VTEC/E. coli O157 Action Plan for Scotland, 2013-2017

IX. PROPOSALS FOR RESEARCH AND SURVEILLANCE

Despite the considerable resources that have been applied to research into VTEC, many gaps in our knowledge remain. The VTEC/E. coli O157 Action Group has identified areas in which further research is required to inform better evidence-based control measures. These include:

Chapters 1 and 2

RS1 - SG, in liaison with other relevant agencies, should regularly monitor developments in research efforts to identify practical and efficacious measures for controlling the excretion of VTEC from animals and feed back annually to the VTEC/E. coli O157 Action Group on any potentially useful control strategies.

Chapter 3

RS2 - SG should review available information on proportionate controls to reduce environmental contamination.

RS3 - SG should then consider resourcing, and where appropriate requiring, relevant agencies or groups to implement those any proportionate controls identified by their review on reducing environmental contamination (see Recommendation RS2 above).

RS4 - SG should feed back to the VTEC/E. coli O157 Action Group their review of proportionate control measures for reducing environmental contamination, and their conclusions on which (if any) agencies or groups should be resourced and/or required to implement them; and should ensure that simple national monitoring systems are established for each new control measure resulting from this review.

Chapters 6 and 7

RS5 - FSAS should consider funding research to improve understanding of the potential VTEC risks associated with unwashed and unpeeled fruit and vegetables on retail sale and the food safety implications of internalisation of VTEC by plants.

RS6 - HPS should consider research to investigate the contribution to VTEC infection in Scotland, of emerging food risks, including fresh produce and sprouted seeds.

RS7 - FSAS and LAs should ensure that surveillance of VTEC in foods is intelligence led and targeted to evaluating the effectiveness of controls applied to the production of foods which are a known VTEC risk.

RS8 - FSAS and LAs should ensure that food surveillance programmes include microbiological sampling at food premises producing 'at risk' RTE foods, to evaluate the effectiveness of cross contamination controls undertaken at butchers and catering businesses.

RS9 - FSAS - with input from SERL - should consider a review of laboratory provision in Scotland for the testing of E. coli and non-O157 VTEC strains in foodstuffs.

Chapter 9

RS10 - SG should commission research into ages of responsibility in children, and should report progress on this to the VTEC Action Group.

RS11 - HPS should consider a case control study to ascertain whether the aetiological fraction has changed since its previous study in 2001.

Chapters 11 and 12

RS12 - SG should consider commissioning a retrospective study to identify at what stage confirmed cases of E. coli O157 and non-O157 VTEC infection were suspected, and whether this was at an early enough stage to allow appropriate public health management.

RS13 - SG should consider commissioning a retrospective study to ascertain the dose and duration of excretion in cases who had been suspected and diagnosed early and treated appropriately (cases) compared to cases who had not (controls), and identify differences (if any) between E. coli O157 and non-O157 VTEC strains.

RS14 - SG should investigate the options for conducting occasional surveys of compliance with exclusion and other infection control guidance e.g. by front line NHS staff, HPTs or LAs, or via special studies of confirmed cases e.g. of nurseries, care homes, etc.

RS15 - HPS should consider options for research on pre-symptomatic exclusion, for instance whether it is possible to identify any differences in the risk of transmission from infected but asymptomatic individuals, depending on whether or not:

(a) They subsequently develop symptoms.
(b) The period of asymptomatic excretion occurred before their onset of symptoms, or after their own symptoms resolved (in those who become symptomatic at some point).
(c) Infection was due to E. coli O157 or non-O157 VTEC strains.

RS16 - SG should investigate options for sentinel or other surveillance of E. coli O157 and non-O157 VTEC in ruminants, to improve understanding of the strains circulating in ruminants, and to compare ruminant strains with those occurring in human cases.

RS17 - SG, SERL, HPS and other relevant agencies should consider how molecular epidemiology (including the use of Next Generation Sequencing) may improve understanding of relationships between
E. coli O157 and non-O157 VTEC strains from ruminants, humans, water, the environment and the foodchain.