Publications

first detection of microsporidia in dairy calves in north america.	fecal specimens were obtained from a total of 413 dairy calves from farms in vermont, new york, pennsylvania, maryland, virginia, north carolina, and florida. after removal of fecal debris by sieving and density gradient centrifugation, specimens were examined by fluorescence microscopy, polymerase chain reaction (pcr), and dna sequencing analysis for the presence of microsporidia. microscopic examination revealed no spores. pcr using generic primers for microsporidia revealed 70 positive calves ...	2003	12739131
molecular characterization of enterocytozoon bieneusi in cattle indicates that only some isolates have zoonotic potential.	in this study, 338 fecal samples were analyzed for enterocytozoon bieneusi from cattle farms in florida, maryland, michigan, new york, north carolina, pennsylvania, virginia, and portugal. the internal transcribed spacer region (392 bp) of the rrna gene of e. bieneusi was amplified using a nested pcr protocol. thirty-two e. bieneusi-pcr positive samples were sequenced. a high degree of genetic polymorphism, represented by five distinct genotypes (beb1-beb5), was found among the e. bieneusi isola ...	2004	14727187
prevalence of enterocytozoon bieneusi in post-weaned dairy calves in the eastern united states.	fecal specimens were obtained from 3- to 8-month-old post-weaned dairy calves on farms in vermont, new york, pennsylvania, maryland, virginia, north carolina, and florida. after removal of fecal debris by sieving and density gradient centrifugation, 59 of 452 calves (13%) from 11 farms in six states were found positive for enterocytozoon bieneusi by pcr and dna sequence analysis. based on gene sequence data this genotype of e. bieneusi found in post-weaned calves was 100% identical to that found ...	2004	15170566
enterocytozoon bieneusi genotypes in dairy cattle in the eastern united states.	fecal specimens were obtained from 12-24-month-old dairy heifers on farms in vermont, new york, pennsylvania, maryland, virginia, north carolina, and florida. pcr positive specimens for enterocytozoon bieneusi were found in 131 of 571 heifers examined (23%) and on all the farms visited. the prevalence of e. bieneusi varied considerably across farms, with the lowest prevalence (4.7%) on md-2 and the highest prevalence (37.8%) on ny-2. all pcr positive specimens that amplified the its region as we ...	2005	16167161
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
quantitative evaluation of the impact of bather density on levels of human-virulent microsporidian spores in recreational water.	microsporidial gastroenteritis, a serious disease of immunocompromised people, can have a waterborne etiology. during summer months, samples of recreational bathing waters were tested weekly for human-virulent microsporidian spores and water quality parameters in association with high and low bather numbers during weekends and weekdays, respectively. enterocytozoon bieneusi spores were detected in 59% of weekend (n = 27) and 30% of weekday (n = 33) samples, and encephalitozoon intestinalis spore ...	2007	17483272
enterocytozoon bieneusi in mature dairy cattle on farms in the eastern united states.	fecal specimens were obtained from mature milking cows on farms in vermont, new york, pennsylvania, maryland, virginia, north carolina, and florida. polymerase chain reaction (pcr)-positive specimens for enterocytozoon bieneusi were found in 24 of 541 cows examined (4.4%) and on 12 of 14 farms. the prevalence of e. bieneusi varied considerably from farm to farm, with the lowest prevalence (2.3%) on fl-2 and the highest prevalence (12.5%) on vt-2. none of the cows exhibited signs of diarrhea. all ...	2007	17899197
a longitudinal study of enterocytozoon bieneusi in dairy cattle.	feces from each of 30 holstein cattle on a maryland dairy farm were examined at weekly, bimonthly, and then monthly intervals from 1 week to 24 months of age for the presence of enterocytozoon bieneusi. dna was extracted from spores cleaned of fecal debris, and a two-step nested pcr protocol was used to amplify a fragment of the internal transcriber spacer region of the rrna gene. all pcr-positive specimens were sequenced to determine the genotype of e. bieneusi. the overall prevalence was 24% ( ...	2009	19259701
enterocytozoon bieneusi, giardia, and cryptosporidium infecting white-tailed deer.	despite a white-tailed deer (wtd) population in the united states of approximately 32 million animals extremely little is known of the prevalence and species of the protists that infect these animals. this study was undertaken to determine the presence of potential human protist pathogens in culled wtd in central maryland. feces from fawns to adults were examined by molecular methods. the prevalence of enterocytozoon bieneusi, cryptosporidium, and giardia was determined by pcr. all pcr-positive ...	2015	25066778