Evaluation of short purification cycles in naturally contaminated Mediterranean mussels (Mytilus galloprovincialis) harvested in Sardinia (Italy)

Enumeration of <em>Escherichia coli</em> and determination of <em>Salmonella</em> spp. and verotoxigenic <em>Escherichia coli</em> in shellfish (<em>Mytilus galloprovincialis</em> and <em>Ruditapes decussatus</em>) harvested in Sardinia, Italy

“…The purification treatment allowed a slight reduction in E. coli loads (p<0.01) only in the latter species. On the contrary, in Sferlazzo et al ( 2018 ), purification allowed a progressive and significant reduction in E. coli loads (p<0.01) in 10 batches of M. galloprovincialis . However, the results of E. coli load were consistently in agreement with the legislation limits for class A harvesting areas (EU 2285/2015).…”

“…To evaluate the effects of purification on the safety of shellfish, samples (n. 20) from selected batches (n. 5) were collected after purification. The purification centers annexed to both production areas, applied short ‘‘recirculating’’ purification protocols (8h) previously described in Sferlazzo et al ( 2018 ). The shellfish harvesting areas ( Figure 1 ) were on the central-western coast (production area A) and on the North- Eastern coast of Sardinia (production area O).…”

“…Several authors reported a prevalence of Salmonella spp. in shellfish samples collected in Italy, ranging from 0 to 3.1% (Bazzoni et al , 2019 ; Carraro et al , 2015 ; Marceddu et al , 2017 ; Prato et al , 2013 ; Rubini et al , 2018 ; Sferlazzo et al ., 2018 ;). Although Salmonella spp.…”

“…It is well known that shellfish contamination occurs because bivalve molluscs are filter-feeding animals that selectively filter and accumulate small particles of phytoplankton, zooplankton, viruses, bacteria and inorganic matter from the environment (Carella et al , 2010 ; Leoni et al , 2017 ). This highlights the role of shellfish as vehicle for several hazards that could result in products that are unsuitable to guarantee the safety of consumers, particularly if live bivalve molluscs are consumed raw or lightly cooked (Rubini et al , 2018 ; Sferlazzo et al , 2018 ). Bivalve molluscs transmitted illness can be either due to indigenous bacteria as Vibrio species (Smaldone et al , 2014 ; Leoni et al , 2016 ) or from non-indigenous bacteria, usually enteric bacteria, derived from fecal contamination (mostly Salmonella spp., E. coli VTEC , Shigella spp.)…”

“…Shellfish harvested in these areas can consequently concentrate the pathogen and thereby pose a risk to the health of consumers (Marceddu et al ., 2017 ). Sardinia is one of the nationally relevant Italian shellfish production areas: the annual production accounts for 83% of the regional aquaculture, and it almost exclusively rests on M. galloprovincialis (Meloni et al , 2015 ; Sferlazzo et al , 2018 ). Specific literature in the Sardinian shellfish harvesting areas is limited.…”