Cryptosporidium oocysts in Bent mussels (Ischadium recurvum) in the Chesapeake Bay

Filter-feeding molluscan shellfish can concentrate environmentally derived waterborne pathogens of humans, which can be utilized in the sanitary asses sment of water quality. In the present study, oocysts of Cryptosporidium we re detected in Bent mussels (Ischadium recurvum) at two Chesapeake Bay site s from which C. parvum-contaminated oysters had previously been collected. Spiking of Cryptosporidium-free blue mussel (Mytilus edulis) tissue with C. parvum oocysts showed a 51.1% recovery rate of oocysts, giving an oocyst d etection limit of 19 oocysts/0.7 mi of mussel tissue homogenate. The result s indicate that Bent mussels, which are common throughout the Chesapeake Ba y region, may prove to be useful as biological indicators of water contamin ation with Cryptosporidium oocysts.