Sex, drugs and intersecting risks : HIV among people who belong to more than one key population in the United States

Background The HIV epidemic in the United States (US) is mainly concentrated in so-called ‘key populations’ including men who have sex with men (MSM) and people who inject drugs (PWID). In addition, other groups such as people of low socioeconomic status and people belonging to some ethnic minorities have a higher prevalence of HIV. Globally, people who exchange sex for money or drugs are recognised as another key population with high HIV prevalence, but there is limited recent data from rigorous studies in the United States on HIV prevalence among people who exchange sex. High prevalence among certain groups may be a combination of individual risk behaviours such as condomless sex, drug use and unsafe injection practices, and structural factors such as poverty, violence and residential segregation that can impact HIV risk indirectly. This thesis examines whether, among populations known to be at high risk for HIV, prevalence is higher among those who belong to more than one key population or vulnerable group and for whom several risk factors intersect. Furthermore, it examines sociodemographic factors and sexual and drug-use risk behaviours in these populations and how they may be relevant to HIV acquisition and transmission. Methods Data: I worked with the US National HIV Behavioral Surveillance System (NHBS), which is a surveillance system that collects data from three populations at high risk for HIV in annual rotating cycles: men who have sex with men (MSM), people who inject drugs and heterosexuals at increased risk of HIV (referred to as ‘IDU’ and ‘HET’, respectively). We recruited participants for all three cycles in around 20 large US cities on an annual rotating schedule. For the IDU and HET cycles, we use respondent-driven sampling (RDS), which is a sampling method specifically designed to reach hidden populations and approximate a random sample and where participants recruit each other using coupons. In 2016 I led a pilot data collection focused specifically on women in five cities who exchange sex, also using RDS. During the MSM cycle we recruited participants through venue-based sampling which allows random sampling of venues in a city, time-slots within venues and individual men attending the venue. In all cycles participants take an interviewer-administered survey asking about demographic characteristics, sexual and drug-use risk behaviours and access to services such as frequency of HIV testing and use of health care and preventive services. Participants are also offered a rapid HIV test and receive an incentive for taking the survey and the HIV test. Analysis: For Papers 1 and 2, I looked at women who inject drugs and MSM to examine whether people who exchange sex are more likely to be HIV-infected, including being HIV-positive but unaware of one’s positive status (HIV-positive–unaware), compared with those who do not exchange sex belonging to the same populations. Paper 3 estimates the HIV prevalence among women who exchange sex and compares it with the prevalence among women of low socioeconomic status who do not exchange sex from the same cities three years earlier. In these papers, exchange sex is defined as having had oral, vaginal or anal sex with a male partner in the past 12 months. In Paper 4 I used a subset of the IDU survey data to examine whether MSM who inject drugs (MSM–IDU) are more likely to be HIV infected if they report methamphetamine as their primary drug compared with other drugs. For bivariable and multivariable analyses in Papers 1, 2 and 4 I used generalised estimating equations (GEE), in PROC GENMOD in SAS v. 9.2 or 9.3. The GEE method enables analyses of clustered data where observations in a cluster are thought to be more similar to each other than to other observations. For Paper 3 we used RDSAT to estimate the prevalence of HIV and risk behaviours among women who exchange sex. Results In Paper 1, 10% of women who injected drugs and exchange sex were HIV infected. There was no statistically significant difference in HIV prevalence between those who exchanged sex and those who did not (10.0% vs 7.4%, P = 0.33). However, those who exchanged sex were more likely to be HIV-positive but unaware of their positive status (HIV-positive–unaware) compared with those who did not exchange sex: 5.0% vs 2.6% (P = 0.01). This difference remained significant in multivariable analysis with an adjusted prevalence ratio (aPR) of 1.97 (95% CI 1.31–2.97). In Paper 2, HIV prevalence among MSM who exchanged sex was higher than among MSM who did not (29.1% vs 17.7%, P < 0.001). However, this difference became non-significant in multivariable analysis. MSM who exchanged sex were also more likely to be HIV-positive–unaware than those who did not exchange sex (13.2% vs 5.6%, P ≤ 0.001) and this difference remained in multivariable analysis (aPR 1.34, 95% CI 1.05–1.69). In Paper 3, the prevalence of HIV among women who exchanged sex was 4.9%, approximately three times as high as the prevalence of HIV among women of low socioeconomic status who did not exchange sex (1.6%), and almost nine times as high compared to women in the general population (0.55%). In Paper 4, MSM who primarily injected methamphetamine were significantly more likely to be HIV-positive (29.3%) than MSM who primarily injected other drugs (15.5%, aPR 1.48, 95% CI 1.08–2.03). This association was mediated by sexual risk behaviours, but not drug-use risk behaviours. Among people who exchange sex, and among MSM who inject methamphetamine, sexual and drug-use risk behaviours were common, putting people at risk for HIV acquisition as well as onward transmission. Exchange sex was furthermore common among people living in poverty, homelessness or with other markers of low socioeconomic status. Conclusions The populations studied in this thesis are already known to be at high risk for HIV. This thesis demonstrates that HIV prevalence – in particular the prevalence of being HIV positive but unaware of one’s status – is high among people who belong to more than one key population or vulnerable group. Sexual and drug-use risk behaviours are common. To address the risk for HIV acquisition and onward transmission it is essential to consider a variety of services around prevention, including harm reduction, and testing and linkage to care and treatment. However, narrowly targeted services focusing on a single key population such as people who inject drugs or MSM may not adequately address the needs of those who belong to more than one key population. Additionally, the higher-order structural factors that put individuals and communities at risk for HIV must be addressed

A pilot sentinel surveillance system to monitor treatment and treatment outcomes of chronic hepatitis B and C infections in clinical centres in three European countries, 2019

Hepatitis B; Hepatitis C; SurveillanceHepatitis B; Hepatitis C; VigilanciaHepatitis B; Hepatitis C; VigilànciaBackgroundThe World Health Organization European Action Plan 2020 targets for the elimination of viral hepatitis are that > 75% of eligible individuals with chronic hepatitis B (HBV) or hepatitis C (HCV) are treated, of whom > 90% achieve viral suppression.AimTo report the results from a pilot sentinel surveillance to monitor chronic HBV and HCV treatment uptake and outcomes in 2019.MethodsWe undertook retrospective enhanced data collection on patients with a confirmed chronic HBV or HCV infection presenting at one of seven clinics in three countries (Croatia, Romania and Spain) for the first time between 1 January 2019 and 30 June 2019. Clinical records were reviewed from date of first attendance to 31 December 2019 and data on sociodemographics, clinical history, laboratory results, treatment and treatment outcomes were collected. Treatment eligibility, uptake and case outcome were assessed.ResultsOf 229 individuals with chronic HBV infection, treatment status was reported for 203 (89%). Of the 80 individuals reported as eligible for treatment, 51% (41/80) were treated of whom 89% (33/37) had achieved viral suppression. Of 240 individuals with chronic HCV infection, treatment status was reported for 231 (96%). Of 231 eligible individuals, 77% (179/231) were treated, the majority of whom had received direct acting antivirals (99%, 174/176) and had achieved sustained virological response (98%, 165/169).ConclusionTreatment targets for global elimination were missed for HBV but not for HCV. A wider European implementation of sentinel surveillance with a representative sample of sites could help monitor progress towards achieving hepatitis control targets.The study was supported by the European Centre for Disease Prevention and Control (ECDC) as part of the contract “Sentinel surveillance of hepatitis B and C in the EU/EEA – feasibility, assessment, protocol development and pilot (NP/2019/OCS/10528)”

Traumatic Pulmonary Pneumatoceles (Pseudocyst)

Introduction: Traumatic pulmonary parenchymal cavitary lesions (TPPCs) are pulmonary pseudocysts raiding secondary to lung contusion. Method: To provide an overview of the etiology, presentation, diagnosis and treatment of TPPCs, and to discuss this in the context of a cohort of 12 retrospectively reviewed patients with TPPCs presenting to Sahlgrenska University Hospital, Gothenburg, Sweden, from January 2014 to December 2016. Between January 2014 and December 2016, a total of twelve trauma patients presented to Sahlgrenska University Hospital with TPPC following blunt trauma. Results: TPPCs are of limited clinical consequence. Inexperienced clinicians may treat these inappropriately. A Computed Tomography (CT) scan is the investigation of choice. Treatment is symptomatic. Intervention is indicated only in case of complications

Health Impacts of Catastrophic Climate Change: Expert Workshop. Avoid Dangerous Climate Change (AVOID)

Climate change is likely to have serious and significant impacts on human population health. The mechanisms by which climate change may affect health are becoming better understood. Current quantitative methods of estimating future health impacts rely on disease-specific models that primarily describe relationships between mean values of weather variables and health outcomes and do not address the impacts of extreme events or weather disasters. Extreme events have the potential to disrupt community function, which is of concern for decision-makers. Estimating the magnitude and extent of impacts from low probability high impact events is challenging because there is often no analogue that can provide relevant evidence and that take into account the complexity of factors determining future vulnerability and health impacts (the social determinants of health)

Power Increase Limits to Prevent Pellet-Cladding Interaction : Calculation of Strain- and Fission Gas Release Margins

With a growing share of intermittent electrical energy sources in the national grid of Sweden, areview of the safety of using nuclear power for flexible operation is necessary. Today nuclearpower is used as base load power and when examining challenges of flexible power operation,the risk for Pellet-Cladding Interaction (PCI), stands out. Vattenfall Nuclear Fuel lack a methodof calculating the PCI risk which this study will develop. It does this by mapping the risk for PCIthrough calculating power increase margins, in terms of ΔLHGR for full and flexible poweroperation. The results show that cladding strain for all simulated power levels is the limitingfactor. The time at which fuel remain at reduced power also has a large impact and the speed atwhich the PCI margin deteriorates has been calculated. Data from Westinghouse show that theresults compare relatively well for similar experimental set ups with some systemicconservatism. The automated library of code can be easily used to calculate the PCI risk for fuelin the future. The risk for PCI when returning to fuel power, per a Westinghouse conferencepaper, significantly reduces and should be investigated with the use of provided code. Possiblelimits with this study, however unquantified, are the use of 100 W/cm transient speed and theuse of full power axial profiles for reduced power operation in simulations

Temporal Convolutional Networks in Lieu of Fuel Performance Codes : Conceptual Study Using a Cladding Oxidation Model

Fuel performance codes are used to demonstrate with confidencethat nuclear fuel rods will sustain normal operation and transientevents without being damaged. However, the execution time of a typ-ical fuel rod simulation ranges from tens of seconds to minutes which can be impractical in certain applications. In the scope of this work,at least two such applications are identified; code-calibration and fuelcore evaluations. In both of these cases, possible improvements can be obtainedby creating neural network surrogate models. For code calibration,a Deep Neural Network is enough since calibration is performed onmodel constants. But for full-core evaluations, a surrogate model mustbe able to predict a time-dependent target as a function of a time-dependent input. In this work, Temporal Convolutional Networks are investigated for the second application. In both applications, targetdata are generated with a Cladding Oxidation Model. The result of the study shows that both models succeeded in their respective tasks with good performance metrics. However, furtherwork is needed to increase the number of input and target variablesthat the Deep Neural Network can handle, verify the flexibility ofinput data files for the TCN, try out the TCN on a real code, and combine the two models and achieve a broader set of use-cases.Kursnamn: Fördjupande projektarbete i energisystemKurskod: 1FA394</p

Power Increase Limits to Prevent Pellet-Cladding Interaction : Calculation of Strain- and Fission Gas Release Margins

With a growing share of intermittent electrical energy sources in the national grid of Sweden, areview of the safety of using nuclear power for flexible operation is necessary. Today nuclearpower is used as base load power and when examining challenges of flexible power operation,the risk for Pellet-Cladding Interaction (PCI), stands out. Vattenfall Nuclear Fuel lack a methodof calculating the PCI risk which this study will develop. It does this by mapping the risk for PCIthrough calculating power increase margins, in terms of ΔLHGR for full and flexible poweroperation. The results show that cladding strain for all simulated power levels is the limitingfactor. The time at which fuel remain at reduced power also has a large impact and the speed atwhich the PCI margin deteriorates has been calculated. Data from Westinghouse show that theresults compare relatively well for similar experimental set ups with some systemicconservatism. The automated library of code can be easily used to calculate the PCI risk for fuelin the future. The risk for PCI when returning to fuel power, per a Westinghouse conferencepaper, significantly reduces and should be investigated with the use of provided code. Possiblelimits with this study, however unquantified, are the use of 100 W/cm transient speed and theuse of full power axial profiles for reduced power operation in simulations

Temporal Convolutional Networks in Lieu of Fuel Performance Codes : Conceptual Study Using a Cladding Oxidation Model

Fuel performance codes are used to demonstrate with confidencethat nuclear fuel rods will sustain normal operation and transientevents without being damaged. However, the execution time of a typ-ical fuel rod simulation ranges from tens of seconds to minutes which can be impractical in certain applications. In the scope of this work,at least two such applications are identified; code-calibration and fuelcore evaluations. In both of these cases, possible improvements can be obtainedby creating neural network surrogate models. For code calibration,a Deep Neural Network is enough since calibration is performed onmodel constants. But for full-core evaluations, a surrogate model mustbe able to predict a time-dependent target as a function of a time-dependent input. In this work, Temporal Convolutional Networks are investigated for the second application. In both applications, targetdata are generated with a Cladding Oxidation Model. The result of the study shows that both models succeeded in their respective tasks with good performance metrics. However, furtherwork is needed to increase the number of input and target variablesthat the Deep Neural Network can handle, verify the flexibility ofinput data files for the TCN, try out the TCN on a real code, and combine the two models and achieve a broader set of use-cases.Kursnamn: Fördjupande projektarbete i energisystemKurskod: 1FA394</p