Examining vulnerability to foodborne illness: A comprehensive review of “clinically vulnerable groups"

The consolidated findings have been scrutinised during three expert panel consultations to consider clinically vulnerable groups; these discussions helped inform the recommendations arising from this report. Therefore, the key recommendations acknowledge that:

• Ageing population needs to be broken down into categories according to conditions or medications. For example, GI conditions that require medications, chronic inflammatory diseases such as diabetes, cancers, and others.
• We defined susceptibility to foodborne illness among PPI users and provided a summary of data that demonstrated high prevalence of foodborne illness among PPI users. Furthermore, we determined that PPI users are neglected as a clinically vulnerable group in global definitions. Consequently, due to this compelling evidence, we recommend that PPI users should be addressed as a vulnerable population due to the demonstrated risk of foodborne illness among this group.
• From our research, most prevalence data linked to vulnerable populations comes from Listeria surveillance studies. Therefore, there is a lack of surveillance data to explore the merit of having pathogen-based definitions of clinically vulnerable groups, other than for Listeria. Future surveillance needs to capture data according to the clinically vulnerable groups to understand comorbidities for foodborne illness.
• More information needs to be captured detailing underlying conditions in patients with foodborne illnesses. Furthermore, to enable understanding of multimorbidity contributions to the risk of foodborne illnesses, it is necessary to enhance coding protocols in healthcare.
• Age cut-offs for young children and older adults are not solely based on immunological vulnerabilities, rather they reflect the period during the lifespan when an individual is more likely to develop certain comorbidities that would contribute to their susceptibility to foodborne illness. Due to high variability in individuals, and different perceptions among consumers, there is a need for further research to determine how cut-off age can be used most efficiently. Discussions with people aged ≥65 years established that grouped definitions (e.g. older adults) may result in consumer food safety messaging being ignored as the intended audience may not perceive that it is intended for them.
• Targeted communication is required for each clinically vulnerable group. Different levels of messaging complexity are required for consumers and healthcare providers. Research is required to explore healthcare professional perceptions regarding their role of communicating food safety to clinically vulnerable groups.
• While it was out of the scope of this review, we acknowledge that socio-demographic and behavioural factors also contribute to the risk of foodborne illnesses, therefore we recommend that further research is required to explore their contributions to susceptibility among clinically vulnerable groups. This may support further targeted communication approaches.
• It is acknowledged that public health agencies in different countries post annual foodborne disease reports on their websites and may not necessarily publish or index in electronic databases, therefore such reports require researchers to access these individually and require prior knowledge of their availability and location as such report are omitted when undertaking a systematic search. Therefore, for maximum utility, we recommend that public health agencies or food safety organisations attempt to peer-review and publish their annual reports on foodborne disease prevalence.

As a result of this work, we have identified several knowledge gaps that warrant future research. Specifically, consumer perceptions regarding food safety messaging for clinically vulnerable groups remain poorly understood. To facilitate the development of effective consumer food safety communication, research should focus on elucidating their awareness of food safety risks, preferred level of detail, acceptability of content and layout of materials. Our research highlights that PPI users stand out as a group that has been neglected in food safety communication. Prioritising consumer food safety research on this group is recommended. Additionally, a better understanding of the ageing population is necessary for targeted food safety messaging. The ageing population comprises of multiple clinically vulnerable groups, based on multiple generations and various co-morbidities, this also includes numerous behavioural and lifestyle factors. Further research should aim to discern the most appropriate categorisation for this diverse adult population, focusing on the consumer preference and perceptions.

Furthermore, healthcare professionals and social care providers play a critical role in providing trusted information and support to patients. However, there is limited understanding of their perceptions, attitudes, and preparedness to offer food safety advice to vulnerable patients. To effectively leverage opportunities in healthcare for improving food safety and wellness among clinically vulnerable groups, more evidence is needed regarding existing food safety training and education mechanisms for healthcare professionals. Such data will enable the development of tailored communication strategies for healthcare professionals and care providers.