Occurrence of Giardia and Cryptosporidium spp. in surface water supplies.
Reads0
Chats0
TLDR
The occurrence of high levels of Giardia cysts in raw water samples may require water utilities to apply treatment beyond that outlined in the Surface Water Treatment Rule of the U.S. Environmental Protection Agency.Abstract:Â
Giardia and Cryptosporidium levels were determined by using a combined immunofluorescence test for source waters of 66 surface water treatment plants in 14 states and 1 Canadian province. The results showed that cysts and oocysts were widely dispersed in the aquatic environment. Giardia spp. were detected in 81% of the raw water samples. Cryptosporidium spp. were found in 87% of the raw water locations. Overall, Giardia or Cryptosporidium spp. were detected in 97% of the raw water samples. Higher cyst and oocyst densities were associated with source waters receiving industrial or sewage effluents. Significant correlations were found between Giardia and Cryptosporidium densities and raw water quality parameters such as turbidity and total and fecal coliform levels. Statistical modeling suggests that cyst and oocyst densities could be predicted on the basis of watershed and water quality characteristics. The occurrence of high levels of Giardia cysts in raw water samples may require water utilities to apply treatment beyond that outlined in the Surface Water Treatment Rule of the U.S. Environmental Protection Agency.read more
Citations
More filters
Journal ArticleDOI
A massive outbreak in Milwaukee of cryptosporidium infection transmitted through the public water supply
Mac Kenzie Wr,N J Hoxie,Proctor Me,Gradus Ms,K A Blair,Peterson De,Kazmierczak Jj,David G. Addiss,Fox Kr,Joan B. Rose +9 more
TL;DR: This massive outbreak of watery diarrhea among the residents of Milwaukee was caused by cryptosporidium oocysts that passed through the filtration system of one of the city's water-treatment plants, and water-quality standards and the testing of patients for cryptOSporidium were not adequate to detect this outbreak.
Journal ArticleDOI
Cryptosporidium spp. and cryptosporidiosis.
Ronald Fayer,B. L. P. Ungar +1 more
TL;DR: This chapter provides an up to date review of the biology, biochemistry and host parasite relationships of Cryptosporidium.
Journal ArticleDOI
Organic polyelectrolytes in water treatment.
Brian Bolto,John Gregory +1 more
TL;DR: There is a focus on polymers for primary coagulation, their use as coagulant aids, in the recycling of filter backwash waters, and in sludge thickening.
Journal ArticleDOI
Waterborne transmission of protozoan parasites: Review of worldwide outbreaks - An update 2011-2016.
TL;DR: This review provides a comprehensive update of worldwide waterborne parasitic protozoan outbreaks that occurred with reports published since previous reviews largely between January 2011 and December 2016, and finds developing countries that are probably most affected by such waterborne disease outbreaks still lack reliable surveillance systems.
Journal ArticleDOI
Epidemiology of Cryptosporidium: transmission, detection and identification.
TL;DR: This paper reviews the valid species of Cryptosporidium, their hosts and morphometrics; the reported hosts for the human pathogen, C. parvum; the mechanisms of transmission; the drinking water, recreational water, and food-borne outbreaks resulting from infection with C.parvum%; and the microscopic, immunological, and molecular methods used to detect and identify species and genotypes.
References
More filters
Journal ArticleDOI
Large Community Outbreak of Cryptosporidiosis Due to Contamination of a Filtered Public Water Supply
Edward B. Hayes,Thomas Matte,Thomas R. O'Brien,Thomas W. McKinley,Gary S. Logsdon,Joan B. Rose,Beth L. P. Ungar,David M. Word,Margaret A. Wilson,Earl G. Long,Eugene S. Hurwitz,Dennis D. Juranek +11 more
TL;DR: Current standards for the treatment of public water supplies may not prevent the contamination of drinking water by Cryptosporidium, with consequent outbreaks of cryptosporidiosis, it is concluded.
Journal ArticleDOI
A Waterborne Outbreak of Cryptosporidiosis in Normal Hosts
Richard G. D'antonio,Richard E. Winn,Jeffery P. Taylor,Tracy L. Gustafson,William L. Current,Mamie M. Rhodes,G. William Gary,Robert A. Zajac +7 more
TL;DR: In July 1984, an outbreak of gastroenteritis occurred in a suburban community in Texas and Cryptosporidium was identified as the etiologic agent.
Journal ArticleDOI
Identification of Cryptosporidium oocysts in river water
Jerry E. Ongerth,Henry H Stibbs +1 more
TL;DR: The finding of Cryptosporidium oocysts in all samples examined from six western rivers is noteworthy in light of recent reports indicating that Cryptospora sp.
Journal ArticleDOI
Occurrence and Significance of Cryptosporidium in Water
TL;DR: Of 107 surface water samples collected in six western states, 77 were positive fo the presence of Cryptosporidium oocysts, and a high count as found in raw sewage, whereas low counts were f und in waters without waste discharg s.
Journal ArticleDOI
An outbreak of waterborne cryptosporidiosis caused by post- treatment contamination
Huw V. Smith,W. J. Patterson,R. Hardie,L. A. Greene,C. Benton,W. Tulloch,R. A. Gilmour,R. W. A. Girdwood,J. C. M. Sharp,G. I. Forbes +9 more
TL;DR: An irregular seepage of oocyst-containing water, which increased during heavy rains, was the cause of the break-pressure tank contamination, rather than a failure of the water-treatment processes.