scholarly journals Occurrence of Cryptosporidium Oocysts and Giardia Cysts in Sewage in Norway

2006 ◽  
Vol 72 (8) ◽  
pp. 5297-5303 ◽  
Author(s):  
L. J. Robertson ◽  
L. Hermansen ◽  
B. K. Gjerde
Keyword(s):  
Sewage Treatment ◽  
Giardia Duodenalis ◽  
Infection Intensity ◽  
Treatment Processes ◽  
Cryptosporidium Oocysts ◽  
Water Courses ◽  
Minimal Treatment ◽  
Two Populations ◽  
Substantial Heterogeneity ◽  
Assemblage B

ABSTRACT Samples of sewage influent from 40 sewage treatment works (STW) throughout Norway were examined for Cryptosporidium oocysts and Giardia duodenalis cysts. Both parasites were detected frequently (80% of STW were Cryptosporidium positive; 93% of STW were Giardia positive) and at maximum concentrations of >20,000 parasites/liter. The data suggest giardiasis is more widespread, and/or occurs with greater infection intensity, than cryptosporidiosis in Norway. STW serving higher person equivalents were more likely to be positive and had higher parasite concentrations. Parasite concentrations were used to estimate the proportion of contributing populations that could be clinically infected. For Cryptosporidium, the highest estimates were up to 5 per 100,000 individuals for two populations in eastern Norway. For Giardia, the highest estimate was 40 infected per 100,000 persons (approximately five times the usual national annual average) contributing to an STW in western Norway. As this population experienced a large waterborne giardiasis outbreak 6 months after sampling, it can be speculated that regular challenge with Giardia may occur here. Most Giardia isolates in sewage influent were assemblage A, although some assemblage B isolates were detected. There was substantial heterogeneity, but most samples contained isolates similar to genotype A3. Removal efficiencies at two STW with secondary treatment processes were estimated to be approximately 50% for Cryptosporidium and >80% for Giardia. An STW with minimal treatment had negligible removal of both parasites. Many STW in Norway have minimal treatment and discharge effluent into rivers and lakes, thus, risk of contamination of water courses by Cryptosporidium and Giardia is considerable.

Detection of Cyclospora, Cryptosporidium, and Giardia in Ready-to-Eat Packaged Leafy Greens in Ontario, Canada

2013 ◽  
Vol 76 (2) ◽  
pp. 307-313 ◽  
Author(s):  
BRENT DIXON ◽  
LORNA PARRINGTON ◽  
ANGELA COOK ◽  
FRANK POLLARI ◽  
JEFFREY FARBER
Keyword(s):  
Dna Sequences ◽  
Giardia Duodenalis ◽  
The United States ◽  
Leafy Greens ◽  
High Prevalence ◽  
Cryptosporidium Oocysts ◽  
Foodborne Outbreaks ◽  
Parasite Viability ◽  
Assemblage B

Numerous foodborne outbreaks of diarrheal illness associated with the consumption of produce contaminated with protozoan parasites have been reported in North America in recent years. The present study reports on the presence of Cyclospora, Cryptosporidium, and Giardia in precut salads and leafy greens purchased at retail in Ontario, Canada. A total of 544 retail samples were collected between April 2009 and March 2010 and included a variety of salad blends and individual leafy greens. Most of these products were grown in the United States, with some from Canada and Mexico. Parasites were eluted and concentrated before detection by PCR and immunofluorescence microscopy. DNA sequences were aligned with reference sequences in GenBank. Cyclospora spp. were identified by PCR–restriction fragment length polymorphism in nine (1.7%) samples and by DNA sequence analysis. Cryptosporidium spp. were identified in 32 (5.9%) samples; 29 were sequenced and aligned with the zoonotic species Cryptosporidium parvum. Giardia duodenalis was identified in 10 (1.8%) samples, and of the 9 samples successfully sequenced, 7 aligned with G. duodenalis assemblage B and 2 with assemblage A, both of which are also zoonotic. The presence of Cryptosporidium oocysts and Giardia cysts was confirmed in some of the PCR-positive samples using microscopy, while Cyclospora-like oocysts were observed in most of the Cyclospora PCR-positive samples. The relatively high prevalence of these parasites in packaged salads and leafy greens establishes a baseline for further studies and suggests a need for additional research with respect to the possible sources of contamination of these foods, the determination of parasite viability and virulence, and means to reduce foodborne transmission to humans.

scholarly journals Molecular Characterization of Giardia duodenalis in Children and Adults Sampled in Algeria

2020 ◽  
Vol 9 (1) ◽  
pp. 54
Author(s):  
Salem Belkessa ◽  
Daniel Thomas-Lopez ◽  
Karim Houali ◽  
Farida Ghalmi ◽  
Christen Rune Stensvold
Keyword(s):  
Real Time ◽  
Molecular Characterization ◽  
Real Time Pcr ◽  
Intestinal Parasites ◽  
Giardia Duodenalis ◽  
Specific Pcr ◽  
Stool Samples ◽  
Pcr Targeting ◽  
Assemblage B

The molecular epidemiology of giardiasis in Africa remains unclear. A study was carried out across four hospitals in Algeria. A total of 119 fecal samples from 55 children, 37 adults, and 27 individuals of undetermined age, all scored positive for intestinal parasites by microscopy, and were screened by real-time PCR for Giardia. Molecular characterization of Giardia was performed by assemblage-specific PCR and PCR targeting the triose phosphate isomerase gene (tpi). Of the 119 samples, 80 (67%) were Giardia-positive by real-time PCR. For 48 moderately-highly real-time PCR-positive samples, tpi genotyping assigned 22 samples to Assemblage A and 26 to Assemblage B. Contrary to Assemblage A, Assemblage B exhibited substantial genetic diversity and allelic heterozygosity. Assemblage-specific PCR proved to be specific for discriminating Assemblage A or B but not as sensitive as tpi genotyping. We confirmed that real-time PCR is more sensitive than microscopy for detecting Giardia in stool samples and that robust amplification and sequencing of the tpi gene is feasible when moderate-to-strongly real-time PCR-positive samples are used. This study is one of the few performed in Africa providing genotyping data on Giardia infections in humans. Both assemblages A and B were commonly seen and not associated with specific sociodemographic data.

Epidemiology of an intestinal parasite (Spirometra spp.) in two populations of African lions (Panthera leo)

Parasitology ◽  
1999 ◽  
Vol 118 (4) ◽  
pp. 407-415 ◽  
Author(s):  
C. D. M. MÜLLER-GRAF ◽  
M. E. J. WOOLHOUSE ◽  
C. PACKER
Keyword(s):  
Intestinal Parasite ◽  
Infection Intensity ◽  
Ecological Factors ◽  
Parasite Infection ◽  
Panthera Leo ◽  
Age Classes ◽  
Intensity Of Infection ◽  
Faecal Samples ◽  
African Lions ◽  
Two Populations

Infection with the cestode Spirometra spp. was studied in 2 populations of lions in the Serengeti and the Ngorongoro Crater in Tanzania, East Africa. These 2 lion populations lived in different habitats and were known to differ genetically: lions in the Serengeti were outbred, whereas lions in the Ngorongoro Crater were inbred. Faecal samples were collected from 112 individually known lions between March 1991 and November 1992. Over 60% of lions were infected and the median intensity of infection was 975 eggs per g of faeces. The distribution of egg counts was overdispersed. There was variability through time, though this was unrelated to seasons delimited by rainfall. There were no significant differences in levels of infection between age classes; cubs less than 9 months were already heavily infected. Sex and reproductive status did not have a significant effect. However, there were significant differences in intensities of infection between the Crater and the Serengeti populations – Spirometra spp. showed a higher level of infection intensity in the Crater population – with some variation between prides within these populations. Allozyme heterozygosity scores were available for a subset of 28 lions but were unrelated to levels of Spirometra infection. It was not possible to ascribe differences in levels of parasite infection to genetic rather than ecological factors.

OBSERVATIONS ON THE EFFECTS OF VARIOUS SEWAGE TREATMENT PROCESSES UPON EGGS OF TAENIA SAGINATA1

1949 ◽  
Vol 49 (2) ◽  
pp. 166-175 ◽  
Author(s):  
WALTER L. NEWTON ◽  
HARRY J. BENNETT ◽  
WILLIAM B. FIGGAT
Keyword(s):  
Sewage Treatment ◽  
Treatment Processes

scholarly journals Occurrence of Giardia cysts and Cryptosporidium oocysts in activated sludge samples in Campinas, SP, Brazil

2004 ◽  
Vol 46 (6) ◽  
pp. 309-313 ◽  
Author(s):  
Luciana Urbano Santos ◽  
Taís Rondello Bonatti ◽  
Romeu Cantusio Neto ◽  
Regina Maura Bueno Franco
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
High Concentration ◽  
Potential Source ◽  
Two Samples ◽  
Cryptosporidium Oocysts ◽  
Flotation Method ◽  
Giardia Cysts

Giardia and Cryptosporidium have caused several outbreaks of gastroenteritis in humans associated with drinking water. Contaminated sewage effluents are recognized as a potential source of waterborne protozoa. Due to the lack of studies about the occurrence of these parasites in sewage samples in Brazil, we compared the efficiency of two procedures for concentrating cysts and oocysts in activated sludge samples of one sewage treatment plant. For this, the samples were submitted to i) concentration by the ether clarification procedure (ECP) and to ii) purification by sucrose flotation method (SFM) and aliquots of the pellets were examined by immunofluorescence. Giardia cysts were present in all samples (100.0%; n = 8) when using ECP and kit 1 reagents, while kit 2 resulted in six positive samples (85.7%; n = 7). As for SFM, cysts were detected in 75.0% and 100.0% of these samples (for kit 1 and 2, respectively). Regarding Cryptosporidium, two samples (25.0%; kit 1 and 28.5% for kit 2) were detected positive by using ECP, while for SFM, only one sample (examined by kit 1) was positive (12.5%). The results of the control trial revealed Giardia and Cryptosporidium recovery efficiency rates for ECP of 54.5% and 9.6%, while SFM was 10.5% and 3.2%, respectively. Considering the high concentration detected, a previous evaluation of the activated sludge before its application in agriculture is recommended and with some improvement, ECP would be an appropriate simple technique for protozoa detection in sewage samples.

Comparison of six different sewage treatment processes—Reduction of estrogenic substances and effects on gene expression in exposed male fish

2009 ◽  
Vol 407 (19) ◽  
pp. 5235-5242 ◽  
Author(s):  
L. Gunnarsson ◽  
M. Adolfsson-Erici ◽  
B. Björlenius ◽  
C. Rutgersson ◽  
L. Förlin ◽  
...  
Keyword(s):  
Gene Expression ◽  
Sewage Treatment ◽  
Male Fish ◽  
Treatment Processes

scholarly journals Distribution and Removal of Pharmaceuticals in Liquid and Solid Phases in the Unit Processes of Sewage Treatment Plants

2020 ◽  
Vol 17 (3) ◽  
pp. 687 ◽  
Author(s):  
Junwon Park ◽  
Changsoo Kim ◽  
Youngmin Hong ◽  
Wonseok Lee ◽  
Hyenmi Chung ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Biological Treatment ◽  
Sewage Treatment ◽  
Biofilm Reactor ◽  
Relative Distribution ◽  
Biological Processes ◽  
Sewage Treatment Plants ◽  
Treatment Processes ◽  
Mass Load ◽  
Removal Efficiencies

In this study, we analyzed 27 pharmaceuticals in liquid and solid phase samples collected from the unit processes of four different sewage treatment plants (STPs) to evaluate their distribution and behavior of the pharmaceuticals. The examination of the relative distributions of various categories of pharmaceuticals in the influent showed that non-steroidal anti-inflammatory drugs (NSAIDs) were the most dominant. While the relative distribution of antibiotics in the influent was not high (i.e., 3%–5%), it increased to 14%–30% in the effluent. In the four STPs, the mass load of the target pharmaceuticals was reduced by 88%–95% mainly in the biological treatment process, whereas the ratio of pharmaceuticals in waste sludge to those in the influent (w/w) was only 2%. In all the STPs, the removal efficiencies for the stimulant caffeine, NSAIDs (acetaminophen, naproxen, and acetylsalicylic acid), and the antibiotic cefradine were high; they were removed mainly by biological processes. Certain compounds, such as the NSAID ketoprofen, contrast agent iopromide, lipid regulator gemfibrozil, and antibiotic sulfamethoxazole, showed varying removal efficiencies depending on the contribution of biodegradation and sludge sorption. In addition, a quantitative meta-analysis was performed to compare the pharmaceutical removal efficiencies of the biological treatment processes in the four STPs, which were a membrane bioreactor (MBR) process, sequencing batch reactor (SBR) process, anaerobic–anoxic–oxic (A2O) process, and moving-bed biofilm reactor (MBBR) process. Among the biological processes, the removal efficiency was in the order of MBR > SBR > A2O > MBBR. Among the tertiary treatment processes investigated, powdered activated carbon showed the highest removal efficiency of 18%–63% for gemfibrozil, ibuprofen, ketoprofen, atenolol, cimetidine, and trimethoprim.

Nutrient reduction evaluation of sewage effluent treatment options for small communities

2005 ◽  
Vol 51 (10) ◽  
pp. 221-229 ◽  
Author(s):  
P.D. Beavers ◽  
I.K. Tully
Keyword(s):  
Total Nitrogen ◽  
Sewage Treatment ◽  
Subsurface Flow ◽  
Primary Objective ◽  
Effluent Treatment ◽  
Sand Filter ◽  
Small Communities ◽  
Treatment Processes ◽  
Treated Effluent ◽  
Slow Sand Filter

Small communities that are sewered by either package sewage treatment plants or on-site sewerage facilities are finding that the ground and surface waters are being contaminated. Nitrogen, which typically is not removed in these conventional systems, is a major concern. This project evaluated the capability of four sewage treatment technologies to reduce the amount of nitrogen being discharged in the effluent to the receiving environment. The four sewage treatment processes evaluated include a recirculating sand filter, biofilter, slow sand filter and constructed subsurface flow wetland. These processes were evaluated for their capability to reduce nitrogen, phosphorus, BOD5 and TSS. The primary objective of the project was to evaluate the capability of these treatment processes to reduce nitrogen using biological processes nitrification and denitrification. This paper reports on the performance of these processes to reduce nitrogen. The study demonstrated that the biofilter was capable of removing from a primary treated influent 40% of the total nitrogen. For the same quality influent the recirculating sand filter was capable of removing 35% of the total nitrogen. Secondary treated effluent was fed to the slow sand filter and the subsurface flow wetland. There was a 52% reduction in total nitrogen through the wetland however there was virtually no reduction in total nitrogen through the slow sand filter.

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