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The edible part of a snail is the ‘foot’ commonly termed snail meat. It contains high-quality protein, low fat, high calcium, magnesium, iron, and little or no cholesterol. Researchers believe that a continuous consumption of snail meat could support healthy immune systems, thus, preventing acute to severe health conditions such as obesity, type 2 diabetes, cardiovascular diseases, and certain cancers. People are becoming informed of these health benefits and their consumption of snail meat is gradually increasing especially in many communities in Africa and Europe. However, snail farming or heliciculture is still under-developed around the world. Snail-consuming populations have often picked land snails from locations that include, swamps, forests, gardens, footpaths, farmlands, household wastes, stones, and logs of wood or termed ‘anywhere’. The close association of land snails with the soil and decaying vegetation, coupled with its uncontrolled free-living and feeding patterns, could make them susceptible to microbial contamination. Consequently, humans could easily get exposed to foodborne pathogens in these ‘snail picking’ locations or during the handling and/or consumption of snail meat. The aim of this PhD thesis was to understand foodborne disease health risks in the handling and/or consumption of snail meat, which is currently a desirable source of food among rural communities in sub-Saharan Africa. Specifically, this research focused on land or terrestrial snails where I sought to 1) explore human foodborne pathogen exposures in snail handling and/or consumption practices, 2) determine the prevalence of potential foodborne pathogens (Shigatoxigenic E. coli (STEC), Campylobacter spp., Salmonella spp., Listeria spp., and Yersinia spp.) in edible land snails collected from different natural habitats (farms and within dwellings) and local markets, and 3) evaluate the survival characteristics of STEC and non-STEC strains in the faeces of edible land snails. To achieve these research objectives, a methodological framework was developed (in Chapter 1), and the results are organized in three results chapters (Chapter 2, 3 & 4), using peer-reviewed journal formats. In Chapter 2, a field work-based study is described. It was conducted in Buea (Cameroon) where in-depth face-to-face interviews, participant observation, and focus group discussions were used to explore participant lived experience, stories, perceptions, habits, and routines that may involve human foodborne pathogens exposures in local snail consumption practices. Two theoretical frameworks; soft systems methodology and social practice theory were used to interpret the study findings. In our analysis from this research study area (Buea), several opportunities for human exposure to foodborne pathogens were apparent such as, snail picking in domestic wastes and sewage, the selling of unpackaged live snails, improper snail meat washing and hawking in loosely closed buckets. In Chapter 3, we examine the faeces of live edible African land snails, sampled within the same population described in Chapter 2, for the presence of Shiga-toxin producing Escherichia coli (STEC), Campylobacter spp., Salmonella spp., Listeria spp., and Yersinia spp. Experiments were conducted using high-fidelity DNA polymerase (repliQa Hifi toughmix: Quantabio, MA, USA) in single PCR techniques. The presence of an amplicon of the appropriate size for each PCR assay in each sample was recorded as a positive result. For STEC, a positive result required the detection of both Stx1 and Stx2 genes. The results showed that land snails from the study area contain high prevalence (57-86%) of STEC, Campylobacter spp., Salmonella spp., Listeria spp., and Yersinia spp. Indeed, at least one pathogen was detected in every sample examined, highlighting the threat of foodborne disease. Lastly, in Chapter 4, we examine the transmission dynamics and survival of pathogens in snails. A model system was established and used to explore the proliferation and survival of E. coli (STEC/non-STEC) strains. Well-studied STEC and non-STEC strains in the faeces of E. coli-inoculated land snails, which had been grown in a laboratory model system, were compared using plate counting method. Colonies were visually enumerated and expressed as a logarithmic function of colony forming units over 30 days of the experiment. In this system, the average rate of decline of non-STEC strain (CSH-62) in the faeces of live snails was significantly (p

Beef lungs are an underutilised co-product of the meat industry that could be used as an ingredient to supplement the protein content of cereal foods. Incorporating beef lung into widely consumed food can improve the protein quality of the food chain. Air oven drying was used to convert raw beef lungs to beef lung powder (BLP). Beef lungs were dried at 60˚C for 32 hours and ground into beef lung powder (BLP). BLP was incorporated into the pasta as a model food for delivery of macro and micronutrients. BLP had 87% protein content (dry weight basis) with a rich essential amino acid profile and contained 1 mg/g iron. Fresh semolina pasta was used as a model food, and BLP could be incorporated at up to 20% based on preliminary trials. Incorporation of 10% BLP improved the indispensable amino acid score (IAAS) of the pasta from 0.48 to 0.91, Pasta with 10% BLP showed better textural, colour and cooking characteristics compared to those where BLP was incorporated at 15% and 20% (P