Investigation into Cryptosporidium and Giardia in bivalve mollusks farmed in Sardinia region and destined for human consumption

Cryptosporidium and Giardia are protozoan parasites transmitted by fecal-oral ingestion of (oo)cysts, and are responsible for enteritis in several animal species and humans worldwide. These (oo)cysts can survive for over a year in aquatic environments and can accumulate in bivalve mollusks, which filter large volumes of water. The aim of this study is to evaluate the natural occurrence of Cryptosporidium and Giardia contamination in different specimens of edible bivalves mollusks from farming sites of the western and north-eastern coasts of Sardinia. From April 2011 to February 2012, 1095 specimens of Mytilus galloprovincialis and 240 of Crassostrea gigas were sampled from Olbia and Oristano gulf and San Teodoro pond. Hepatopancreas and gills, including the labial palp, were examined for oocysts and cysts after pooling and homogenisation using different techniques: i) staining for light and fluorescence microscopy; ii) direct immunofluorescence (IF) Merifluor® test Cryptosporidium/ Giardia (Meridian Bioscience Inc., Cincinnati, OH, USA); and iii) molecular procedures. However, in the context under study, all mollusks examined with the three main diagnostic techniques were negative for both parasites pointing out the hypothetically low zoonotic risk related to Cryptosporidium and Giardia in bivalves, especially Mytilus galloprovincialis and Crassostrea gigas

Functionalized aliphatic polyketones with germicide activity

The COVID-19 pandemic has further confirmed to the community that direct contact with contaminated surfaces and objects represents an important source of pathogen spreading among humans. Therefore, it is of paramount importance to design effective germicidal paints to ensure a rapid and potent disinfectant action of surfaces. In this work, we design novel germicide polymeric coatings by inserting quaternary ammonium and sugar groups on the macromolecular backbone, thus respectively endowing the polymer with germicide features and hydrophilicity to interact with the surfaces. An aliphatic polyketone was selected as a starting polymer matrix that was functionalized with primary amine derivatives via the Paal–Knorr reaction. The resulting polymers were deposited on cellulose filter papers and checkboard charts with excellent coating yield and substrate coverage as determined by scanning electron microscopy for cellulose. Remarkably, the substrates coated by the functional polymers bearing quaternary ammonium compounds showed excellent bactericide properties with antibacterial rate of 99% and logarithmic reduction of >3. Notably, the polymers with higher hydrophobicity showed better retention on the substrate after being treated with water at neutral pH

Bacterial and viral investigations combined with determination of phytoplankton and algal biotoxins in mussels and water from a Mediterranean coastal lagoon (Sardinia, Italy).

Calich Lagoon is a Mediterranean coastal lagoon located along the northwestern coast of Sardinia (Italy). The connection to marine and fresh water determines the high productivity of this coastal lagoon. Despite its great potential and the presence of natural beds of bivalve mollusks (Mytilus galloprovincialis), the lagoon has not yet been classified for shellfish production. In this study, through a multidisciplinary approach, the presence of several bacterial pathogens (Escherichia coli, Salmonella spp., and Vibrio spp.) and viral pathogens (hepatitis A virus and norovirus genogroups I and II) was evaluated from March 2017 to February 2018. In addition, phytoplankton composition in lagoon waters and associated algal biotoxins (paralytic and diarrhetic shellfish poisoning) in mussels were also monitored. The aim of this study was to provide useful data to improve knowledge about their seasonal presence and to assess the potential risk for public health, as well as to provide input for future conservation and management strategies. In mussels, Salmonella spp. were found in spring, along with E. coli, but Salmonella spp. were not found in autumn or winter, even though E. coli was detected in these seasons. Vibrio parahaemolyticus was found in autumn and winter, but not in spring. Norovirus genogroups I and II were found in winter samples. None of the bacteria were found in summer. Algal biotoxins have never been detected in mussel samples. Among potentially harmful phytoplankton, only Pseudo-nitzschia spp. were present, mainly in summer. The results showed that a possible bacterial and viral contamination, together with the presence of potentially toxic microalgae, is a real problem. Therefore, the development of natural resource management strategies is necessary to ensure the good quality of waters and guarantee the protection of consumers

Paralytic shellfish poison algal biotoxins: Sardinia report 2002-2011 and non-compliance management

Several microalgae of the genus Alexandrium (Alexandrium minutum and Alexandrium catenelle) can produce an algal biotoxin, the paralytic shellfish poison (PSP) that can be accumulated in the shellfish edible tissues making them hazardous to the consumer’s health. In this paper we report i) the results of PSP toxins survey carried out by mouse bioassays (mouse test AOAC 958.08) on 7457 samples of bivalve molluscs farmed in Sardinia and in other European countries and marketed in Sardinia region from 2002 to 2011, and ii) the management of positive cases. Based on our experience it is very important to strictly apply the planned activities in order to prevent any risk and to protect the consumer’s and producer’s health

New evidence of pectenotoxins in farmed bivalve molluscs from Sardinia (Italy)

Several planktonic dinoflagellates can produce lipophilic phycotoxins that represent a significant threat to public health as well as to shellfish and fish farming. Poisoning related to some of these toxins is categorised as diarrhetic shellfish poisoning. We analysed 975 shellfish samples from Tortolì in the central-eastern region of Sardinia (Italy) from January 2016 to March 2020, to investigate the prevalence of different lipophilic marine biotoxins in mollusc bivalves. The results highlighted the predominant presence of toxins belonging to the okadaic acid group in all samples with toxin concentrations exceeding legal limits, and revealed the new occurrence of pectenotoxins in oysters and clams with a winter seasonality in recent years. The origin of shellfish toxicity was associated with the same Dinophysis species, mainly D. acuminata. Based on both these results and other precedents, monitoring and recording systems are strongly recommended

Identification and quantification of potential microplastics in shellfish harvested in Sardinia (Italy) by using transillumination stereomicroscopy

Plastics are non-biodegradable polymers made up of different groups of petrochemical materials. Several biotic and abiotic factors can change the density of plastic fragmenting it and originating microplastics (MPs). MPs have been defined as small pieces of plastic less than 5 mm in size. Due to their small size, they are an emerging concern in the marine environment since they can be ingested by aquatic organisms, especially filter-feeding organisms, such as bivalve mollusks. Impacts of MPs exposure have been shown at various levels of biological organization, from cellular to tissue to individual and population levels. For example, oxidative stress and inflammation have been observed in copepods and mussels, obstruction and physical damage of the digestive tract were found in fish and swimming behavior alterations, disruption of foraging and feeding behavior and overall reduced fitness and survival were observed in fish and oysters. In addition, MPs can act as a vector for the transfer of chemicals to marine biota. The aim of the present study was the identification and quantification of potential MPs in shellfish harvested in Sardinia (Italy) by using transillumination stereomicroscopy. Bivalves were collected from 4 of the main production areas located along the Sardinian coast and selected according to the principles of the risk assessment. The results of the present study demonstrated the presence of potential MPs in 70% of the analyzed samples: the presence of MPs in bivalve mollusks may pose a threat to food safety, and there is an urgent need to evaluate the potential risks of MPs to human health

COVID-19 Severity in Multiple Sclerosis: Putting Data Into Context

Background and objectives: It is unclear how multiple sclerosis (MS) affects the severity of COVID-19. The aim of this study is to compare COVID-19-related outcomes collected in an Italian cohort of patients with MS with the outcomes expected in the age- and sex-matched Italian population. Methods: Hospitalization, intensive care unit (ICU) admission, and death after COVID-19 diagnosis of 1,362 patients with MS were compared with the age- and sex-matched Italian population in a retrospective observational case-cohort study with population-based control. The observed vs the expected events were compared in the whole MS cohort and in different subgroups (higher risk: Expanded Disability Status Scale [EDSS] score > 3 or at least 1 comorbidity, lower risk: EDSS score ≤ 3 and no comorbidities) by the χ2 test, and the risk excess was quantified by risk ratios (RRs). Results: The risk of severe events was about twice the risk in the age- and sex-matched Italian population: RR = 2.12 for hospitalization (p < 0.001), RR = 2.19 for ICU admission (p < 0.001), and RR = 2.43 for death (p < 0.001). The excess of risk was confined to the higher-risk group (n = 553). In lower-risk patients (n = 809), the rate of events was close to that of the Italian age- and sex-matched population (RR = 1.12 for hospitalization, RR = 1.52 for ICU admission, and RR = 1.19 for death). In the lower-risk group, an increased hospitalization risk was detected in patients on anti-CD20 (RR = 3.03, p = 0.005), whereas a decrease was detected in patients on interferon (0 observed vs 4 expected events, p = 0.04). Discussion: Overall, the MS cohort had a risk of severe events that is twice the risk than the age- and sex-matched Italian population. This excess of risk is mainly explained by the EDSS score and comorbidities, whereas a residual increase of hospitalization risk was observed in patients on anti-CD20 therapies and a decrease in people on interferon

DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR = 2.05, 95%CI = 1.39–3.02, p < 0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR = 0.42, 95%CI = 0.18–0.99, p = 0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon

Efficacia della depurazione sulla sicurezza di mitili (<i>Mytilus galloprovincialis</i>) allevati nel golfo di Olbia = Efficacy of depuration on safety of Mediterranean mussels (<i>Mytilus galloprovincialis</i>) reared in the Olbia Gulf

The aim of the present study was to investigate the effect of depuration on the safety of Mediterranean mussels harvested in the Olbia gulf and to evaluate the efficacy of E.coli and Salmonella spp. as indicators of the presence of naturally occurring Vibrios and other pathogens (viruses causing hepatitis, L.monocytogenes and S.aureus). Samples of mussels belonging to 5 batches of products, from 2 Depuration Centers, were collected before depuration (T0), after 4h (T4) and at the end of depuration (T8). Results showed an overall efficacy of the depuration in respect to E.coli moderate counts. A depuration for ~8 hours led to a rapid decline in the concentration, complying to the Food Safety Criteria of the Reg. (EC) 2073/2005. The decline in numbers of E. coli, does not correlate with the presence of naturally occurring Vibrios, which decline at an even slower rate. The adoption of shorter treatments times for mussels with high initial counts of Vibrios could lead to a reduction unfitted to guarantee the safety of consumers