Dr Stephen Parnell

Associate Professor

email: stephen.parnell@warwick.ac.uk

phone: 024 765 75192

Office (W): PPB 1.29

Twitter: @parnells

Research Clusters

Plant & Agricultural Biosciences

Microbiology & Infectious Diseases

Quantitative, Systems & Engineering Biology

Warwick Centres and GRPs

Zeeman Institute

Vacancies and Opportunities

For PhD and postdoctoral opportunities, and interest in potential collaborations, please contact me at the above email address.

Research Interests

I am a plant disease epidemiologist and modeller based at the Warwick Crop Centre and Zeeman Institute for infectious disease epidemiology.

Epidemics of plant destroying pests and diseases are on the rise due to the ever-increasing movement of people and plants around the planet. These pests and diseases can destroy plants in natural environments, such as forests, or in agricultural crops, impacting our ability to produce food.

We develop mathematical and computer models of how these pests and diseases spread through plant populations and use the models to test out strategies to detect and control them.

Research: Technical Summary

We use a range of epidemiological models, linked with data, to better understand the processes that determine the invasion and spread of plant pathogens and insect pest populations. Models range from systems of ODEs to stochastic spatially-explicit simulation models. A key practical focus is the optimisation of strategies for the detection and control of epidemics. Recent pests and diseases of focus include Ash dieback disease, Emerald Ash Borer, and Xylella fastidiosa in the horticultural trade.

Biography

Reader, School of Science Engineering and Environment, University of Salford (2014-2022)
Plant Health Panel Member, European Food Safety Authority (2014-present)
Senior Research Scientist, Rothamsted Research (2007-2014)
Postdoctoral Scientist, US Horticultural Research Laboratory, US Department of Agriculture, Florida (2005-2007)
Research Assistant, Rothamsted Research (2001-2002)
PhD Mathematical Biology, Department of Plant Sciences, University of Cambridge (2005)
BSc Ecological Science (Hons. Natural Resource Management), University of Edinburgh (2001)

Publications

Ellis, John, Lázaro, Elena, Duarte, Beatriz, Magalhães, Tomás, Duarte, Amílcar, Benhadi‐Marín, Jacinto, Pereira, José Alberto, Vicent, Antonio, Parnell, Stephen and Cunniffe, Nik J. (2025) Developing epidemiological preparedness for a plant disease invasion : modelling citrus huánglóngbìng in the European Union. Plants, People, Planet, 7 (5). pp. 1403-1423. doi:10.1002/ppp3.10643 ISSN 2572-2611.

Vincent, Elliot M. R., Hill, Edward M. and Parnell, Stephen (2025) Modelling the effectiveness of Integrated Pest Management strategies for the control of Septoria tritici blotch. PLoS Computational Biology, 21 (8). e1013352. doi:10.1371/journal.pcbi.1013352 ISSN 1553-7358.

Aschauer, Nadine and Parnell, Stephen (2025) Analysis of mathematical modelling approaches to capture human behaviour dynamics in agricultural pest and disease systems. Agricultural Systems, 226 . 104303. doi:10.1016/j.agsy.2025.104303 ISSN 0308-521X.

Alonso Chavez, V., Brown, N., van den Bosch, F., Parnell, Stephen, Dyke, A., Hall, C., Karlsdottir, B., Marzano, Mariella, Morris, J., O'Brien, Liz, Williams, D. and Milne, A. (2025) R : Early detection strategies for invading tree pests : targeted surveillance and stakeholder perspectives. Journal of Applied Ecology, 62 (4). pp. 857-871. doi:10.1111/1365-2664.70009 ISSN 0021-8901.

Alonso Chávez, Vasthi, Brown, Nathan, van den Bosch, Frank, Parnell, Stephen, Dyke, Alison, Hall, Clare, Karlsdottir, Berglind, Marzano, Mariella, Morris, Joanne, O'Brien, Liz, Williams, David and Milne, Alice E. (2025) Early detection strategies for invading tree pests : targeted surveillance and stakeholder perspectives. Journal of Applied Ecology, 62 (4). pp. 857-871. doi:10.1111/1365-2664.70009 ISSN 0021-8901.

Koh, Joshua, Cunnifee, Nik and Parnell, Stephen (2025) Assessing delimiting strategies to identify the infested zones of quarantine plant pests and diseases. Scientific Reports, 15 . 5610. doi:10.1038/s41598-025-90343-2 ISSN 2045-2322.

van Woensel, Eveline, van der Werf, Wopke, Parnell, Stephen, van Vliet, Arnold and Douma, Bob (J.C.) (2025) Exploring the contribution of citizen science to statistically sound and risk‐based surveillance of insect pests in the EU. EFSA Supporting Publications, 22 (2). 9186E. doi:10.2903/sp.efsa.2025.EN-9186 ISSN 23978325.

(EFSA), European Food Safety Authority, de la Peña, Eduardo, Dehnen-Schmutz, Katharina, Gilioli, Gianni, González-Moreno, Pablo, Makowski, David, Mastin, Alexander, Nougadère, Alexandre, Paracchini, Maria Luisa, Parnell, Stephen, Portaluri, Alessandro, Purse, Bethan, Ribaya, Maria, Sánchez, Berta, Scala, Marica, Tramontini, Sara and Vos, Sybren (2025) EFSA methodology for assessing candidate priority pests under EU Regulation 2016/2031. Parma. Italy: Wiley-Blackwell Publishing Ltd.. (efsa Supporting Publications).

Fielder, Hannah, Beale, Tim, Jeger, Michael J., Oliver, Gabriella, Parnell, Stephen, Szyniszewska, Anna M., Taylor, Philip and Cunniffe, Nik J. (2024) A synoptic review of plant disease epidemics and outbreaks published in 2022. Phytopathology®, 114 (8). pp. 1717-1732. doi:10.1094/PHYTO-01-24-0042-RVW ISSN 0031-949X.

Hill, Edward M., Ryan, Matthew, Haw, David, Lynch, Mark P., McCabe, Ruth, Milne, Alice E., Turner, Matthew S., Vedhara, Kavita, Zeng, Fanqi, Barons, Martine J., Nixon, Emily J., Parnell, Stephen and Bolton, Kirsty J. (2024) Integrating human behaviour and epidemiological modelling : unlocking the remaining challenges. Mathematics in Medical and Life Sciences, 1 (1). 2429479. doi:10.1080/29937574.2024.2429479 ISSN 2993-7574.

van den Bosch, Frank, McRoberts, Neil, Bourhis, Yoann, Parnell, Stephen and Hassall, Kirsty L. (2023) The value of volunteer surveillance for the early detection of biological invaders. Journal of Theoretical Biology, 560 . 111385. doi:10.1016/j.jtbi.2022.111385 ISSN 0022-5193.

Lovell-Read, Francesca A., Parnell, Stephen, Cunniffe, Nik J. and Thompson, Robin N. (2023) Using ‘sentinel’ plants to improve early detection of invasive plant pathogens. PLoS Computational Biology, 19 (2). e1010884. doi:10.1371/journal.pcbi.1010884 ISSN 1553-7358.

Mastin, Alexander J., van den Bosch, Frank, Bourhis, Yoann and Parnell, Stephen (2022) Epidemiologically-based strategies for the detection of emerging plant pathogens. Scientific Reports, 12 (1). 10972. doi:10.1038/s41598-022-13553-y ISSN 2045-2322.

Research Projects

Title	Funder	Award start	Award end
Warwick Research Sub-Grant agreement under WAVE Bridge: Next-WAVE for Sustainable Plant project. (Linked to 79663 Outline)	Bill & Melinda Gates Foundation	01 July 2024	30 November 2025
One Health Synthesis of Environmentally Sensitive Disease Preparedness Across Human, Animal and Plant Health	UK Research and Innovation	01 September 2024	31 May 2025
Quantifying variations in detection sensitivity and specificity for tree pests and diseases (DEFRA)	Department for Environment, Food and Rural Affairs	01 August 2024	31 March 2025
CONTRACT for the SUPPLY of Data Analysis and support for modelling project	Department for Environment, Food and Rural Affairs	01 May 2023	30 April 2024
'Experimental and observational evidence to reduce entomological knowledge gaps for plant health risk assessment and surveillance	Wageningen University	22 April 2022	24 April 2024
PREDICTIVE MODELLING TO DEVELOP PEST RISK ASSESSMENT. PRE-HLB Consortium ( Cambridge led)	European Commission	01 December 2022	30 November 2023
Dr Stephen Parnell - SMARTIES Novation Agreement - Surveillance and Management of multiple Risks to Treescapes: Integrating Epidemiology and Stakeholder behaviour	NERC	01 May 2022	30 November 2023
Survey planning tool - ongoing outbreaks (PI: Stephen Parnell)	Fera Science Limited	01 June 2022	31 July 2023
Defra Future Proofing Plant Health (FPPH) project led by Forest Research (for Dr Stephen Parnell)	Department for Environment, Food and Rural Affairs	02 June 2022	30 September 2022

Teaching / Student Supervision

I am happy to receive enquires about PG Research projects in my group, please contact me at the above email address.

Y3 undergraduate projects: I offer primarily desk-based projects using epidemiological data, models and/or questionnaires to understand the spread of plant disease epidemics and strategies for their detection and control.

Group Members

Current Members
Joshua Koh (PDRA)	Matt Combes (PDRA)