calculated. Logistic regression was performed to assess factors associated with retesting within 2-4months. RESULTS: Among 8758 women who were positive before 31 August 2022 to allow time for follow up, 1423 (16.2%) were retested within 2-4months, of whom 179 (12.6%) tested positive. The odds of retesting within 2-4months were 25% lower if tested in a coronavirus disease 2019 (COVID-9) pandemic year (2020-2022) (aOR=0.75; 95% CI 0.59-0.95). Among 9140 women with a positive test before 30 November 2022, 397 (4.3%) were retested too early (within 7days to 1month) and 81 (20.4%) of those were positive. CONCLUSIONS: Chlamydia retesting rates remain low with around a sixth of women retested within 2-4months in line with guidelines. Re-infection is common with around one in eight retesting positive. An increase in retesting is required to reduce the risk of reproductive complications and onward transmission.

Working dogs in dynamic on-duty environments: The impact of dark adaptation, strobe lighting and acoustic distraction on task performance.

Sudden changes in sound and light (e.g., sirens and flashing police beacons) are a common component of working dogs' on-duty environment. Yet, how such stimuli impact dogs' ability to perform physical and cognitive tasks has not been explored. To address this shortcoming, we compared the accuracy and time taken for twelve dogs to complete a complex physical and cognitive task, before, during and after exposure to three 'real-world' stimuli: an acoustic distractor (85dB), white strobe lighting (5, 10 & 15 Hz), and exposure to a dazzling white, red, or blue lights. We found that strobe lighting, and to a greater extent, acoustic distraction, significantly reduced dogs' physical performance. Acoustic distraction also tended to impair dogs' cognitive performance. Dazzling lights had no effect on task performance. Most (nine out of twelve) dogs sensitised to the acoustic distraction to the extent of non-participation in the rewarded task. Our results suggest that without effective distractor response training, sudden changes in noise and flickering lights are likely to impede cognitive and physical task performance in working dogs. Repeated uncontrolled exposure may also amplify these effects.

Hepatitis C virus reinfection incidence among gay and bisexual men with HIV in Australia from 2016 to 2020.

BACKGROUND: There is some concern that hepatitis C virus (HCV) reinfection might impact HCV micro-elimination efforts among gay and bisexual men (GBM) with HIV. However, there is a limited understanding of reinfection incidence in the context of unrestricted government-funded HCV treatment. We aimed to estimate HCV reinfection incidence among GBM with HIV in Australia from 2016 to 2020. METHODS: Data were from 39 clinics participating in ACCESS, a sentinel surveillance network for blood borne viruses and sexually transmissible infections across Australia. GBM with HIV who had evidence of treatment or spontaneous clearance with at least one positive HCV RNA test, a subsequent negative HCV RNA test, and at least one additional HCV RNA test between 1st January 2016 and 31st December 2020 were eligible for inclusion. A new HCV RNA positive test and/or detectable viral load was defined as a reinfection. Generalised linear modelling was used to examine trends in reinfection. RESULTS: Among 12 213 GBM with HIV who had at least one HCV test, 540 were included in the reinfection incidence analysis, of whom 38 (7%) had evidence of reinfection during the observation period. Over 1124 person-years of follow-up, the overall rate of reinfection was 3.4/100PY (95% CI 2.5-4.6). HCV reinfection incidence declined on average 30% per calendar year (Incidence Rate Ratio 0.70, 95% CI 0.54-0.91). CONCLUSION: HCV reinfection incidence has declined among GBM with HIV in Australia since government-funded unrestricted DAAs were made available. Ongoing HCV RNA testing following cure and prompt treatment for anyone newly diagnosed is warranted to sustain this.

Priority populations' experiences of isolation, quarantine and distancing for COVID-19: protocol for a longitudinal cohort study (Optimise Study).

INTRODUCTION: Longitudinal studies can provide timely and accurate information to evaluate and inform COVID-19 control and mitigation strategies and future pandemic preparedness. The Optimise Study is a multidisciplinary research platform established in the Australian state of Victoria in September 2020 to collect epidemiological, social, psychological and behavioural data from priority populations. It aims to understand changing public attitudes, behaviours and experiences of COVID-19 and inform epidemic modelling and support responsive government policy. METHODS AND ANALYSIS: This protocol paper describes the data collection procedures for the Optimise Study, an ongoing longitudinal cohort of ~1000 Victorian adults and their social networks. Participants are recruited using snowball sampling with a set of seeds and two waves of snowball recruitment. Seeds are purposively selected from priority groups, including recent COVID-19 cases and close contacts and people at heightened risk of infection and/or adverse outcomes of COVID-19 infection and/or public health measures. Participants complete a schedule of monthly quantitative surveys and daily diaries for up to 24 months, plus additional surveys annually for up to 48 months. Cohort participants are recruited for qualitative interviews at key time points to enable in-depth exploration of people's lived experiences. Separately, community representatives are invited to participate in community engagement groups, which review and interpret research findings to inform policy and practice recommendations. ETHICS AND DISSEMINATION: The Optimise longitudinal cohort and qualitative interviews are approved by the Alfred Hospital Human Research Ethics Committee (# 333/20). The Optimise Study CEG is approved by the La Trobe University Human Ethics Committee (# HEC20532). All participants provide informed verbal consent to enter the cohort, with additional consent provided prior to any of the sub studies. Study findings will be disseminated through public website (https://optimisecovid.com.au/study-findings/) and through peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT05323799.