Bivalve mollusks are an important food resource worldwide, including Italy, and Sardinia Region is among the leading producers of Mytilus spp. EU legislation on shellfish products only regards bacterial pathogens, but emerging protozoan parasites are widespread and create health problems, mostly in young and immune-compromised persons. The aim of this study was to investigate the prevalence and seasonality of Giardia duodenalis, Cryptosporidium spp. and Toxoplasma gondii in two mussel species both farmed along the Sardinian coast, and available on the market. From September 2013 to July 2014, 1620 shellfish specimens i.e. 1440 Mytilus galloprovincialis and 180 Mytilus edulis, were collected from 17 farms and 118 retail outlets in 8 areas of Sardinia and then pooled. Digestive glands and gills were removed from all specimens and a total of 135 pool samples were tested. After DNA extraction, the samples were tested by Real Time-PCR assay to detect G. duodenalis (ssRNA), Cryptosporidium spp. (COWP) and T. gondii (B1) and sequenced. Sixty-two of the 135 (45.9%, 95% CI=37.5-54.3%) mussel pools tested positive for one or more investigated pathogens. Both Mytilus spp. and samples from all investigated areas harboured pathogens. Mussels were statistically more contaminated by Cryptosporidium parvum followed by G. duodenalis Assemblage A and T. gondii, and M. galloprovincialis was more contaminated than M. edulis (p<0.01). Contamination was more likely in farmed mussels (p<0.05) and those collected in spring (p<0.01). No statistically significant differences were registered between the anatomical sites. This study confirms that mussels farmed and marketed in Italy are contaminated by zoonotic protozoans. This is the first report of T. gondii in both Mediterranean mussel M. galloprovincialis and Blue mussel M. edulis. These results indicate a considerable threat to human health, particularly if mussels are eaten raw. Thus, modification/revision of the present EU law can no longer be delayed.
Zoonotic protozoans from farmed and marketed Mytilus spp in Sardinia (Italy)
Marangi, Marianna;CARADONNA, TIZIANA;NORMANNO, GIOVANNI GIUSEPPE;GIANGASPERO, ANNUNZIATA
2016-01-01
Abstract
Bivalve mollusks are an important food resource worldwide, including Italy, and Sardinia Region is among the leading producers of Mytilus spp. EU legislation on shellfish products only regards bacterial pathogens, but emerging protozoan parasites are widespread and create health problems, mostly in young and immune-compromised persons. The aim of this study was to investigate the prevalence and seasonality of Giardia duodenalis, Cryptosporidium spp. and Toxoplasma gondii in two mussel species both farmed along the Sardinian coast, and available on the market. From September 2013 to July 2014, 1620 shellfish specimens i.e. 1440 Mytilus galloprovincialis and 180 Mytilus edulis, were collected from 17 farms and 118 retail outlets in 8 areas of Sardinia and then pooled. Digestive glands and gills were removed from all specimens and a total of 135 pool samples were tested. After DNA extraction, the samples were tested by Real Time-PCR assay to detect G. duodenalis (ssRNA), Cryptosporidium spp. (COWP) and T. gondii (B1) and sequenced. Sixty-two of the 135 (45.9%, 95% CI=37.5-54.3%) mussel pools tested positive for one or more investigated pathogens. Both Mytilus spp. and samples from all investigated areas harboured pathogens. Mussels were statistically more contaminated by Cryptosporidium parvum followed by G. duodenalis Assemblage A and T. gondii, and M. galloprovincialis was more contaminated than M. edulis (p<0.01). Contamination was more likely in farmed mussels (p<0.05) and those collected in spring (p<0.01). No statistically significant differences were registered between the anatomical sites. This study confirms that mussels farmed and marketed in Italy are contaminated by zoonotic protozoans. This is the first report of T. gondii in both Mediterranean mussel M. galloprovincialis and Blue mussel M. edulis. These results indicate a considerable threat to human health, particularly if mussels are eaten raw. Thus, modification/revision of the present EU law can no longer be delayed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
