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

During the three expert panel consultations with the twenty experts (details of which can be seen in Appendix 4), the expert panel congratulated Food Standards Scotland on taking the initiative to commission this much needed work. They expressed their enthusiasm in having the opportunity to participate in the consultation and discuss the findings. The expert panel agreed that the research report merits publication and encouraged the publication of detailed reports specific to some of the clinically vulnerable groups identified in the report, particularly ageing adults, and other less acknowledged groups such as PPI users and people with IBD. The expert panel commended the rigour and comprehensiveness of the research and highlighted the significance and impact of the findings.

Several key themes arose from the discussions, these included considerations regarding neglected or emerging clinically vulnerable groups and recommendations for future surveillance, the roles and responsibilities of different stakeholders in communicating with clinically vulnerable groups, and recommendations for the future.

The experts indicated several categories of vulnerable patients that could be considered in future definitions. Patients suffering from long COVID was indicated as an emerging vulnerable population, and future surveillance should consider this group. PPI users should be addressed as a clinically vulnerable group as there is compelling evidence of increased foodborne illness risks. PPI prevalence is increasing in ageing adults, the experts considered if PPI users would consider themselves to be at risk. Furthermore, redefining the clinically vulnerable groups according to the specific medications, such as PPIs, immune suppressors, steroids, and others, rather than according to their age or conditions, was recommended as a more effective way of communicating to these groups.

In general, the lack of data was acknowledged for most foodborne pathogens, except for L. monocytogenes. The need for improved surveillance and the necessity to collect more information about the underlying conditions and the medications from patients was highlighted. It was suggested that linking foodborne illness data with medical records would give much needed insights to better understand the vulnerabilities relative to general populations.

More data is needed to better characterise the age groups both in the older adults and the children categories. The current cut-off ages remain a point of discussion among the experts. There was no consensus among the experts of specific age groups relating to children or ageing adults. However, it was acknowledged that current age groups reflect the categories that are used in epidemiological studies and/or retirement ages.

A gradient of vulnerability was suggested to describe the age-dependent changes. Immunological variations are individual and determined by co-morbidity and the use of medication that modify the susceptibility to foodborne illnesses.

The experts recommended future considerations of several sociodemographic and behavioural factors when developing future food safety definitions. Recommendations were also made for the research community to included low sociodemographic strata, ethnicity factors, immigrant and indigenous groups, and inclusion of developing regions in future reviews of prevalence data.

It was acknowledged that to provide meaningful data for FSS, the research excluded data from developing countries, however it was recommended that undertaking a similar review in developing countries was suggested to give a comparison between developed and developing countries. The potential impact of malnutrition upon susceptibility to foodborne illness could be explored in this work. In the current review, prevalence of foodborne illness among malnourished individuals were not obtained.

Experts acknowledged that all prevalence data that were associated with specific behavioural factors were excluded, however it was suggested that research is required to explore the potential impact of socio-economic and lifestyle factors upon the risk of foodborne illness. Food Standards Scotland have already recognised the importance of behavioural factors and with the Scottish Environment, Food and Agriculture Research Institutions, have funded a research fellowship to determine the lifestyle factors which cause particular members of the older population to become ill with foodborne disease (SEFARI, 2023).

Several emerging pathogens were mentioned including Hepatitis E and Vibrio spp., that could be considered in future work regarding clinically vulnerable groups.

The experts agreed that different versions of communication about vulnerabilities are needed for different groups. The majority thought that definitions by pathogen may not be efficient and could introduce more confusion especially for the consumers. A tiered approach with the most detailed technical information for health professionals was suggested.

While the experts highlighted the importance of understanding consumer perspectives, they thought that the simple summaries for the clinically vulnerable groups that emphasise the reasons for vulnerability and highlight the specific conditions and medications, rather than generalised information were thought to be more relatable to consumers and may potentially lead to improved food safety compliance. Explaining to the clinically vulnerable groups what the risks look like in practice, and clarifying that appropriate management of their conditions, such as diabetes and others, may lead to reducing their risk of foodborne infections. Offering alternative foods to high-risk options was recommended.

Responsibility in conveying information to clinically vulnerable groups was further discussed, and healthcare providers were identified as important sources of any information about food safety risks due to medication use. The patients would benefit if their medical doctors, or specialists explained the risks from foodborne pathogen infection if they are prescribed PPIs, immune suppressants, or steroids for their conditions.

The experts discussed the use of advanced and generative technology for food safety communication to clinically vulnerable groups and individuals. While they acknowledged technology may play an important role in the future, it was agreed that some clinically vulnerable groups remain reliant or simply prefer printed materials and simple digital messaging. 

Timing of food safety messaging to clinically vulnerable groups was brought up by the experts as both a challenge and an opportunity. Vulnerable patients would benefit the most from timely information delivered while they are in contact with the healthcare providers who are addressing their health conditions. This may present as a difficulty due to multiple other communications that the patients receive to help them through the healing and health management process. The patients may be overloaded with information and not open to food safety messages. The high workload among healthcare providers was also acknowledged as a challenge to adding the responsibility for food safety communication to their schedules. A multidisciplinary approach in which multiple healthcare professionals (e.g., doctors, nurses, dietitians, pharmacists, etc.) share the responsibility in delivering the consistent food safety information to the patients would ensure the awareness of the risks among clinically vulnerable groups.

During the expert panels, it was widely discussed that to enable a clear decision on the need for separate definitions for each of the pathogens of interest, there is a need for enhanced surveillance for Campylobacter, E. coli, Salmonella, and norovirus. It was suggested that there may be merit in having a distinct definition for listeriosis as more data are available in relation to prevalence of foodborne illness caused by L. monocytogenes among the clinically vulnerable groups. It was also suggested that having separate definitions per pathogen may be too confusing for consumers. For example, consumers may not need to know which foodborne pathogen they are at an increased risk of, they need to know that they are at an increased risk, the reasons why, and be aware of appropriate risk reducing behaviours.