Effect of Glycosaminoglycans on Oocyst Attachment and Excystation.

causes severe gastrointestinal disease resulting from the ingestion of oocysts, followed by oocyst excystation in the small intestine and the release of infective sporozoites. An understudied strategy for inactivation is purposeful oocyst excystation, as sporozoites do not survive long in the environment. This study showed that C.

Development of cell-imprinted polymer surfaces for Cryptosporidium capture and detection.

Cryptosporidium parvum is waterborne parasite that can cause potentially life-threatening gastrointestinal disease and is resistant to conventional water treatment processes, including chlorine disinfection. The current Environmental Protection Agency-approved method for oocyst detection and quantification is expensive, limiting the ability of water utilities to monitor complex watersheds thoroughly to understand the fate and transport of C. parvum oocysts.

Making Waves: Collaboration in the time of SARS-CoV-2 - rapid development of an international co-operation and wastewater surveillance database to support public health decision-making.

The presence of SARS-CoV-2 RNA in wastewater was first reported in March 2020. Over the subsequent months, the potential for wastewater surveillance to contribute to COVID-19 mitigation programmes has been the focus of intense national and international research activities, gaining the attention of policy makers and the public. As a new application of an established methodology, focused collaboration between public health practitioners and wastewater researchers is essential to developing a common understanding on how, when and where the outputs of this non-invasive community-level approach can deliver actionable outcomes for public health authorities.

Influence of sand depth and pause period on microbial removal in traditional and modified biosand filters.

Three different-sized biosand filters (i.e., the center for Affordable Water and Sanitation Technology v10 concrete filter, a 5-gal bucket filter, and a 2-gal bucket filter with fine sand depths of 54, 15, and 10 cm, respectively), configured with and without the addition of iron nails to the diffuser basin, were evaluated for removal of bacteria, protozoa, and viruses over pause periods ranging from 1 to 72 hrs.

Biofilm Sampling for Detection of Oocysts in a Southeastern Pennsylvania Watershed.

This study investigated the use of biofilms to monitor in water. Benthic rock and submersible slide biofilms were sampled upstream and downstream of point sources in a suburban watershed in southeastern Pennsylvania. More oocysts were detected in biofilms scraped from rocks downstream than upstream of a wastewater treatment plant (WWTP) (19 versus 5, respectively;  = 1).

Evaluation of consistent use, barriers to use, and microbiological effectiveness of three prototype household water treatment technologies in Haiti, Kenya, and Nicaragua.

Household water treatment (HWT) can improve drinking water quality and reduce diarrheal disease. New HWT technologies are typically evaluated under ideal conditions; however, health gains depend on consistent, effective household use, which is less often evaluated. We conducted four evaluations of three prototype HWT technologies: two filters and one electrochlorinator.

Calcium-Mediated Biophysical Binding of Cryptosporidium parvum Oocysts to Surfaces Is Sensitive to Oocyst Age.

causes potentially life-threatening gastrointestinal disease in humans and may not be effectively removed from drinking water via conventional methods. Prior research has shown that environmental biofilms immobilize oocysts from the water column, but the biophysical mechanisms driving this attraction are still under investigation. This study investigates the affinity of oocysts to silanized surfaces.

Role of Wall Shear Stress in Cryptosporidium parvum Oocyst Attachment to Environmental Biofilms.

This study investigated oocyst deposition onto biofilms as a function of shear stress under laminar or turbulent flow. Annular rotating bioreactors were used to grow stabilized stream biofilms at shear stresses ranging from 0.038 to 0.

Effect of Sand Bed Depth and Medium Age on Escherichia coli and Turbidity Removal in Biosand Filters.

The main objective of this study was to build several full-scale biosand filters (BSFs) and assess the long-term (9 month) efficacy for particulate and Escherichia coli removal under simulated real-world usage. Four replicates of three different filter designs were built: the traditional concrete BSF and two scaled-down versions that use a 5 or 2 gal bucket as the casing material. The smaller sand bed depths in the bucket-sized filters did not impact filter performance with respect to (i) turbidity and E.

Pseudo-Second-Order Calcium-Mediated Cryptosporidium parvum Oocyst Attachment to Environmental Biofilms.

Unlabelled: Cryptosporidium parvum oocysts are able to infect a wide range of mammals, including humans, via fecal-oral transmission. The remobilization of biofilm-associated C. parvum oocysts back into the water column by biofilm sloughing or bulk erosion poses a threat to public health and may be responsible for waterborne outbreaks; thus, the investigation of C.

Impact of Bioreactor Environment and Recovery Method on the Profile of Bacterial Populations from Water Distribution Systems.

Multiple rotating annular reactors were seeded with biofilms flushed from water distribution systems to assess (1) whether biofilms grown in bioreactors are representative of biofilms flushed from the water distribution system in terms of bacterial composition and diversity, and (2) whether the biofilm sampling method affects the population profile of the attached bacterial community. Biofilms were grown in bioreactors until thickness stabilized (9 to 11 weeks) and harvested from reactor coupons by sonication, stomaching, bead-beating, and manual scraping. High-throughput sequencing of 16S rRNA amplicons was used to profile bacterial populations from flushed biofilms seeded into bioreactors as well as biofilms recovered from bioreactor coupons by different methods.

Transport effects on hydraulic loading rate and microbial removal performance in biosand filters.

Biosand filters (BSFs) are increasingly designed using smaller and/or lighter casing material in an effort to reduce logistical requirements and implementation costs. The increased portability of a smaller, lighter design presents a potential negative consequence: the ability to move the installed/operational filter by the homeowner and potentially disturb the system. This study investigated the effects of moving and agitation on filter performance, using mature BSFs which had been in use for over nine months prior to the move.

Emergency water treatment with bleach in the United States: the need to revise EPA recommendations.

During emergencies in the United States, the Environmental Protection Agency (EPA) currently recommends using bottled water, or boiling or treating water by adding 1/8 teaspoon (or 8 drops) of bleach to 1 gal of water. This bleach recommendation is internally inconsistent, a relatively high chlorine dose (5.55-8.

Effect of production variables on microbiological removal in locally-produced ceramic filters for household water treatment.

Diarrhoeal diseases cause an estimated 1.87 million child deaths per year. Point-of-use filtration using locally made ceramic filters improves microbiological quality of stored drinking water and prevents diarrhoeal disease.

Turbidity and chlorine demand reduction using alum and moringa flocculation before household chlorination in developing countries.

Over 1.1 billion people in the world lack access to improved drinking water. Diarrhoeal and other waterborne diseases cause an estimated 1.

Source tracking identifies deer and geese as vectors of human-infectious Cryptosporidium genotypes in an urban/suburban watershed.

This study identified Cryptosporidium genotypes in the Wissahickon watershed from May 2005 to April 2008. We analyzed 129 samples from Wissahickon Creek, 83 effluent samples from wastewater treatment plants (WWTPs), and 240 fecal droppings. Genotyping was based on the hypervariable region of the 18S rRNA gene.

Turbidity and chlorine demand reduction using locally available physical water clarification mechanisms before household chlorination in developing countries.

Over 1.1 billion people in the world lack access to improved drinking water. Diarrhoeal and other waterborne diseases cause an estimated 1.

Artificial UV-B and solar radiation reduce in vitro infectivity of the human pathogen Cryptosporidium parvum.

The potential for solar ultraviolet (UV) radiation to act as a significant abiotic control of Cryptosporidium parvum oocysts in nature is unknown. Infectivity of C. parvum following exposure to artificial UV-B and natural solar radiation, with and without UV wavelengths, was tested under controlled pH and temperature conditions.

Phylogenetic analysis implicates birds as a source of Cryptosporidium spp. oocysts in agricultural watersheds.

Cryptosporidium parvum and C. hominis are protozoan parasites responsible for cryptosporidiosis, an acute gastrointestinal illness that can be life-threatening for immunocompromised persons. Sources and genotypes of Cryptosporidium oocysts were investigated in two agricultural areas within the Wachusett Reservoir watershed, a drinking water source for Boston, Massachusetts.

Phylogenetic analysis of the hypervariable region of the 18S rRNA gene of Cryptosporidium oocysts in feces of Canada geese (Branta canadensis): evidence for five novel genotypes.

To assess genetic diversity in Cryptosporidium oocysts from Canada geese, 161 fecal samples from Canada geese in the United States were analyzed. Eleven (6.8%) were positive for Cryptosporidium spp.

Sources and species of cryptosporidium oocysts in the Wachusett Reservoir watershed.

Understanding the behavior of Cryptosporidium oocysts in the environment is critical to developing improved watershed management practices for protection of the public from waterborne cryptosporidiosis. Analytical methods of improved specificity and sensitivity are essential to this task. We developed a nested PCR-restriction fragment length polymorphism assay that allows detection of a single oocyst in environmental samples and differentiates the human pathogen Cryptosporidium parvum from other Cryptosporidium species.