About the project
We are seeking a talented graduate in a relevant numerical discipline (Mathematics, physics, engineering etc..) wishing to develop strong interdisciplinary skills at the interface of public health, epidemiology, and infectious disease modelling. The PhD studentship would start in October 2021, being based in Bristol but jointly supervised by infectious disease modellers in Bristol and HIV treatment and prevention researchers in Cardiff. The expanding Bristol modelling group (led by Peter Vickerman) consists of over 20 infectious disease modellers based in Population Health Sciences (Bristol Medical School, University of Bristol), through which a wide range of collaborative, multi-disciplinary research takes place involving clinicians, epidemiologists, health economists, public health physicians and statisticians. It is an internationally-leading institution in population health research. The student will also become an active member of Cardiff’s Centre for Trials Research (120 members) led by Karenza Hood, which has several ongoing studies in the area of HIV treatment and prevention. Both teams have thriving and expanding groups of PhD students working on population health policy relevant areas.

Project overview
Men who have sex with men (MSM) are at high risk of HIV infection. Behavioural, legal and social factors all contribute to this heightened risk. Epidemiological analysis and modelling will be used to explore the role of context-specific factors (e.g. chemsex in UK, stigma and criminalisation in Africa) in elevating HIV transmission among MSM.

Project description
Globally, men who have sex with men (MSM) are 28 times more likely to acquire HIV than other men. Biological, behavioural, legal and social factors all contribute to increasing the risk of HIV transmission among MSM.
Stigma and discrimination towards MSM persists, with same-sex sexual activity criminalised in 72 countries (mostly Africa), limiting access to HIV prevention and care services. In Sub-Saharan Africa (SSA), where HIV prevalence amongst MSM is greatest (~18%), HIV testing and status awareness are associated negatively with severity of anti-LGBT legislation. Twenty-four percent of MSM in SSA and 18% in Eastern Europe/Central Asia (EECA) report having been arrested or convicted for being MSM, which is associated with poorer access to HIV prevention and care, including being half as likely to access condoms in SSA.
In high-income countries, chemsex, the use of psychoactive and performance-enhancing drugs before/during planned sexual events, has emerged as a key risk behaviour among MSM. In London, MSM engaging in chemsex are 5 times more likely to be diagnosed with HIV than other MSM, with similar increases in risk for other sexually transmitted infections.
The World Health Organisation and the Joint United Nations Programme on HIV/AIDS (UNAIDS) have set targets for eliminating HIV. To meet these targets among MSM, it is important to understand how specific factors increase the risk of HIV transmission and so aid the development of interventions to reduce these risks. In light of this, we propose to:

1. Utilise data from systematic reviews of how chemsex is associated with HIV transmission and related risk behaviours, to undertake modelling of the potential contribution of chemsex to HIV transmission in a range of HIV epidemics.
2. For contrasting global settings, utilise available epidemiological data to develop and parameterise HIV transmission models to investigate the role of context-specific factors (including chemsex, stigma, history of arrest) in driving HIV transmission among MSM, incorporating their effects on risk behaviours and uptake of prevention and treatment services.
3. Through modelling, assess the impact of different HIV prevention and treatment interventions or structural interventions that may reduce the harms modelled in 2.

Through existing collaborations, we will model settings in UK (likely Wales), EECA (likely Ukraine or Georgia) and SSA (likely Senegal or Zambia), with travel occurring to these sites. Collaborators with expertise in MSM and sexual health research will guide the modelling and interventions considered. The project including training in infectious disease modelling and other epidemiological methods. The PhD student will be encouraged to publish their work, which will influence policy through presenting at international conferences and by working collaboratively with key stakeholders and MSM in each setting and through liaising with UNAIDS.
Candidate requirements: Applications are welcome from highly numerate individuals across a wide range of disciplines who have, or are expected to achieve, at least a 2:1 or higher degree (or equivalent) and/or with a research Masters degree in a relevant discipline
How to apply: Student applications can be made via the GW4 BioMed website: https://www.gw4biomed.ac.uk. The closing date for applications is 5pm on Monday, 23rd November 2020. Shortlisted applicants will be invited for an informal interview (over the phone, on Skype or Zoom) with the lead supervisors (Prof Peter Vickerman and Dr Jack Stone) between Monday 4th and Friday 15th January 2021. The formal interview will be held virtually on 20-21 January 2021.
A GW4 BioMed MRC DTP studentship includes full tuition fees at the UK/Home rate, a stipend at the minimum UKRI rate (£15,285 for 20/21), a Research & Training Support Grant (RTSG) valued between £2,000-£5,000 per year and £300 annual travel and conference grant based on a 3.5-year full-time studentship. These funding arrangements will be adjusted pro-rata for part-time studentships.
The GW4 BioMed MRC DTP studentships are available to UK, EU and International applicants. International students (including EU applicants) are now eligible to apply for these studentships but should note that they may have to pay the difference between the home UKRI fee and the International student fee.
For any informal queries about the studentship, please contact Peter Vickerman and Jack Stone (peter.vickerman@bristol.ac.uk and jack.stone@bristol.ac.uk)