Table A.1.

Overview of EFSA Opinions where microbiological criteria are considered in relation to specific food/pathogen combinations

Title of scientific opinion (Year of publication, Reference)	Specific TOR related to microbiological criteria (FSC or PHC)	Assessment of impact on: (i) public health, (ii) product compliance	Approach used for the assessment	Answers to TOR (extracts from the Opinions)
Microbiological risks of infant formulae and follow‐on formulae (2004) (EFSA, 2004)	Identify the best control options, special attention should be paid to assessing the possible use of microbiological testing, through guidelines or standards, as well as measures applicable at the time of preparation and storage of these foods until their consumption	Assessment of impact on public health and product compliance was not performed	Based on epidemiological evidence	It is recommended that a Performance Objective (PO) for powdered infant formula and follow‐on formula, aiming at very low levels of Salmonella and E. sakazakii (e.g. absence in 1, 10 or 100 kg) is introduced and that verification of compliance with the PO is confirmed by testing for Enterobacteriaceae in the environment and in the product. …. In some situations, in order to ensure that a Performance Objective is reached, microbiological testing might be an option. In the case of E. sakazakii and Salmonella in infant formula, the introduction of a microbiological criterion for these specific pathogen organisms is not recommended.
Biological Hazards on Bacillus cereus and other Bacillus spp. in foodstuffs (2005) (EFSA, 2005)	List and evaluate specific control measures, including microbiological testing and temperature requirements, to manage the risk caused by Bacillus cereus, other Bacillus spp. and their toxins in foodstuffs	Assessment of impact on public health was performed	Based on epidemiological evidence	For the development of new food product, or food product that support growth of B. cereus, either by their nature or their conditions of storage (e.g. extended shelf life), processors should ensure that numbers of B. cereus between 103 and 105 per g are not reached at the stage of consumption under anticipated conditions of storage and handling. This should also apply for dehydrated foods reconstituted by hot water before consumption. The maximum limit at consumption described in the above bullet point should be used as a target for food business operators to verify their HACCP system and could be considered as microbiological criteria to test the acceptability of a process.
Updating the former SCVPH opinion on Listeria monocytogenes risk related to RTE foods and scientific advice on different levels of L. monocytogenes in RTE foods and the related risk for human illness (2008) (EFSA, 2008b)	To provide scientific advice on different levels of L. monocytogenes in ready‐to‐eat foods and the related risk for human illness	Assessment of impact on public health and product compliance was performed	Based on risk assessment (qualitative MRA) and epidemiological evidence	Microbiological criteria will assist in controlling the levels of L. monocytogenes, e.g. absence in 25 g or ≤100 CFU/g at the point of consumption. The most recent Codex document on microbiological criteria for L. monocytogenes in ready‐to‐eat foods suggests a zero tolerance throughout the shelf life of the product for ready‐to‐eat foods in which growth of this microorganism can occur. Applying this criterion throughout the shelf life may prevent consumption of ready‐to‐eat foods representing a high risk. However, applying this criterion close to the end of shelf life could classify products as unsatisfactory, although they are of low risk. An additional option proposed in this Codex document is therefore to tolerate 100 CFU/g throughout the shelf life provided that the manufacturer is able to demonstrate that the product will not exceed this limit throughout the shelf life. For ready‐to‐eat foods that support growth of L. monocytogenes, it is impossible to predict with high degree of certainty that the level will or will not exceed 100 CFU/g during the shelf life of these products. Thus, applying this option may result in accepting a probability that foods with more than 100 CFU/g will be consumed. The impact on public health would depend whether the levels markedly above 100 CFU/g are reached.
Risk based control of biogenic amine formation in fermented foods (2011) (EFSA BIOHAZ Panel, 2011b)	Characterise concentration levels of biogenic amine in relevant fermented foods that are not associated with adverse health effects of defined consumer groups including susceptible consumers	Assessment of impact on public health was performed	Based on risk assessment	Consumption data and the exposure assessment were used to define the concentrations in food that would be allowable; however, this will vary between individuals, regions and countries. No adverse health effects have been observed in healthy volunteers to a level of 25 to 50 mg of histamine per person per meal. This level may be occasionally exceeded by consumption of one or more food items containing high amounts of histamine during the same meal. Further research is needed on the evaluation of the need for and, if/where necessary, development of process hygiene criteria for histamine and tyramine in fermented foods, as well as food safety criteria for histamine in fermented foods other than fish.
Campylobacter in broiler meat production: control options and performance objectives and/or targets at different stages of the food chain (2011) (EFSA BIOHAZ Panel, 2011a)	To evaluate potential performance objectives and/or targets at different stages of the food chain in order to obtain, e.g. 50% and 90% reductions of the prevalence of human campylobacteriosis in the EU caused by broiler meat consumption	Assessment of impact on public health and product compliance was performed	Based on risk assessment	Compliance with microbiological criteria is effective to reduce risks for Campylobacter on broiler meat because of high within‐batch prevalence and low within‐batch variability enabling detection of highly contaminated batches even when taking a limited number of samples. They stimulate improved control of Campylobacter during slaughter. The public health benefits of setting microbiological criteria were evaluated using data from the 2008 EU baseline survey. These estimates are average values for the whole EU; the impact could be very different between MSs. Theoretically, a public health risk reduction > 50% at the EU level could be achieved if all batches that are sold as fresh meat would comply with microbiological criteria with a critical limit of 1000 CFU/gram of neck and breast skin. Theoretically, a public health risk reduction > 90% at the EU level could be achieved if all batches that are sold as fresh meat would comply with microbiological criteria with a critical limit of 500 CFU/gram of neck and breast skin.
Shiga toxin‐producing Escherichia coli and other pathogenic bacteria in seeds and sprouted seeds (2011) (EFSA BIOHAZ Panel, 2011b)	To recommend, if considered relevant, microbiological criteria for seeds and sprouted seeds, water and other material that may contaminate the seeds and sprouts throughout the production chain	Assessment of impact on public health was performed	Based on epidemiological evidence (outbreak data) and microbiological data	It is currently not possible to evaluate the extent of public health protection provided by specific microbiological criteria for seeds and sprouted seeds. This highlights the need for data collection to conduct quantitative risk assessment. Consideration should be given to the development of new or revision of the existing microbiological criteria for pathogens most frequently associated with outbreaks involving sprouts – Salmonella spp. and pathogenic E. coli. Currently, there are no criteria for pathogenic E. coli. If such criteria were to be proposed serotypes of concern and associated with severe human disease should be considered. Microbiological criteria for Salmonella, pathogenic E. coli and L. monocytogenes could be considered for seeds before the start of the production process, during sprouting and in the final product. During the industrial sprouting process testing spent irrigation water for pathogenic bacteria has been proposed as an alternative strategy to the analysis of a large number of sprout samples. However, there are some uncertainties regarding the sensitivity of this strategy. Sampling could be conducted on sprouted seed production environments. It could be applied for pathogenic bacteria such as L. monocytogenes as well as indicator bacteria. There are currently no indicator organisms that can effectively substitute for the testing of pathogens in seeds, sprouted seeds or irrigation water. Testing for E. coli, Enterobacteriaceae and Listeria spp. can inform process hygiene control. Further work may be required to assess the value of tests for these indicator organisms.
Update on the present knowledge on the occurrence and control of foodborne viruses (2011) (EFSA BIOHAZ Panel, 2011d)	To discuss the scientific reasons for and against the establishment of food safety criteria and process hygiene criteria for viruses for certain food categories (e.g. fresh produce, bivalve molluscs etc.).	Assessment of impact on public health and product compliance was not performed	Based on epidemiological evidence (outbreak data)	Microbiological criteria for HAV and NoV are useful for validation and verification of HACCP‐based processes and procedures, and can be used to communicate to food business operators what is an acceptable or unacceptable viral load. Regulation (EC) 2073/2005 indicates that criteria for pathogenic viruses in live bivalve molluscs should be established when the analytical methods are developed sufficiently. Furthermore, regulation (EC) No 853/200410 provides a possibility to lay down additional health standards for live bivalve molluscs including virus testing procedures, and virological standards. Assuming that quantitative data on viral load is available, it would be possible to establish criteria for NoV in bivalve molluscs, while considering the impact of a given criteria on the exposure of the consumer. Viruses can be detected in fresh produce, but prevalence studies are limited, and quantitative data on viral load is scarce making establishment of microbiological criteria for these food categories difficult. Although there are documented cases of derived illness, the relative contribution of fresh produce to the overall public health FBV risk has not been established.
Norovirus (NoV) in oysters: methods, limits and control options (2012) (EFSA BIOHAZ Panel, 2012a)	Limits that do not pose an unacceptable risk to consumers for NoV genogroups GI and GII in oysters as determined by real‐time PCR (e.g. copy number per gram)	Assessment of impact on public health and product compliance was performed	Based on exposure assessment	Compliance with any of the above NoV limits would reduce the number of contaminated oysters placed on the market and therefore the risk for consumers to become infected. The lower the limit the greater the consumer protection achieved. However, it is not currently possible to quantify the public health impact of establishment of different limits. Microbiological criteria for NoV in oysters are useful for validation and verification of HACCP‐based processes and procedures, and can be used to communicate to food business operators and other stakeholders what is an acceptable or unacceptable viral load for oysters to be placed on the market. Microbiological criteria for NoV in oysters could also be used by competent authorities as an additional control to improve risk management in production areas, during processing and retail. On the basis of the data presented in this Opinion, risk managers should consider establishing an acceptable limit for NoV in oysters to be harvested and placed on the market.
Risk posed by Salmonella and Norovirus in leafy greens (2014) (EFSA BIOHAZ Panel, 2014a)	To recommend, if considered relevant, microbiological criteria throughout the production chain	Assessment of impact on public health was performed	Based on epidemiological evidence (outbreak data)	The current legal framework does not include microbiological criteria applicable at the primary production stage. It is here proposed to define criteria to validate and verify Good Agricultural Practices (GAP) and Good Hygiene Practices (GHP). These criteria will be designated as Hygiene Criteria and are defined as criteria indicating the acceptable functioning at pre‐harvest, harvest and on farm post‐harvest production prior to processing. E. coli was identified as suitable for a Hygiene Criterion at primary production of leafy greens and could be considered for validation and verification of Good Agricultural Practices (GAP) and Good Hygiene Practices (GHP) and on the basis of this, growers should take appropriate corrective actions. A Process Hygiene Criterion for E. coli in leafy green packaging plants or fresh cutting plants will give an indication of the degree to which collectively GAP, GHP, GMP or HACCP programmes have been implemented. A Food Safety Criterion for Salmonella in leafy greens intended to be eaten raw as salads could be used as a tool to communicate to producers and processors that Salmonella should not be present in the product. Noroviruses can be detected in leafy greens, but prevalence studies are limited, and quantitative data on viral load are scarce making establishment of microbiological criteria for these foods difficult. Information is lacking on the relationships between the occurrence of Norovirus as detected by real time RT‐PCR, infectivity and the actual risk to public health.
Risk posed by Salmonella and Norovirus in berries (2014) (EFSA BIOHAZ Panel, 2014b)	To recommend, if considered relevant, microbiological criteria throughout the production chain	Assessment of impact on public health was performed	Based on epidemiological evidence (outbreak data)	It is currently not possible to assess the suitability of an EU‐wide E. coli Hygiene Criterion at primary production for berries. However, using E. coli as an indicator of recent human or animal faecal contamination is likely to be useful for verification of GAP and GHP when applied to berries in individual production sites. It is currently not possible to assess the suitability of an EU‐wide Norovirus Hygiene Criterion at primary production for raspberries and strawberries, but this should be considered for the future, as well as for other berry fruits if additional public health risks are identified. Currently, there are no Process Hygiene criteria covering whole frozen berries and for these products there are no available data on occurrence of E. coli or Salmonella. It is therefore not possible to assess the suitability of an EU‐wide E. coli Process Hygiene Criterion for whole frozen berries. However, using E. coli as an indicator for verification of GMP and food safety management systems (including HACCP) might be useful for frozen berries in individual processing premises. Microbiological criteria for Norovirus in berries are useful for validation and verification of food safety management systems, including HACCP‐based processes and procedures, and can be used to communicate to food business operators and other stakeholders what is acceptable or unacceptable viral load for berries to be placed on the market It is currently not possible to provide a risk base for establishing a Process Hygiene Criterion for these foods. However, on the basis of the emerging public health risk, the collection of appropriate data and subsequent development of a Norovirus Process Hygiene Criterion for frozen raspberries and strawberries should be considered as a priority. On the basis of public health risk, there is currently insufficient evidence to justify the establishment of a Food Safety Criterion for Salmonella for fresh and minimally processed berries (including frozen berries). It is currently not possible to provide a risk base for establishing a Norovirus Food Safety Criterion for these foods.
Risk posed by Salmonella and Norovirus in tomatoes (2014) (EFSA BIOHAZ Panel, 2014c)	To recommend, if considered relevant, microbiological criteria throughout the production chain.	Assessment of impact on public health was performed	Based on epidemiological evidence (outbreak data)	The current lack of data does not allow the proposal of a Hygiene Criterion for E. coli at primary production of tomatoes. There is insufficient information available on the occurrence and levels of E. coli in pre‐cut, mashed and other minimally processed tomatoes and therefore the suitability of this criterion cannot be assessed. For this reason, it is therefore not possible to assess the suitability of an EU‐wide E. coli Process Hygiene Criterion for these products. Using E. coli as an indicator for verification of GMP and food safety management systems (including HACCP) might be useful for tomatoes in individual processing premises. A Food Safety Criterion for Salmonella in whole tomatoes could be considered as a tool to communicate to producers and processors that Salmonella should not be present in the product. Testing of whole tomatoes for Salmonella could be limited to instances where other factors indicate breaches in GAP, GHP, GMP or HACCP programmes. Although Noroviruses have been detected in tomatoes, occurrence studies are limited, and quantitative data on viral load are scarce. For Norovirus, there is very limited occurrence data in the world‐wide literature and only one outbreak was reported in the EU between 2007 and 2012, due to a (vomiting) food handler during buffet preparation in catering, thus it is currently not possible to provide a risk base for establishing a Food Safety Criterion for these foods.
Risk posed by Salmonella in melons (2014) (EFSA BIOHAZ Panel, 2014d)	To recommend, if considered relevant, microbiological criteria throughout the production chain	Assessment of impact on public health was performed	Epidemiological evidence (outbreak data)	There are limited studies available on the presence and levels of enteric bacteria such as E. coli on melons and watermelons and therefore it is currently not possible to assess the suitability of an EU‐wide E. coli Hygiene Criterion at primary production. Using E. coli as an indicator of recent human or animal faecal contamination is likely to be useful for verification of GAP and GHP at individual production sites. The existing Process Hygiene Criterion for E. coli in pre‐cut melons and watermelons aims to indicate the degree to which GAP, GHP, GMP or HACCP programmes have been implemented. There is insufficient information available on the occurrence and levels of E. coli in pre‐cut melons and watermelons and therefore the suitability of this criterion cannot be assessed. There are Food Safety Criteria for the absence of Salmonella in 25 g samples of ready‐to‐eat pre‐cut fruit and vegetables which is applicable to cut melon and watermelon placed on the market during their shelf life (Regulation (EC) No 2073/2005). This regulation is also applicable to unpasteurised melon and watermelon juices placed on the market during their shelf life. A Food Safety Criterion for Salmonella in whole melons and watermelons could be considered as a tool to communicate to producers and processors that Salmonella should not be present in the product. Since the occurrence of Salmonella is likely to be low, testing of whole melons or watermelons for this bacterium could be limited to instances where other factors indicate breaches in GAP, GHP, GMP or HACCP programmes.
Risk posed by Salmonella, Yersinia, Shigella and Norovirus in bulb and stem vegetables, and carrots (2014) (EFSA BIOHAZ Panel, 2014e)	To recommend, if considered relevant, microbiological criteria throughout the production chain	Assessment of impact on public health was performed	Based on epidemiological evidence (outbreak data)	Considering the limited evidence for both the occurrence and public health risks from contamination of Salmonella, Shigella, Yersinia and Norovirus in the primary production and minimal processing of bulb and stem vegetables and carrots, no conclusions can be made on the impact of the establishment of microbiological Hygiene Criteria, Process Hygiene Criteria or Food Safety Criteria on public health. There is a lack of data on the occurrence and levels of E. coli in bulb and stem vegetables as well as carrots. Thus, the effectiveness of E. coli criteria to verify compliance to Good Agricultural Practices (GAP), Good Hygiene Practices (GHP), Good Manufacturing Practices (GMP) and food safety management systems (including HACCP) in the production and minimal processing of bulb and stem vegetables as well as carrots cannot be assessed.
Risks for public health related to the presence of Bacillus cereus and other Bacillus spp. including B. thuringiensis in foodstuffs (2016) (EFSA BIOHAZ Panel, 2016)	Indicate, if possible, the maximum levels of Bacillus, and specifically of B. thuringiensis, in food that could be regarded as safe for human consumption.	Assessment of impact on public health was performed	Based on epidemiological evidence (outbreak data)	Most cases of food‐borne outbreaks caused by the B. cereus group have been associated with concentrations above 105 CFU/g. However, cases of both emetic and diarrhoeal illness have been reported involving between 103 and 105 CFU/g of B. cereus. Recently, in some food‐borne outbreaks associated with emetic B. cereus, the level of contamination of food ranged from less than 102 CFU/g to 6 × 107 CFU/g. The levels of B. cereus group posing a health risk to consumers are highly strain‐dependent due to the highly diverse pathogenic potential. The possibility of multiplication in foods after storage and/or handling must be taken into account when defining safe levels for human consumption, as well as the composition of the food, which can affect toxin production. All these factors can be responsible for the large variation in the estimated infectious dose, which makes a valid dose–response relationship hard to establish. Taking the enterotoxigenic potential into account, as well as the fact that B. thuringiensis cannot be distinguished from B. cereus at the chromosomal level, the levels of enterotoxigenic B. cereus that can be considered as a risk for consumers are also likely to be valid for B. thuringiensis.

CFU: colony‐Forming Unit(s); FSC: Food Safety Criterion(a); GAP: Good Agricultural Practices; GHP: Good Hygienic Practices; GMP: Good Manufacturing Practices; HACCP: Hazard Analysis and Critical Control Points; HAV: Hepatitis A virus; NoV: Norovirus; PHC: Process Hygiene Criterion(a); RTE: ready‐to‐eat; RT‐PCR: reverse transcription polymerase chain reaction; SCVPH: Scientific Committee on Veterinary Measures relating to Public Health; TOR: Terms of reference.