Serosurvey for Japanese encephalitis virus antibodies following an outbreak in an immunologically naïve population, Victoria, 2022: a cross-sectional study.

OBJECTIVES: To 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 DESIGN: Cross-sectional serosurvey (part of a national JEV serosurveillance program). SETTING: Three northern Victorian local public health units (Ovens Murray, Goulburn Valley, Loddon Mallee), 8 August - 1 December 2022. PARTICIPANTS: People 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 MEASURES: Seroprevalence of JEV IgG antibody, overall and by selected factors of interest (occupations, water body exposure, recreational activities and locations, exposure to animals, protective measures). RESULTS: 813 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). CONCLUSIONS: People 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.

Emergency health service contact and reincarceration after release from prison: A prospective cohort study.

BACKGROUND: Adults released from prison often have complex health needs. They are at high risk of poor health outcomes and reincarceration, with health service use unlikely to be planned. AIMS/HYPOTHESES: To determine the incidence of emergency health service (EHS) use, ambulance attendance and/or emergency department presentation, among 1,181 adults released from Australian prisons. We hypothesised that EHS contact would be associated with increased reincarceration risk. METHODS: Baseline surveys were conducted within 6 weeks before release. Postrelease EHS contacts and reincarceration were identified through prospective data linkage. For each participant, EHS contacts within a 24-hour period were combined to make an episode. We used Cox proportional hazards regression to examine the relationship between EHS episodes and reincarceration, controlling for covariates. RESULTS: More than half (53.3%) of participants had at least one EHS contact over a median of 25.6-month follow-up. In adjusted analyses, compared to those with no EHS contacts, the hazard of reincarceration was greater for participants who had one to three EHS episodes (hazard ratio [HR] = 1.84; 95% confidence interval [CI] [1.48, 2.29]) or four or more (HR = 2.35; 95% CI [1.67, 3.29]). CONCLUSIONS/IMPLICATIONS FOR PRACTICE: Emergency department attendance by people with a history of imprisonment may be indicative of wider decompensation. Improved management of such patients may improve health outcomes and have collateral benefits for reducing reincarceration.

The incidence of tuberculosis among adolescents and young adults: a global estimate.

Historical data show that the risk of tuberculosis increases dramatically during adolescence, and young people face unique challenges in terms of case detection and effective treatment. However, little is known about the burden of tuberculosis among young people in the modern era. This study aimed to provide the first estimates of the global and regional incidence of tuberculosis among young people aged 10-24 years.Using the World Health Organization (WHO) database of tuberculosis notifications for 2012, we estimated the burden of tuberculosis among young people by WHO region. Adjustments were made for incomplete age disaggregation and underreporting, using supplementary data from several countries representing diverse tuberculosis epidemics.We estimate that 1.78 million (uncertainty interval (UI) 1.23-3.00 million) young people developed tuberculosis in 2012, accounting for 17% of all new tuberculosis cases globally. Young people in the WHO South East Asian Region (721 000, UI 473 000-1.35 million) and the WHO African Region (534 000, UI 359 000-912 000) experienced the greatest number of tuberculosis episodes.Young people suffer a considerable burden of tuberculosis. Age-specific burden of disease estimation for this age group is complicated by incomplete age disaggregation of tuberculosis data, highlighting the importance of continued surveillance system strengthening.

Incidence and prevalence of bacteriologically confirmed pulmonary tuberculosis among adolescents and young adults: a systematic review.

The burden of tuberculosis (TB) among adolescents and young adults in endemic settings is poorly characterised. This study aimed to review published and unpublished estimates of the incidence and prevalence of bacteriologically confirmed TB among young people aged 10-24 years. We searched PubMed and World Health Organization archives for publications and unpublished data from population-based epidemiologic studies reporting confirmed pulmonary TB among young people, conducted from January 2000 onwards. We identified 27 publications and unpublished data from two national surveys, representing a total of 26 studies in 19 countries. The prevalence of bacteriologically confirmed TB ranged from 45 to 799 per 100 000 in the Asia-Pacific region and from 160 to 462 per 100 000 in African settings. We did not identify any epidemiologic studies of confirmed TB among adolescents living with human immunodeficiency virus (HIV). Many studies were excluded due to absent or inadequately reported age-specific data. Adolescents and young adults living in many endemic settings appear to be at substantial risk of developing active TB. There is a pressing need to improve the routine reporting of age in epidemiologic studies of TB, and to generate high-quality epidemiologic data regarding TB among adolescents living with HIV.

Incidence and correlates of hepatitis C virus infection in a large cohort of prisoners who have injected drugs.

BACKGROUND: Hepatitis C virus (HCV) infection is common among prisoners, particularly those with a history of injecting drug use (IDU). Incarcerated people who inject drugs frequently report high-risk injecting practices both in prison and in the community. In spite of rising morbidity and mortality, utilisation of HCV-related services in Australia has been persistently low. This study aimed to describe the incidence, prevalence and correlates of HCV seropositivity in a large cohort of prisoners who have injected drugs, and to identify correlates of receiving confirmation of active infection. METHODS: Data-linkage to a State-wide statutory notifiable diseases surveillance system was used to investigate the incidence of notified HCV seropositivity, seroconversion and confirmed HCV infection in a cohort of 735 prisoners with a history of IDU, over 14 years of follow up. Hepatitis C test results from prison medical records were used to identify correlates of testing positive in prison. RESULTS: The crude incidence of HCV notification was 5.1 cases per 100 person-years. By the end of follow up, 55.1% of the cohort had been the subject of a HCV-related notification, and 47.4% of those tested in prison were HCV seropositive. In multivariable analyses, injecting in prison was strongly associated with HCV seropositivity, as was opioid use compared to injection of other drugs. The rate of reported diagnostic confirmation among those with notified infections was very low, at 6.6 confirmations per 100 seropositive participants per year. CONCLUSIONS: Injecting drugs in prison was strongly associated with HCV seropositivity, highlighting the need for increased provision of services to mitigate the risk of transmission within prisons. Once identified as seropositive through screening, people with a history of IDU and incarceration may not be promptly receiving diagnostic services, which are necessary if they are to access treatment. Improving access to HCV-related services will be of particular importance in the coming years, as HCV-related morbidity and mortality is increasing, and next generation therapies are becoming more widely available.

Quantifying the rates of late reactivation tuberculosis: a systematic review.

The risk of tuberculosis is greatest soon after infection, but Mycobacterium tuberculosis can remain in the body latently, and individuals can develop disease in the future, sometimes years later. However, there is uncertainty about how often reactivation of latent tuberculosis infection (LTBI) occurs. We searched eight databases (inception to June 25, 2019) to identify studies that quantified tuberculosis reactivation rates occurring more than 2 years after infection (late reactivation), with a focus on identifying untreated study cohorts with defined timing of LTBI acquisition (PROSPERO registered: CRD42017070594). We included 110 studies, divided into four methodological groups. Group 1 included studies that documented late reactivation rates from conversion (n=14) and group 2 documented late reactivation rates in LTBI cohorts from exposure (n=11). Group 3 included 86 studies in LTBI cohorts with an unknown exposure history, and group 4 included seven ecological studies. Since antibiotics have been used to treat tuberculosis, only 11 studies have documented late reactivation rates in infected, untreated cohorts from either conversion (group 1) or exposure (group 2); six of these studies lasted at least 4 years and none lasted longer than 10 years. These studies found that tuberculosis rates declined over time, reaching approximately 200 cases per 100 000 person-years or less by the fifth year, and possibly declining further after 5 years but interpretation was limited by decreasing or unspecified cohort sizes. In cohorts with latent tuberculosis and an unknown exposure history (group 3), tuberculosis rates were generally lower than those seen in groups 1 and 2, and beyond 10 years after screening, rates had declined to less than 100 per 100 000 person-years. Reinfection risks limit interpretation in all studies and the effect of age is unclear. Late reactivation rates are commonly estimated or modelled to prioritise tuberculosis control strategies towards tubuculosis elimination, but significant gaps remain in our understanding that must be acknowledged; the relative importance of late reactivation versus early progression to the global burden of tuberculosis remains unknown.

Adolescent tuberculosis.

Adolescence is characterised by a substantial increase in the incidence of tuberculosis, a known fact since the early 20th century. Most of the world's adolescents live in low-income and middle-income countries where tuberculosis remains common, and where they comprise a quarter of the population. Despite this, adolescents have not yet been addressed as a distinct population in tuberculosis policy or within tuberculosis treatment services, and emerging evidence suggests that current models of care do not meet their needs. This Review discusses up-to-date information about tuberculosis in adolescence, with a focus on the management of infection and disease, including HIV co-infection and rifampicin-resistant tuberculosis. We outline the progress in vaccine development and highlight important directions for future research.

Cost-utility analysis of low-intensity case management to increase contact with health services among ex-prisoners in Australia.

OBJECTIVES: The economic burden of incarceration is substantial in Australia. People released from prison are at high risk of poor health and this is an important predictor of recidivism. The 'Passports Study' was a randomised controlled trial of an intervention designed to increase health service utilisation after release from prison. The aim of this study is to conduct a cost-utility analysis of this transitional programme. SETTING: Australia DESIGN: A hybrid simulation model was developed to estimate the changes to total economic costs and effectiveness expressed as quality-adjusted life-years (QALYs) from the adoption of the 'Passports' intervention compared with the control group. Model parameters were informed by linked data from Queensland Corrective Services, Medicare, Pharmaceutical Benefits Scheme, Queensland Hospital Admission Patient Data Collection, Emergency Department Information System and National Death Index. Health-related quality of life was measured using the Short-Form 8 Health Survey (SF-8). The primary outcomes were the costs and estimated QALYs associated with the intervention group and the control group. Probabilistic sensitivity analysis was conducted to test parameter uncertainties. RESULTS: Compared with the control group where no attempt was made to encourage health service utilisation, an average participant in the intervention group incurred an extra cost of AUD 1790 and experienced slightly reduced QALYs, which indicated that the intervention was dominated in the baseline analysis. Probabilistic sensitivity analysis revealed that the transitional programme had a low probability of being cost-effective with the outcome measures selected. CONCLUSION: The findings of this study do not provide economic evidence to support the widespread adoption of the Passports intervention. Due to the reductionist nature of the cost-utility approach, it may be that important health-related benefits have been omitted. Another research approach using a wider range of health-related measures might generate different conclusions.

Use of multiple data sources to estimate hepatitis C seroprevalence among prisoners: A retrospective cohort study.

Hepatitis C is a major cause of preventable morbidity and mortality. Prisoners are a key population for hepatitis C control programs, and with the advent of highly effective therapies, prisons are increasingly important sites for hepatitis C diagnosis and treatment. Accurate estimates of hepatitis C prevalence among prisoners are needed in order to plan and resource service provision, however many prevalence estimates are based on surveys compromised by limited and potentially biased participation. We aimed to compare estimates derived from three different data sources, and to assess whether the use of self-report as a supplementary data source may help researchers assess the risk of selection bias. We used three data sources to estimate the prevalence of hepatitis C antibodies in a large cohort of Australian prisoners-prison medical records, self-reported status during a face-to-face interview prior to release from prison, and data from a statewide notifiable conditions surveillance system. Of 1,315 participants, 33.8% had at least one indicator of hepatitis C seropositivity, however less than one third of these (9.5% of the entire cohort) were identified by all three data sources. Among participants of known status, self-report had a sensitivity of 80.1% and a positive predictive value of 97.8%. Any one data source used in isolation would have under-estimated the prevalence of hepatitis C in this cohort. Using multiple data sources in studies of hepatitis C seroprevalence among prisoners may improve case detection and help researchers assess the risk of selection bias due to non-participation in serological testing.