Monitoring of bivalve mollusk harvesting areas: the relevance of Salmonella spp.

Submitted: 28 November 2023
Accepted: 4 March 2024
Published: 15 March 2024
Abstract Views: 1235
PDF: 13
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The microbiological monitoring of bivalve mollusk harvesting areas in the Marche region is based on the parameters of Escherichia coli and Salmonella spp. However, Regulation EU/2019/627 stated criteria based on E. coli only to determine the health status of these areas. Therefore, the reason for Salmonella spp. monitoring, as provided in the Marche region, could be aimed at reducing the risk of placing on the market contaminated bivalve mollusks. This study, using the results of microbiological monitoring carried out in the Marche region from 2015 to 2022 and the methods based on Bayes’ theorem and Poisson’s distribution, evaluated the effectiveness and efficiency of Salmonella spp. monitoring in reducing the risk to the consumer. The results show that i) the use of a single sample unit significantly reduced the possibility of detecting non-compliance with the microbiological safety criterion; ii) the time taken to report positive results (average of approximately 10 days) did not allow the timely implementation of control measures; iii) the prevalence of positive outcomes was quite sporadic: a random trend of positivity is recognizable on a geographical and monthly basis for mussels and a geographical basis for striped clams; iv) considering the predictive value of E. coli against Salmonella spp., the specificity is very high and the negative predictive value versus Salmonella spp. would be >80%. In conclusion, the study shows that the monitoring of Salmonella spp. has a limited effect on reducing the risk to the consumer; however, in the cost/benefit assessment, other aspects not covered by this study should be considered.

Bazzoni AM, Mudadu AG, Esposito G, Urru R, Ortu S, Mara L, Uda MT, Arras I, Lorenzoni G, Sanna G, Bazzardi R, Marongiu E, Virgilio S, Meloni D, 2019. Bacterial and viral investigations combined with determination of phytoplankton and algal biotoxins in mussels and water from a Mediterranean coastal lagoon (Sardinia, Italy). J Food Protect 82:1509-11.

Ciccarelli C, Semeraro AM, Leinoudi M, Di Trani V, Ciampana A, Ciccarelli E, 2023. Sample size planning and the statistical significance of official controls by sampling. Ital J Food Safety 12:11119.

Cioffi B, Ianiro G, Iaccarino D, D’Apice F, Ferraro A, Race M, Spasiano D, Esposito E, Monini M, Serra F, Cozza D, Di Nocera F, De Maio L, Amoroso MG, De Carlo E, Fusco G, 2021. A potential risk assessment tool to monitor pathogens circulation in coastal waters. Environ Res 200:111748.

European Commission, 2005. Regulation (EU) n. 2073/2005 of the European Commission of 5 December 2005 laying down implementing measures for certain products under Regulation (EC) No 853/2004 of the European Parliament and of the Council and for the organisation of official controls under Regulation (EC) No 854/2004 of the European Parliament and of the Council and Regulation (EC) No 882/2004 of the European Parliament and of the Council, derogating from Regulation (EC) No 852/2004 of the European Parliament and of the Council and amending Regulations (EC) No 853/2004 and (EC) No 854/2004. In: Official Journal, L 338/1, 22/12/2005.

European Commission, 2019. Regulation (EU) 2019/627 of the European Commission of 5 March 2019 laying down uniform practical arrangements for the performance of official controls on products of animal origin intended for human consumption in accordance with Regulation (EU) 2017/625 of the European Parliament and of the Council and amending Commission Regulation (EC) No 2074/2005 as regards official controls). In: Official Journal, L 131/51, 17/05/2019.

European Commission, 2021. Community guide to principles of good practice for the microbiological classification and monitoring of bivalve mollusc production and relaying areas with regard to implementing Regulation 2019/627. Available from:

FAO, WHO, 2021. Technical guidance for the development of the growing area aspects of bivalve mollusc sanitation programmes. Second edition. Available from:

Hood MA, Ness GE, Blake NJ, 1983. Relationship among faecal coliforms, Escherichia coli, and Salmonella spp. in shellfish. Appl Environ Microbiol 45:122-6.

ISO, 2015. Microbiology of the food chain. Horizontal method for the enumeration of beta-glucuronidase-positive Escherichia coli. Part 3: detection and most probable number technique using 5-bromo-4-chloro-3-indolyl-ß-D-glucuronide. ISO Norm 16649-3:2015. International Standardization Organization ed., Geneva, Switzerland.

ISO, 2017. Microbiology of the food chain. Horizontal method for the detection, enumeration and serotyping of Salmonella. Part 1: detection of Salmonella spp. ISO Norm 6579-1:2017. International Standardization Organization ed., Geneva, Switzerland.

Korajkic A, Wanjugi P, Brooks L, Cao Y, Harwood VJ, 2019. Persistence and decay of faecal microbiota in aquatic habitats. Microbiol Mol Biol Rev 83:e00005-19.

Martinez-Urtaza J, Liebana E, Garcia-Migura L, Perez-Piñeiro P, Saco M, 2004. Characterization of Salmonella enterica serovar Typhimurium from marine environments in coastal waters of Galicia (Spain). Appl Environ Microbiol 70:4030-4.

Martinez-Urtaza J, Saco M, de Novoa J, Perez-Piñeiro P, Peiteado J, Lozano-Leon A, Garcia-Martin O, 2004. Influence of environmental factors and human activity on the presence of Salmonella serovars in a marine environment. Appl Environ Microbiol 70:2089-97.

Rincé A, Balière C, Hervio-Heath D, Cozien J, Lozach S, Parneudeau S, Le Guyadier SF, Le Hello S, Giard J-C, Sauvageot N, Benachour A, Strubbia S, Gourmelon M, 2018. Occurrence of bacterial pathogens and human noroviruses in shellfish-harvesting areas and their catchments in France. Front Microbiol 9:2443.

Rozen Y, Belkin S, 2001. Survival of enteric bacteria in seawater. FEMS Microbiol Rev 25:513-29.

Rubini S, Galletti G, D’Incau M, Govoni G, Boschetti L, Berardelli C, Barbieri S, Merialdi G, Formaglio A, Guidi E, Bergamini M, Piva S, Serraino A, Giacometti S, 2018. Occurrence of Salmonella enterica subsp. enterica in bivalve molluscs and associations with Escherichia coli in molluscs and faecal coliforms in seawater. Food Control 84:429-35.

Setti I, Rodriguez-Castro A, Pata MP, Cadarso-Suarez C, Yacoubi B, Bensmael L, Moukrim A, Martinez-Urtaza J, 2009. Characteristics and dynamics of Salmonella contamination along the coast of Agadir, Morocco. Appl Environ Microbiol 75:7700-9.

Simental L, Martinez-Urtaza J, 2008. Climate patterns governing the presence and permanence of salmonellae in coastal areas of Bahia de Todos Santos, Mexico. Appl Environ Microbiol 74:5918-24.

Winfield MD, Groisman EA, 2003. Role of non-host environments in the lifestyles of Salmonella and Escherichia coli. Appl Environ Microbiol 69:3687-94.

Ciccarelli C, Semeraro AM, Di Trani V, D’Aurizio G, Blasi G, Leinoudi M, De Simoni C, Ciccarelli E. Monitoring of bivalve mollusk harvesting areas: the relevance of <i>Salmonella</i> spp. Ital J Food Safety [Internet]. 2024 Mar. 15 [cited 2024 May 18];13(2). Available from:


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