Paul McMenemy – Norovirus – A Case Study 1 st Year PhD Student – Paul McMenemy(UoS) Primary Supervisor – Dr Adam Kleczkowski (UoS) Secondary Supervisor – Dr Frans de Vries (UoS) Industrial Supervisor – Dr Nick Taylor (CEFAS)

Paul McMenemy – News Headlines - Norovirus 2 Cases of the winter vomiting bug 'top a million – BBC, 28 th Dec 2012 New strain of norovirus spreads around the world – Yahoo News, 9 th Jan 2013 New strain of norovirus – Centre for Disease Control – USA, 14 th Jan 2013 New Mutant Norovirus Strain to Wreak Havoc on Cruise Industry? – cruiselawnews.com, 16 th Jan 2013 GII.4 Sydney strain – nicknamed Down Ch-under Worldwide impact of new and existing virus strains Becoming more prevalent in 21 st century

Paul McMenemy – What is Norovirus? Small round structured virus (SRSV) Worlds main cause of gastroenteritis Transmitted via the faecal-oral route – Eat/drink contaminated foodstuffs – Touch contaminated surfaces then put fingers in your mouth – Contact with someone who is infected Many different strains of norovirus(NoV) – Person can be infected multiple times Symptoms – Diarrhoea – Vomiting, Nausea – Stomach pain 3 (Sources – ) -Fever -Headache -Body aches

Paul McMenemy – Reduce NoV in oysters : Reduce NoV outbreaks Norovirus in Shellfish Industry 4 Main cause - sewage treatment works Prevalent in most bivalves Cooking shellfish kills NoV Oysters eaten raw in U.K.

Paul McMenemy – U.K. Oyster Supply Chain 5 Harvest Wholesale Imports Retail Consumer Depuration Initial focus of study

Paul McMenemy – Depuration Stage Oysters are flushed with clean water Reduces bacterial contaminants (E. coli) Limited impact on virus counts in oysters More straightforward to model than other stages Costly to depurate Can reduce oyster quality 6

Paul McMenemy – Probability Distribution Model – Depuration Stage 7 Use existing pre-depuration data (courtesy - – Existing data split for genome types I and II – Find NoV count per oyster distribution function

Paul McMenemy – Probability Distribution Model – Depuration Stage 8

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Paul McMenemy – Uses of Model 11

Paul McMenemy – Further Work Model v Experimental Data : – Data on NoV count before and after depuration needed to validate and fine-tune model Economic work on cost-benefit analysis Create models on other stages of supply chain – Wholesale/Retail (storage, testing) – Consumer (awareness, frequency of consumption) 12

Paul McMenemy – Thank you for listening… Impact Collaborative Studentship funded by: The University of Stirling and Centre for Environment, Fisheries & Aquaculture Science 13