In Japan, strategies for ensuring food safety have been developed without reliable scientific evidence on the relationship between foodborne diseases and food sources. This study aimed to provide information on the proportions of foodborne diseases caused by seven major causative pathogens (Campylobacter spp., Salmonella, enterohemorrhagic Escherichia coli [EHEC], Vibrio parahaemolyticus, Clostridium perfringens, Staphylococcus aureus, and norovirus) attributed to foods and to explore factors affecting changes in these source attribution proportions over time using analysis of outbreak surveillance data. For the calculation of the number of outbreaks attributed to each source, simple-food outbreaks were assigned to the single-food category in question, and complex-food outbreaks were classified under each category proportional to the estimated probability. During 2007 to 2018, 8,730 outbreaks of foodborne diseases caused by seven pathogens were reported, of which 6,690 (76.6%) were of unknown source. We estimated the following source attribution proportions of foodborne diseases: chicken products (80.3%, 95% uncertainty interval [UI] 80.1 to 80.4) for Campylobacter spp.; beef products (50.1%, UI 47.0 to 51.5) and vegetables (42.3%, UI 40.9 to 45.5) for EHEC; eggs (34.6%, UI 27.8 to 41.4) and vegetables (34.4%, UI 27.8 to 40.8) for Salmonella; finfish (50.3%, UI 33.3 to 66.7) and shellfish (49.7%, UI 33.3 to 66.7) for V. parahaemolyticus; grains and beans (57.8%, UI 49.7 to 64.9) for S. aureus; vegetables (63.6%, UI 48.5 to 74.6), chicken products (12.7%, UI 4.6 to 21.5), and beef products (11.1%, UI 8.5 to 13.1) for C. perfringens; and shellfish (75.5%, UI 74.7 to 76.2) for norovirus. In this study, we provide the best available evidence-based information to evaluate the link between foodborne diseases and foods. Our results on source attribution for Campylobacter spp. and EHEC suggest that the strict health regulations for raw beef were reflected in the proportions of these diseases attributed to this food.

To determine the efficacy of electrolysed oxidizing (EO) water in inactivating Vibrio parahaemolyticus on kitchen cutting boards and food contact surfaces. Cutting boards (bamboo, wood and plastic) and food contact surfaces (stainless steel and glazed ceramic tile) were inoculated with V. parahaemolyticus. Viable cells of V. parahaemolyticus were detected on all cutting boards and food contact surfaces after 10 and 30 min, respectively, at room temperatures. Soaking inoculated food contact surfaces and cutting boards in distilled water for 1 and 3 min, respectively, resulted in various reductions of V. parahaemolyticus, but failed to remove the organism completely from surfaces. However, the treatment of EO water [pH 2·7, chlorine 40 ppm, oxidation-reduction potential 1151 mV] for 30, 45, and 60 s, completely inactivated V. parahaemolyticus on stainless steel, ceramic tile, and plastic cutting boards, respectively. EO water could be used as a disinfecting agent for inactivating V. parahaemolyticus on plastic and wood cutting boards and food contact surfaces. Rinsing the food contact surfaces with EO water or soaking cutting boards in EO water for up to 5 min could be a simple strategy to reduce cross-contamination of V. parahaemolyticus during food preparation.

Global climate change is expected to have multiple impacts on food and water safety. Knowledge synthesis methods can provide a credible and robust assessment of the evidence on these potential impacts to inform risk assessments. To illustrate the utility of these methods to synthesize data for a case study scenario of one of the potential impacts of climate change on food safety, and to inform a complementary risk assessment model, we conducted a systematic review of the effects of water temperature and salinity on Vibrio parahaemolyticus in raw oysters and harvest waters. We searched four bibliographic databases for literature then two independent reviewers screened 953 citations for relevance and extracted data from 120 relevant articles. Sufficient data for meta-analysis were provided in 19 articles. Random-effects meta-analysis, a quality-of-evidence assessment, and meta-regression (where applicable) were conducted on unique data subsets reporting correlation coefficients for the relationships of interest. A positive correlation was identified between water temperature and V. parahaemolyticus in oysters (r=0.58; 95% CI: 0.47 to 0.68) and water (r=0.60; 95% CI: 0.47 to 0.70). However, both analyses were significantly heterogeneous (I2=74% and I2=75%, respectively), which was not explained by the variables evaluated in meta-regression. No consistent relationship was identified for water salinity. A low and very low quality-of-evidence was identified for the water temperature and salinity relationships, irrespective of sampling media. Due to insufficient reporting and availability, we were unable to perform meta-analysis on regression coefficients for direct inclusion in the risk assessment model. However, the synthesis process provided a structured and transparent evaluation of the evidence to confirm associations between water temperature and V. parahaemolyticus densities, indicate no consistent association between salinity and V. parahaemolyticus densities, and compile available regression coefficients. Future synthesis research could evaluate other effects of climate on food and water safety to inform additional risk assessments.