Category Archives: Cryptosporidium

Cryptosporidium in Swiss drinking water….

Füchslin H, Egli T, Kötzsch S. Cryptosporidium spp. in drinking water. Swiss Med Wkly. 2012 Oct 4;142:0. doi: 10.4414/smw.2012.13683.

Abstract: In most rural areas and small communities in Switzerland the drinking water is supplied to the consumers after a minimum or even no treatment at all. However, it is just in these areas where drinking water from sources of agricultural activities can be contaminated by liquid manure and faeces of pasturing animals. The Swiss drinking water regulations are limited to the monitoring of E. coli, Enterococcus spp. and total plate counts only. Hence, resistant pathogens, as for example Cryptosporidium spp., remain unnoticed. During a drinking water survey, which lasted from June 2003 to December 2004, water samples were collected from 3 selected rural sites in Switzerland. The drinking water was investigated for Cryptosporidium spp., E. coli, Enterococcus spp., Clostridium perfringens and other parameters. In all samples oocysts of Cryptosporidium spp. were detected at elevated concentrations of up to 0.18 oocysts/l. Between 28% and 75% of the oocysts were found to be vital by the excystation method. Sampled oocysts collected from the three sites were subjected to genotyping and in one case the isolate was found to belong to the genotype of C. parvum. No evidence for increased incidents of diarrhoea in the past years was noted by local authorities.

Click here for full paper (fee).


Minnesota Cryptosporidium outbreak caused by water park exposure

Minnesota health officials conclude that an outbreak of Cryptosporidium, a protozoan parasite, was linked to a Duluth water park….click here….

Bajer et al 2012: Effectiveness of water treatment for the removal of Cryptosporidium and Giardia spp.

Bajer, A., B. Toczylowska, M. Bednarska, and E. Sinski. Effectiveness of water treatment for the removal of Cryptosporidium and Giardia spp. Epidemiol Infect. 2012 Jan 4:1-9.

SUMMARY: Cryptosporidium and Giardia are intestinal parasites of humans and of many other species of animals. Water constitutes an important route of transmission for human infections in both developed and developing countries. In Poland, contamination of water sources with oocysts/cysts is not routinely monitored and scientific research in this field is scarce. Our aim was to compare the contamination of surface and treated water and thus the success of water treatment processes. Water samples (n=94) of between 30 l (surface water) to over 1000 l for tap water, were taken in the period of 2008-2009 using specially constructed equipment with cartridge filtration (Filta-Max; IDEXX, USA). Immunofluorescent assay, and nested polymerase chain reaction were used for the detection of parasites. Cryptosporidium oocysts were found in 85% of surface water and in 59% of raw (intake) water samples. Oocysts were also detected in treated water (16%) but were absent in samples of swimming pool water. The highest mean number of Cryptosporidium oocysts [geometric mean (GM)=61/10 l] was found in samples of rinsing water. Giardia cysts were observed in 61% of surface water samples, in 6% of raw water and in 19% of treated water, with the highest number of cysts noted in rinsing water samples (GM=70 cysts/10 l). Our study highlights the frequent occurrence of parasites in surface waters in Poland and the effectiveness of water treatment for the removal of parasites from drinking water.


Portland (OR), Parasites, and Politics

Portland’s Bull Run watershed is a beautiful place (click here for prior post)…..A city utility worker gave me and another engineer a tour of it in 1987 (yes, that long ago)….I recall as we drove up the valley stopping at a clearing, the utility worker pointing to an area saying, this is where we would build a filtration plant if necessary.  Of course, the 1986 Safe Drinking Water Act amendments were just passed the prior year, and EPA was just beginning to work on the criteria to determine when filtration would be required (or avoided, as it turned out).  I met an EPA employee with a funny name (Stig Regli), who has since spent most of his career at EPA working on filtration and disinfection regulations.

To make a longer story short, the EPA decision to allow unfiltered water systems (like Portland) to not install filtration has always been a mixture of science and politics.  Back in the late 1980s, it was more about defining the science. Now, 15 years later….the science is pretty well-defined….and a decision to let a city avoid filtration is mostly (if not all) politics.  Democrat governor, democrat mayor, democrat local politicians running for election…. Democrat EPA administrator, President, etc….why cause economic distress  and upset voters….

Cryptosporidium has been detected once again in the Bull Run watershed….and the same arguments to avoid filtration are being made now that have been made for 15 years….same for Portland’s uncovered water storage reservoirs….the more things change the more things (in Portland) stay the same….click here….

Portland, Oregon seeks variance for Bull Run Watershed

The State of Oregon intends to issue a grant to the City of Portland from the requirement to treat the Bull Run Watershed source for Cryptosporidium.

A public hearing is scheduled for December 14 from 5 to 7 pm in the Portland State Office Building, 800 N.E. Oregon Street, Room 1B.

Written comments may be submitted until 5 pm January 3, 2012.  Submit written comments to:

Oregon Health Authority-Public Health Division, Office of Environmental Public Health, Drinking Water Program, 800 N.E. Oregon St., Suite 640, Portland, OR 97232.

Click here for a copy of the Notice of Intent and information on submitting written comments.

After reviewing the comments a final order will be issued effective Jan. 31, 2012.

Cryptosporidum health effects can linger for years….

Six years later, a woman in North Wales is still impacted by having ingested tap water contaminated with Cryptosporidium….click here for more…

Xiao et al 2011: Occurrences and genotypes of Cryptosporidium oocysts in river network of southern-eastern China

S. Xiao, W. An, Z. Chen, D. Zhang, J. Yu, and M. Yang.  Occurrences and genotypes of Cryptosporidium oocysts in river network of southern-eastern China. Parasitology Research, 2011 Oct 19.

State Key Laboratory of Environmental Aquatic Chemistry, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China,

Absract: Transportation of Cryptosporidium oocysts in river type source water is of great concern in an area where extensive human activities exist. In this study, a total of 47 samples were collected from Tongxiang, China, where drinking source water was taken from a complicated river network system, by three sampling campaigns over a rainy season in 2009, to reveal the presence, genotypes, and likely source of Cryptosporidium oocysts in river water. Immunofluorescence microscopy analyses show that 37 (78.7%) were Cryptosporidium positive, with a mean concentration of 0.51 oocysts per liter. These results suggest that the protozoa were commonly distributed in the river network type source water of Tongxiang with a relatively low concentration level. PCR analysis was used to determine the species/genotypes of Cryptosporidium, which revealed the presence of the animal related species/genotypes including Cryptosporidium suis, Cryptosporidium fragile, and the avian III, pig II, cervine genotypes. Three of them were also detected in wastewater samples taken from neighboring animal farms, showing that farm animals rather than human might be the major pollution sources. This is the first report on simultaneous detection and genotyping of Cryptosporidium oocysts from surface water in China.

Click here for the full paper (fee).