Spence was a scientific researcher in plant virology at Horticulture Research International and Fera. She has researched viral diseases of crops and horticulture both in Africa and the UK. Her research into viral diseases of crops in Africa has included investigations into the pathogenicity of bean common mosaic virus and its occurrence in legumes in Uganda. She has also published on the economic impact of turnip mosaic virus, cauliflower mosaic virus and beet mosaic virus in Kenya and patterns of plant pest introductions into Europe and Africa. She was the vegetables technical advisor for the Department for International Development's crop protection programme, leading projects on management of viral diseases in vegetable crops in Kenya and promotion of quality kale seed in Kenya. In UK horticultural systems, Spence has worked on identifying viruses present in Alstroemeria crops in the UK, as well as isolating and characterising viruses from petunia and Cineraria. Other research included studying the effect of pepino mosaic virus on tomato yield. She was an editor and contributor to the book Biotic Interactions in Plant-pathogen Associations. and she was previously a member of the Editorial Board for the scientific journalPlant Pathology. Spence was appointed Chief Scientist at Fera in 2009.
In 2009 Spence was appointed the chief executive of Science CityYork, later known as SCY, an organisation supporting the development of science and technology industries in York, England. In this role, Spence promoted connections between academics and local businesses, managing events such as Venturefest. She was key in the development of the concept of the BioVale, which aims to promote the bioeconomy in Yorkshire and the Humber. She remained in the role for four years, until her appointment as Chief Plant Health Officer.
Chief Plant Health Officer
Spence took up her post as Chief Plant Health Officer in April 2014, and later also became Deputy Director for Plant and Bee Health. Spence has made several media appearances in relation to her work at Defra. In April 2016 she appeared on the Today Programme to discuss the finding of a resistant ash tree in Norfolk, and has also appeared on the BBC's Countryfile programme. She has also been a guest on Farming Today discussing tree diseases in the UK. In 2016, she was involved in the management of the Asian hornet outbreak response, and appeared on the World at One to explain Asian hornet biology and the Defra response to the outbreak. In 2017, in response to the Xylella fastidiosa outbreak in several European countries, Spence wrote to the horticulture sector urging them to follow the example of those which had committed not to bring inhost plants from the affected countries. In 2018, she was a guest and speaker at summit examining the risks posed by Xylella to the horticulture industry hosted by Prince Charles. In May 2018, Spence gave evidence to the EU Select Committee on Brexit and the potential implications for plant health. Whilst at Defra, Spence has been active in promoting plant health as a career. In conjunction with the Royal Society of Biology and Charles Lane at Fera Science, Spence developed the Plant Health Professional Register – a way for those working in the area of plant health to gain a formal recognition of their professional skills and continue their professional development. She worked with Harper Adams University to put together a course on plant biosecurity, and is a visiting professor at the university.
