This is a four-year University of Bristol Scholarship to conduct research "Estimating trends in the initiation of injecting drug use and implications for global elimination of HIV and hepatitis C virus". The student will be supervised by Associate Professor Jack Stone, Dr Kennedy Kipkoech and Professor Peter Vickerman.

Background of the project:
People who inject drugs (PWID) have one of the highest risks of HIV and hepatitis C virus (HCV) infection, and are one of the most vulnerable populations in our society[1-2]. This high-risk group represents a key target group in the global agenda to eliminate HIV/AIDS and HCV by 2030, led by the World Health Organisation. Patterns of injecting drug use initiation are thought to vary globally and be influenced by ‘big events’ such as conflict, economic crises and changes in drug supply. However, trends in the initiation of injecting drug use are understudied but could have important implications for disease transmission and intervention programming towards achieving elimination targets. Previous analyses have used repeat cross-sectional surveys among PWID to estimate how the number of people who start injecting each year in England and Scotland have changed over time [3]. However, these methods have not been applied in other settings, especially in lower and middle income countries, and do not account for potential changes in mortality over time.

Aims and Objectives:
Use data from repeated cross-sectional surveys (e.g. in Georgia, Ukraine, Pakistan, Kenya, US and India) to estimate trends in the initiation of injecting drug use and so the population size of people who inject drugs across a range of different settings.
Use epidemic modelling to assess how dynamic changes in the population of people who inject drugs over time affect HIV and/or HCV transmission patterns over time and the implications for intervention programming and disease elimination.

Methodology:
Although the student will be encouraged to learn several methodological skills, training will focus on specific methodologies associated with each of the aims: statistical analyses and bayesian inference (SA1) and epidemic modelling (SA2). SA1 involves using Bayesian methods to infer changes in the number of people who start injecting over time and so the population size of PWID. SA1 will extend previous methods applied for the UK [3] to account for changes in mortality over time e.g. due to changes in HIV prevalence and HIV treatment scale-up. SA2 involves developing a dynamic mathematical model examining the implications of trends in injecting initiation on disease transmission and resources needed for disease elimination. To support data access and analysis, there are opportunities for international travel. There are also opportunities to contribute to other projects led by other team members including ongoing systematic reviews. Overall, the project and learning environment will support the student in developing a well-rounded skillset in epidemiology and epidemic modelling applicable to the study of other infectious diseases and research sectors.

[1] Artenie, Stone,…Vickerman. Lancet Gastrol Hepatol 2023. DOI: 10.1016/S2468-1253(23)00018-3
[2] Degenhardt et al. Lancet Glob Health 2023. DOI: 10.1016/S2214-109X(23)00057-8
[3] Lewer et al. Addiction 2022 DOI: 10.1111/add.15911

University of Bristol Scholarship - How to apply
You can submit an application via the University of Bristol application portal: Start your application | Study at Bristol | University of Bristol selecting the relevant 4-year PhD programme, e.g. “Population Health Sciences (PhD)”.

Search for your programme and select ‘apply’. Please choose the September 2025 start date.

Link to prospectus pages for Population Health Sciences giving entry requirements and admissions statement: Study at Bristol | Population Health Sciences.

In the funding section of the application form, please indicate “University of Bristol Scholarship”.

In the research section please enter the project title of the scholarship you are applying for along with the supervisor's name. You can upload a blank document instead of the research statement, which is not needed.

We are keen to support applicants from minority and under-represented backgrounds (based on protected characteristics) and those who have experienced other challenges or disadvantages. We encourage you to use your personal statement to ensure we can take these factors into account.

We will also be running a pre-application online workshop and Q&A session on how to prepare a PhD application on 5th December 2024 04:00 PM GMT; if you would like to register for this workshop then please sign up here.

The application deadline is 4pm GMT on Monday 6th January 2025. The anticipated start date for this project is September 2025.

Funding Notes:
This project is available for both home and international students. The University of Bristol Scholarship is for four years, and it includes an annual stipend set at the current UKRI recommendation of £19,237. Tuition fees and research costs are fully supported by the studentship, as well as an allowance for paid sick leave and parental leave, in addition to 5 weeks of paid leave each year.