| cryptosporidium parvum in oysters from commercial harvesting sites in the chesapeake bay. | oocysts of cryptosporidium parvum, a zoonotic waterborne pathogen, can be removed by bivalve molluscs from contaminated water and retained on gills and in hemolymph. we identified oocysts of c. parvum in oysters from seven sites in the chesapeake bay area. these findings document the presence of c. parvum infectious for humans in oysters intended for human consumption. | 1999 | 10511528 |
| susceptibility of the chesapeake bay to environmental contamination with cryptosporidium parvum. | | 2000 | 10662525 |
| active, multisite, laboratory-based surveillance for cryptosporidium parvum. | cryptosporidium parvum leaped to the attention of the united states following the 1993 outbreak in milwaukee, wisconsin, which sickened 400,000 people. other outbreaks in the united states have been associated with drinking and recreational water, consumption of contaminated foods, contact with animals, and childcare attendance. despite its public health importance, the number of people who become infected each year is not known. in 1997, active surveillance for c. parvum was added to the foodbo ... | 2000 | 11037779 |
| recovery, bioaccumulation, and inactivation of human waterborne pathogens by the chesapeake bay nonnative oyster, crassostrea ariakensis. | the introduction of nonnative oysters (i.e., crassostrea ariakensis) into the chesapeake bay has been proposed as necessary for the restoration of the oyster industry; however, nothing is known about the public health risks related to contamination of these oysters with human pathogens. commercial market-size c. ariakensis triploids were maintained in large marine tanks with water of low (8-ppt), medium (12-ppt), and high (20-ppt) salinities spiked with 1.0 x 10(5) transmissive stages of the fol ... | 2006 | 16672482 |
| prevalence of cryptosporidium species and genotypes in mature dairy cattle on farms in eastern united states compared with younger cattle from the same locations. | feces collected from 541 milking cows on two dairy farms each in vermont, new york, pennsylvania, maryland, virginia, north carolina, and florida were examined for the presence of cryptosporidium oocysts. oocysts were concentrated from 15 g of feces from each cow and dna was extracted. a two-step nested pcr protocol was used to amplify an 830 base pair fragment of the ssurrna gene. pcr-positive products were purified and sequenced. pcr-positive findings were obtained from cows in all seven state ... | 2007 | 17287086 |
| prevalence and molecular characterization of cryptosporidium and giardia species and genotypes in sheep in maryland. | in the united kingdom and australia sheep have been implicated as sources of cryptosporidium and giardia that infect humans, but no such studies have been conducted in north america. therefore, a study was undertaken to investigate the prevalence of these parasites in sheep on a farm in maryland. feces were collected from 32 pregnant ewes 1, 2, and 3 days after parturition and from each of their lambs 7, 14, and 21 days after birth. the presence of cryptosporidium oocysts and giardia cysts was d ... | 2007 | 17335979 |