Imperial College London


Faculty of MedicineSchool of Public Health

Honorary Research Fellow



r.baggaley Website




Praed StreetSt Mary's Campus





I am a Sir Henry Wellcome Postdoctoral Research Fellow in infectious disease epidemiology. My research involves using mathematical modelling to investigate the effects of various interventions on HIV transmission, such as antiretroviral therapy (ART), treatment of herpes simplex virus and microbicides. I am also researching the effects that coinfections such as malaria, tuberculosis, helminths and sexually transmitted infections may have on HIV transmission by enhancing HIV set-point viral load during the long asymptomatic period of infection. Related to my work on the role of ART in HIV control, I am interested in the emergence and spread of antiretroviral drug resistance through populations, particularly sub-Saharan Africa, as antiretroviral therapy coverage is scaled-up in this region.


Through my experience of mathematical modelling I have appreciated the importance of appropriate and accurate estimation of model parameters and as a result have become heavily involved in the systematic review (and meta-analysis, where appropriate) of key model parameters: HIV infectiousness and sexual behaviour.  I have been working on estimating HIV transmission risk for various modes of transmission including: HIV risk per act and HIV transmission rate among discordant couples for heterosexual sex, and risks through anal sex, oral sex, blood transfusion and needlestick injury. Most recently I have compared HIV transmission risks reported from prospective discordant couple studies (couples with one infected and one uninfected partner, followed through time to measure rate of transmission to the initially uninfected partner) for couples where the infected partner was receiving ART to those with no ART use (results in press).


Regarding behaviour, I am currently involved in a systematic review of prevalence and frequency of anal sex practice within heterosexual populations. Our reviews of HIV transmission probabilities have highlighted the high risk associated with heterosexual anal sex; therefore we need better estimation of patterns of anal sex within heterosexual populations to estimate its role in driving HIV transmission and its potential role in obscuring the true impact of some interventions (for example, does it dilute the effectiveness of vaginal microbicides?).


My other main research interest remains maternal health within developing countries. I have been estimating the potential impact of interventions such as multivitamin polypills and expanded access to family planning facilities in terms of maternal deaths averted.


I am passionate about the need for effective science communication, especially the process of developing innovative ways to convey complex ideas to different audiences: other researchers, policy makers, funders, media and the general population. I am involved with the Wellcome Trust’s public engagement activities and carried out a placement at the BBC to learn more about science broadcasting.




Baggaley R, Gon G, Ali S, et al., 2024, Do current maternal health staffing and bed occupancy benchmarks work in practice? Results from a simulation model, Bmj Public Health, Vol:2, ISSN:2753-4294

Pan D, Sze S, Irizar P, et al., 2023, Are clinical outcomes from COVID-19 improving in ethnic minority groups?, Eclinicalmedicine, Vol:61

Baggaley RF, Nazareth J, Divall P, et al., 2023, National policies for delivering tuberculosis, HIV and hepatitis B and C virus infection services for refugees and migrants among Member States of the WHO European Region, Journal of Travel Medicine, Vol:30, ISSN:1195-1982

Ho KMA, Baggaley RF, Stone TC, et al., 2023, Face Mask Acceptability for Communal Religious Worship During the COVID-19 Pandemic in the United Kingdom: Results from the CONFESS Study, Journal of Religion & Health, Vol:62, ISSN:0022-4197, Pages:608-626

White HA, Baggaley RF, Okhai H, et al., 2022, The impact, effectiveness and outcomes of targeted screening thresholds for programmatic latent tuberculosis infection testing in HIV, Aids, Vol:36, ISSN:0269-9370, Pages:2035-2044

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