I am a clinician and epidemiologist with an interests in infectious diseases and vaccinology. I trained in Infectious Diseases in London and Newcastle and in Epidemiology at LSHTM. Since 1993 I have worked almost continuously at the KEMRI-Wellcome Trust Research Programme in Kilifi, Kenya both as researcher and clinician. Between 1998-1999 I spent two years at the Respiratory Diseases Branch of the US CDC in Atlanta. Between 1998 and 2012 I was based at the Nuffield Department of Clinical Medicine in Oxford; since 2013 I have been based at the School. Since 2016 I have been supporting the development of a new research centre, the Hararghe Health Research partnership, in Harar, Ethiopia - a collaboration between LSHTM and Haramaya University. I have directed the NIHR Health Protection Research Unit in Immunisation since 2014 and, from 2013-2023, I was a member of the UK vaccine policy committee, JCVI. I continue to do vaccine policy work on the WHO strategic advisory group of experts in vaccines and immunisation.
Affiliations
Centres
Teaching
Each summer, since 2014, I have co-directed a two week intensive short course with Stefan Flasche under the title: "Epidemiological Evaluation of Vaccines: Efficacy, Safety and Policy". I lecture on infectious diseases, surveillance, disease burden assessment, pneumonia and pneumococcal diseases on a variety of MSc modules including Epidemiology of Infectious Diseases, Clinical Bacteriology and Vaccine Immunology.
Research
Since the early 1990s I have researched the aetiology of pneumonia in adults and children and the causes of death in children, with a focus on East Africa. I have measured the impact of new conjugate vaccines for H. influenzae type b and Pneumococcus against invasive bacterial disease, meningitis and pneumonia. I have used carriage studies and modelling to understand the transmission of pneumococci and the indirect effects of conjugate vaccines. I have also undertaken Phase I/II vaccine studies of new vaccines against pneumococcus and non-typhoidal salmonella and studied the immunogenicity of pneumococcal conjugate vaccines given to newborn children, and given in fractional doses to older children. In Eastern Ethiopia, I have described the causes of death in children aged <5 years and in Kenya I have followed the long term mortality impacts of new vaccines and the COVID-19 pandemic in the Kilifi HDSS. I have used seroepidemiological studies to define population immunity to pneumococcus and SARS-CoV-2. In the UK I have overseen a programme of policy-relevant research to assist JCVI, UKHSA and NHS England to introduce new vaccines and optimise existing vaccine programmes.