Current Research Topics

Vaccine epidemiology

We research the epidemiology of infectious diseases and vaccines, with expertise in math modelling, statistics, clinical trial design and genomics. We are interested in how vaccine efficacy and effectiveness is measured, the impact of vaccination on disease dynamics and optimal vaccination strategies. We have over 15 years’ experience working on the epidemiology of vaccines, including those against polio, typhoid, rotavirus diarrhoea, and COVID-19.

Recent vaccine epidemiology publications

See group members personal webpages for the most up to date publications.

Candido, D. d. S., S. Dellicour, L. V. Cooper, C. A. Prete, D. Jorgensen, C. B. Uzzell, A. Voorman, H. Lyons, D. Klapsa, M. Majumdar, K. Arowolo, C. M. Peak, A. S. Bandyopadhyay, J. Martin, N. C. Grassly and I. M. Blake (2025). "Historical and current spatiotemporal patterns of wild and vaccine-derived poliovirus spread." Nature Microbiology 10(12): 3148-3161. https://doi.org/10.1038/s41564-025-02174-6

Jorgensen, D., M. Pons-Salort, M. Salman, A. Khurshid, Y. Arshad, N. Mahmood, D. da Silva Candido, S. Kroiss, H. Lyons, N. C. Grassly and M. M. Alam. 2025. Evolution and transmission dynamics of wild poliovirus in Pakistan and Afghanistan (2012-2023). Nat Commun 16: 5170. https://doi.org/10.1038/s41467-025-60432-x

Cooper LV, Erbeto TB, Danzomo AA, Abhullahi HW, Boateng K, Adamu US, Shuaib F, Modjirom N, Gray EJ, Bandyopadhyay AS, Zipursky S, Okiror S O, Grassly NC, Blake IM. 2024. Effectiveness of poliovirus vaccines against circulating vaccine-derived type 2 poliomyelitis in Nigeria between 2017 and 2022: a case-control study. Lancet Infect Dis https://doi.org/10.1016/S1473-3099(23)00688-6 

Gray, E. J., L. V. Cooper, A. S. Bandyopadhyay, I. M. Blake and N. C. Grassly. 2023. The origins and risk factors for serotype-2 vaccine-derived poliovirus emergences in Africa during 2016–2019. J Infect Dis: jiad004. https://doi.org/10.1093/infdis/jiad004

Disease surveillance and genomics

We research novel approaches to infectious disease surveillance, including the use of serological surveys, environmental (wastewater) surveillance and next-generation (nanopore) sequencing. We have developed a novel method for poliovirus detection and sequencing (DDNS; https://polionanopore.org), which is being implemented in multiple countries globally and used to accelerate poliovirus detection and outbreak response. We also lead consortia investigating wastewater surveillance for pandemic prevention (https://www.waspp.org), typhoid (https://www.typhoides.org), and other pathogens, in close collaboration with research partners around the world. This work includes development of new laboratory methods together with appropriate downstream analyses to inform decisions on public health action and the design of efficient surveillance systems.

Recent surveillance and genomics publications

See group members personal webpages for the most up to date publications.

Grassly, N. C., A. G. Shaw and M. Owusu. 2024. Global wastewater surveillance for pathogens with pandemic potential: opportunities and challenges. Lancet Microbe: 100939. https://doi.org/10.1016/j.lanmic.2024.07.002

Jorgensen, D., N. C. Grassly and M. Pons-Salort. 2024. Global age-stratified seroprevalence of enterovirus D68: a systematic literature review. Lancet Microbe: 100938. https://www.dx.doi.org/10.1016/j.lanmic.2024.07.001

Uzzell CB, Abraham D, Rigby J, Troman CM, Nair S, Elviss N, Kathiresan L, Srinivasan R, Balaji V, Zhou NA, Meschke JS, John J, Kang G, Feasey N, Mohan VR, Grassly NC. 2023. Environmental surveillance for Salmonella Typhi and its association with typhoid fever incidence in India and Malawi. J Infect Dis https://doi.org/10.1093/infdis/jiad427

Shaw AGG, Mampuela TK, Lofiko EL, Pratt C, Troman C, Bujaki E, O'Toole A, Akello JO, Aziza AA, Lusamaki EK, Makangara JC, Akonga M, Lay Y, Nsunda B, White B, Jorgensen D, Pukuta E, Riziki Y, Rankin KEE, Rambaut A, Ahuka-Mundeke S, Muyembe J-J, Martin J, Grassly NC, Mbala-Kingebeni P. 2023. Sensitive poliovirus detection using nested PCR and nanopore sequencing: a prospective validation study. Nat Microbiol 8: 1634-1640.

Rogawski McQuade ET, Blake IM, Brennhofer SA, et al. Real-time sewage surveillance for SARS-CoV-2 in Dhaka, Bangladesh versus clinical COVID-19 surveillance: a longitudinal environmental surveillance study (December, 2019-December, 2021). Lancet Microbe 2023; 4(6): e442-e51. https://doi.org/10.1016/S2666-5247(23)00010-1

Pons-Salort M, Lambert B, Kamau E, Pebody R, Harvala H, Simmonds P and Grassly NC. 2023. Changes in transmission of Enterovirus D68 (EV-D68) in England inferred from seroprevalence data., eLife https://doi.org/10.7554/eLife.76609

Immune correlates of protection by vaccination

We investigate factors affecting the immune response to vaccination and immune correlates of protection (CoP) following vaccination. This work is focused particularly on the mucosal immune response to oral and injected rotavirus and poliovirus vaccines and protection against challenge with live-attenuated vaccine virus.

Recent vaccination publications

See group members personal webpages for the most up to date publications.

Chirwa, M.,  Simuyandi, M., Phiri, B., Chibuye, M., Laban, N., Muzazu, S., Munyinda, M. Khatanga, S., Silwamba, S., Chauwa, A., Sukwa, N., Chisenga, C., Bosompraph, S., Chilengi, R. and Grassly, N. 2026. Safety and Reactogenicity of Heterologous Prime-Boost with Oral and Parenteral Rotavirus Vaccines: a randomized controlled trial among Zambian children. http://dx.doi.org/10.2139/ssrn.6027686

Williams, L. R., M. Voysey, A. J. Pollard and N. C. Grassly. 2025 A statistical method for evaluating vaccine-induced immune correlates of protection against infection and disease progression: application to the ChAdOx1-S nCoV-19 phase 3 trial. Vaccine 67: 127856. https://doi.org/10.1016/j.vaccine.2025.127856

Grassly NC, Andrews N, Cooper G, Stephens L, Waight P, Jones CE, Heath PT, Calvert A, Southern J, Martin J, Miller E. 2023. Effect of maternal immunisation with multivalent vaccines containing inactivated poliovirus vaccine (IPV) on infant IPV immune response: A phase 4, multi-centre randomised trial. Vaccine 41: 1299-1302.

Research culture

We are a diverse and inclusive research group. We implement a recruitment process that focuses on potential and values as well as experience, so that excellence and inclusion go hand in hand. We encourage and support development opportunities for all our members and foster an inclusive environment for growth, collaboration and high impact science. We also actively participate in the School of Public Health’s People & Culture Committee . We collaborate with researchers from the communities and geographies most impacted by the diseases we study, ensuring our work is fit for purpose. Our work is only as robust as the perspectives behind it, and we believe that a diversity of backgrounds leads to a diversity of thought.

Publication

Christen, P., J. Michalow, T. Naidoo, H. Topazian, S. L. van Elsland, A. M. Arif, M. Baguelin, G. Clunie, S. Essilfie-Quaye, D. Fecht, T. Garske, S. Hassounah, J. Husbands, W. Kwok, S. Leuba, C. McCormack, K. M. Mitchell, M. Pianella, M. Pickles, S. N. Ruybal-Pesántez, N. Schmit, C. Udeh-Momoh, A. Cori, I. Blake and L. C. Okell. 2025. Examining gender and ethnic disparities in scientific authorship to promote a culture of equity, diversity and inclusion at a university school of public health. Proc Roy Soc B: 292(2059). https://doi.org/10.1098/rspb.2025.0313