title: Mussels (Perna perna) as bioindicator of environmental contamination by Cryptosporidium species with zoonotic potential.
abstract: Sources of contamination such as animal feces runoff, organic fertilizer application, and the release of partially treated or untreated sewage can lead to the contamination of aquatic environments by Cryptosporidium spp. The quality of mussels as food is closely related to the sanitary conditions of the marine environment where these bivalves are found. Marine mollusks are filter feeders that are able to retain Cryptosporidium oocysts in their tissue, thus functioning as bioindicators. A total of 72 pooled mussel samples of the species Perna perna were collected at two sites (A and B) in the municipality of Mangaratiba, Rio de Janeiro State, Brazil. Sampling involved removal of 30 mussels, from each collection site every month for one year. The 30 mussels from each sampling were then allocated into three groups of 10. Two Cryptosporidium spp. genes (18S and GP60) were targeted for DNA amplification from the samples obtained. After purification, all of the products obtained were sequenced and phylogenetic analyses were performed. Of the 72 samples analyzed using the nested-PCR for the 18S gene target, 29.2% were positive for the presence of Cryptosporidium spp. Of these samples, 52.4% were collected at site A (ie 11/21) and 47.6% at site B (ie 10/21). The 18S genes of all the samples considered positive for Cryptosporidium spp. were sequenced, and the following three species were identified: Cryptosporidium parvum, C. meleagridis, and C. andersoni. Three distinct C. parvum subtypes (IIaA19G2R2; IIaA20G2R2; IIaA20G3R2) were identified using the GP60 gene. More studies to evaluate the zoonotic potential of this species should be performed as both sampling locations contain human and/or animal fecal contaminants.
authors.affiliation: Educacional Foundation Rosemar Pimentel, University Center Geraldo Di Biase - Barra do Piraí, Brazil.
authors.forename: Geisi Ferreira
authors.initials: GF
authors.lastname: Mariné Oliveira
authors.affiliation: Federal Rural University of Rio de Janeiro, Institute of Biology, Department of Physiological Sciences, Brazil.
authors.forename: Melissa Carvalho Machado
authors.initials: MC
authors.lastname: do Couto
authors.affiliation: Federal Rural University of Rio de Janeiro - Chemistry Department, Institute of Exact Sciences, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: de Freitas Lima
authors.affiliation: Federal Rural University of Rio de Janeiro, Veterinary Institute, Department of Animal Parasitology, BR 465, Km 07, Seropédica, Rio de Janeiro 23.890-000 Brazil.
authors.forename: Teresa Cristina Bergamo
authors.initials: TC
authors.lastname: do Bomfim
keywords: 18S; Cryptosporidium; Environmental indicator; GP60; Marine bivalve