Francis is based at East Malling in the pest and pathogen ecology department at NIAB EMR.  Research interests include Insect-plant and insect-virus interactions and insect pathogen discovery and molecular diagnostics.  Research interests are disrupting insect-mediated damage and transmission of plant pathogens and detecting pathogens in insect and plant hosts. Francis has worked quite extensively on understanding how insect (aphid) foraging, feeding and settling behaviour is manipulated by the presence of plant viruses and how this contributes to increased transmission of plant pathogens. Recently, Francis' work has focused on insect-infecting viruses and their potential use as environmentally friendly biocontrol and disruption of insect vectoring of viral pathogens. To detect pathogens in insects and plants, Francis has extensively used high-throughput sequencing and developed molecular detection tools for accurate and speedy detection of bacterial and viral pathogens.