Occurrence Of Cryptosporidium Research Articles

Occurrence of Cryptosporidium and Giardia in raw and finished drinking water in north-eastern Spain.

This paper collects the first large-sample-size study on the presence of Cryptosporidium oocysts and Giardia cysts in drinking water plants at the 20 most populated towns in Aragón (north-eastern Spain). Samples of influent raw water and effluent finished water were collected from each plant during different seasons and processed according to USEPA Method 1623. Cryptosporidium oocysts and Giardia cysts were detected in samples collected from 55% and 70% plants, respectively, with nine plants being positive for both protozoa and only four plants being negative over the study period. Both parasites were identified in the raw water throughout the year, with a lower frequency in autumn and a peak in winter, at a mean concentration of 67±38 oocysts per 100l and 125±241 cysts per 100l. The turbidity of raw water was not related to the presence or concentration of (oo)cysts, and the (oo)cyst removal efficiency was not related to the type of water treatment. One or both pathogens were identified in the finished water in 7 out of 11 plants with a conventional treatment process (coagulation, flocculation, sedimentation, filtration, and disinfection processes) compared to 4 out of 9 plants that did not apply one of the pre-chlorination treatment steps. Protozoa were detected in the finished water of positive plants at a mean concentration of 88±55 oocysts per 100l and 37±41 cysts per 100l, and most of them excluded propidium iodide so were considered potentially viable. The ubiquity of these parasites in the drinking water sources and the inefficiency of conventional water treatment in reducing/inactivating them may present a serious public health issue in this geographical area.

Occurrence of Cryptosporidium spp. and Giardia spp. in pigs at weaning

Cryptosporidium spp. and Giardia spp. are parasites and have been reported in many species of mammals, including humans. The goal of this research was to investigate the occurrence of Cryptosporidium spp. and Giardia spp. in 45-days-old pigs. Fecal samples of 107 pigs were collected at three alternate days in piggeries in Araçatuba, São Paulo State, Brazil. Cryptosporidium oocysts were observed in 4.7% (5/107) of animals by Kinyoun acid-fast stain method and cysts of Giardia spp. were observed in 1.9% (2/107) of the animals by the method of Faust. Of all animals, 85 presented feces with normal consistency and 22 showed diarrhea in at least one collection. Two diarrheic samples showed positivity for both Cryptosporidium spp. and Giardia spp. From these results it is possible to infer that the occurrence of Cryptosporidium and Giardia was low because of the good management practices and both protozoa were not associated the presence of symptoms.

Prevalence and genetic characterization of Cryptosporidium species and Giardia duodenalis in lambs in Oromia Special Zone, Central Ethiopia.

Background Cryptosporidium and Giardia duodenalis are gastro-intestinal parasites that infect human and animals worldwide. Both parasites share a broad host range and are believed to be zoonosis. The aim of this study was to identify the species of Cryptosporidium and assemblages of G. duodenalis in lambs and to elucidate their role in zoonotic transmission.ResultsA total of 389 fecal samples were collected from lambs and screened by microscopy and nested PCR targeting the small-subunit ribosomal RNA for Cryptosporidium; and the small-subunit ribosomal RNA, triose phosphate isomerase, β-giardin, and glutamate dehydrogenase genes for G. duodenalis. The prevalence of Cryptosporidium and G. duodenalis was 2.1% (8/389) and 2.6% (10/389), respectively. The infection rate at the three study sites ranged from 1.3 to 3.1% for Cryptosporidium and 1.6 to 3.9% for G. duodenalis; but variation was not statistically significant (p > 0.05). The finding also showed that there is no sex and age group associated difference in the occurrence of Cryptosporidium and G. duodenalis infections in lambs. Sequence analysis revealed that lambs were mono-infection with C. ubiquitum and G. duodenalis assemblage E. The analysis also indicated the presence of genetic variation within isolates of assemblage E; with 4 of them are novel genotypes at the small-subunit ribosomal RNA, β-giardin, and glutamate dehydrogenase genes.ConclusionThe findings of the current study showed that lambs are capable of harboring C. ubiquitum and G. duodenalis assemblage E. This finding suggests that lambs might be sources for potentially zoonotic Cryptosporidium species. This was first molecular study in lambs and contributes to a better understanding of the epidemiology of Cryptosporidium and G. duodenalis in central Ethiopia.

Cryptosporidium spp. and Enterocytozoon bieneusi in introduced raccoons (Procyon lotor)-first evidence from Poland and Germany.

The raccoon (Procyon lotor) carnivore native to North America is a fast spreading, invasive species in the Europe now. At the moment, the highest population occupies areas near the German-Polish border. The data on the occurrence of Cryptosporidium spp. and microsporidia in raccoons is limited to North America’s territory and is totally lacking in the case of their introduction to Europe. Therefore, the objective of this study was to investigate the occurrence of microparasites, i.e., Cryptosporidium spp. and microsporidia in the introduced raccoons obtained from localities in Poland and Germany. A PCR-based approach that permitted genetic characterization via sequence analysis was applied to raccoon fecal samples (n = 49), collected during 2012–2014. All fecal samples were simultaneously tested with the use of genetic markers, and DNA of microsporidia and Cryptosporidium spp. was detected among the examined raccoons. The results of our research confirmed the presence of Cryptosporidium skunk genotype and Enterocytozoon bieneusi NCF2 genotype. The results suggest a possible role of raccoons in the contamination of the environment, including urban areas, with pathogens of zoonotic significance as well as their role in the transmission and introduction of new genotypes of microparasites in the areas where P. lotor has not been observed yet. To our knowledge, there has been no literature data on the above genotypes detected previously in humans or animals from the examined study sites so far.

Towards a more accurate quantitative assessment of seasonal Cryptosporidium infection risks in surface waters using species and genotype information

Many Cryptosporidium species/genotypes are not considered infectious to humans, and more realistic estimations of seasonal infection risks could be made using human infectious species/genotype information to inform quantitative microbial risk assessments (QMRA). Cryptosporidium oocyst concentration and species/genotype data were collected from three surface water surveillance programs in two river basins [South Nation River, SN (2004-09) and Grand River, GR (2005-13)] in Ontario, Canada to evaluate seasonal infection risks. Main river stems, tributaries, agricultural drainage streams, water treatment plant intakes, and waste water treatment plant effluent impacted sites were sampled. The QMRA employed two sets of exposure data to compute risk: one assuming all observed oocysts were infectious to humans, and the other based on the fraction of oocysts that were C. hominis and/or C. parvum (dominant human infectious forms of the parasite). Viability was not considered and relative infection risk was evaluated using a single hypothetical recreational exposure. Many sample site groupings for both river systems, had significant seasonality in Cryptosporidium occurrence and concentrations (p ≤ 0.05); occurrence and concentrations were generally highest in autumn for SN, and autumn and summer for GR. Mean risk values (probability of infection per exposure) for all sites combined, for each river system, were roughly an order of magnitude lower (avg. of SN and GR 5.3 × 10−5) when considering just C. parvum and C. hominis oocysts, in relation to mean infection risk (per exposure) assuming all oocysts were infectious to humans (5.5 × 10−4). Seasonality in mean risk (targeted human infectious oocysts only) was most strongly evident in SN (e.g., 7.9 × 10−6 in spring and 8.1 × 10−5 in summer). Such differences are important if QMRA is used to quantify effects of water safety/quality management practices where inputs from a vast array of fecal pollution sources can readily occur. Cryptosporidium seasonality in water appears to match the seasonality of human infections from Cryptosporidium in the study regions. This study highlights the importance of Cryptosporidium species/genotype data to help determine surface water pollution sources and seasonality, as well as to help more accurately quantify human infection risks by the parasite.

Caracterização molecular de Cryptosporidium spp. em criações comerciais brasileiras de coelhos

RESUMO A criptosporidiose é uma importante zoonose que pode ser transmitida por meio de alimentos, água de bebida e por contato com animais e pessoas infectadas. Além disso, trata-se de uma enfermidade clínica ou subclínica frequente em diversas espécies de animais, incluindo coelhos domésticos. O objetivo deste estudo foi determinar a ocorrência de Cryptosporidium spp., realizar sua classificação molecular e relacionar a presença do parasito às diferentes fases de criação em 21 criações comerciais de coelhos, localizadas nos estados de Minas Gerais, Mato Grosso do Sul, Pernambuco, Paraná, Rio de Janeiro, Rio Grande do Sul e São Paulo. Quinhentas e catorze amostras de fezes foram colhidas e armazenadas em solução de dicromato de potássio 5%. Os oocistos foram purificados por centrífugo-flutuação em solução de Sheather e visualizados por microscopia, utilizando-se a coloração negativa com verde malaquita. Cinquenta e cinco amostras foram submetidas à reação em cadeia pela polimerase (nested PCR) e ao sequenciamento de fragmentos amplificados, referentes aos genes da subunidade 18S do rRNA e da glicloproteína GP60, visando à caracterização molecular de Cryptosporidium spp. Oito amostras foram positivas para Cryptosporidium spp. pela microscopia (1,56%; 8/514) e sete foram positivas pela nested PCR (12,73%; 7/55). Pela análise molecular, foi possível identificar Cryptosporidium cuniculus (18S rRNA) e C. cuniculus subtipo VbA21 (gp60) em coelhos jovens e em matrizes.

Detection of Cryptosporidium hominis and novel Cryptosporidium bat genotypes in wild and captive Pteropus hosts in Australia

Spillover of zoonotic pathogens from wildlife to humans has been identified as a primary threat to global health. In contrast, the process of reverse pathogen transmission (zooanthroponosis), whereby pathogens move from humans into wildlife species is still largely unexplored. Globally, increasing urbanisation and habitat loss are driving many wildlife species into urban and regional centres. In Australia, large numbers of flying foxes now live in close proximity to humans, increasing the risk of zooanthroponosis. The protozoan parasite Cryptosporidium is an emerging zoonotic parasite that infects a wide range of vertebrates yet there are limited studies on transmission potential of Cryptosporidium between humans and urban wildlife. To explore the presence of zooanthroponosis in flying foxes in Australia the occurrence and diversity of Cryptosporidium was investigated in urbanised wild and captive flying foxes. PCR screening of faecal samples (n=281) from seven wild sites and two captive facilities identified the presence of Cryptosporidium in 3.2% (95% CI 1.5% to 6.0%) of faecal samples. In faecal samples from wild sites Cryptosporidium occurrence was 1.7% (95% CI 0.3% to 4.8%) versus 5.9% (95% CI 2.2% to 12.4%) in samples from captive individuals, with no significant difference between captive and wild sites (p=0.077). Multilocus sequencing using three loci, 18s rDNA, actin and gp60 was used to identify Cryptosporidium in flying fox species. The host specific Cryptosporidium hominis was identified in faecal samples from two captive flying foxes, and one of these samples was confirmed as C. hominis at both actin and gp60. Sequencing of the 18s rDNA also revealed four novel Cryptosporidium genotypes in wild and captive individuals, actin and gp60 amplification and sequencing were unreliable for all four novel genotypes. These novel genotypes have been designated Cryptosporidium bat genotypes VIII–XI. This first report of Cryptosporidium spp. in Australian flying foxes indicates zooanthroponotic transmission of Cryptosporidium from humans to flying foxes within a captive environment and extends the diversity of this globally important parasite.

Prevalence and molecular characterization of Cryptosporidium species in cattle and buffalo calves in Mumbai region of India

Faecal samples of cattle and buffaloes of Mumbai region collected between November 2012 to June 2013 were analysed by conventional and molecular tools to note the prevalence of cryptosporidiosis and species involved in the infection. Conventional analysis viz., direct faecal smear examination, faecal smear examination after normal saline sedimentation, Sheather's floatation and Sheather's floatation sedimentation smear methods demonstrated oocysts of Cryptosporidium in 141 (36.06%) of 391 samples with higher occurrence in buffaloes (36.99%) than cattle (34.48%). Diarrhoeic loose faeces showed higher prevalence (42.07%) than apparently normal faeces (31.72%) irrespective of the host species. When data were arranged as per age groups viz., calves of 0-1month, 1-2months, 2-3months and adults, the highest prevalence was noted in the youngest group (47.12%) declining gradually with the advancing age with lowest (6.25%) in adults indicating inverse correlation between prevalence rate and age of the host. These differences were statistically significant in case of buffaloes. Cryptosporidium andersoni was tentatively identified by morphometric analysis. By employing molecular tools like nested PCR, PCR-RFLP and sequence analysis of few samples showed good correlation in the identification of species of Cryptosporidium involved in the infection and demonstrated occurrence of C. parvum, C. ryanae and C. bovis. Thus all the four commonly occurring bovine species of Cryptosporidium were encountered in the study area which appears to be a first record reporting the occurrence of Cryptosporidium with species level identification in large ruminants from Western region of India. Additionally, the public health significance of C. parvum was also discussed in light of epidemiological factors pertaining to the region.

Identification of Cryptosporidium from Dairy Cattle in Pahang, Malaysia.

Cryptosporidium, a protozoan parasite, can cause cryptosporidiosis which is a gastrointestinal disease that can infect humans and livestock. Cattle are the most common livestock that can be infected with this protozoan. This study was carried out to determine the prevalence of Cryptosporidium infection in cattle in Kuantan, Pahang, Malaysia and to find out the association between the occurrence of infection and 3 different ages of cattle (calves less than 1 year, yearling, and adult cattle). The samples were processed by using formol-ether concentration technique and stained by modified Ziehl Neelsen. The results showed that 15.9% (24/151) of cattle were positive for Cryptosporidium oocysts. The occurrence of Cryptosporidium in calves less than 1 year was the highest with the percentage of 20.0% (11/55) followed by yearling and adult cattle, with the percentage occurrence of 15.6 % (7/45) and 11.8% (6/51), respectively. There was no significant association between the occurrence and age of cattle and presence of diarrhea. Good management practices and proper hygiene management must be taken in order to reduce the infection. It is highly important to control the infection since infected cattle may serve as potential reservoirs of the infection to other animals and humans, especially animal handlers.

Cryptosporidium in Wastewater: Occurrence, Removal and Inactivation

This study focused on one pathogen, Cryptosporidium parvum, and its occurrence in wastewater. In order to conduct an occurrence study, it was firstly necessary to develop methods for recovery of Cryptosporidium oocysts from wastewater matrices. Due to the differences in matrix composition from raw sewage to tertiary effluents, different methods for recovery and enumeration of oocysts were developed based on matrix quality.A single method was developed for raw sewage and primary influents; a second method for secondary and tertiary effluents; and a third method for biosolids. These methods were used in a survey of Cryptosporidium occurrence at 10 wastewater plants in the U.S. over a 15-month period. To determine if oocysts found in wastewater samples represented a public health risk, cell culture methods were employed to examine infectivity of recovered oocysts.This title belongs to WERF Research Report SeriesISBN: 9781843397182 (Print)ISBN: 9781780404417 (eBook)

Sources and Variability of Cryptosporidium in the Milwaukee River Watershed

Recent well-publicized waterborne Cryptosporidium outbreaks involving large numbers of ill people and some deaths have been attributed to possible treatment deficiencies linked with source water (watershed) contamination. Understanding the occurence and variability of Cryptosporidium in a watershed is critical to the production of a safe drinking water supply. Essential to this understanding is the ability to characterize potential sources of Cryptosporidium and predict their occurrence in a watershed. The purpose of the work described in this report is to define the relative magnitude and contributions of Cryptosporidium from major non-point sources defined by urban land use, rural land use and point source wastewater discharges and to characterize contributions of each source by factors such as hydrograph timing, climatic effects and seasonal variations. Statistical models are presented that can be used to estimate the probability of high Cryptosporidium levels from a given combination of conditions and may be useful for maximising sampling strategies for watershed managers charged with understanding Cryptosporidium occurrence in a watershed. This title belongs to WERF Research Report Series ISBN: 9781843396659 (Print) ISBN: 9781780404035 (eBook)

Occurrence of Cryptosporidium spp. in wild animals living in the Cascavel city park, Paraná, Brazil

<p>Digestive and respiratory tracts parasite’s protozoan, <em>Cryptosporidium </em>spp. now-a-days is a major zoonotic agent, it causes self-limiting diarrhea, remaining in the body passively until the moment immune system decreases, leading to an increase in its multiplication in the mucosa and appearance of clinical signs. As there are few studies on cryptosporidiosis in wild free-living and captive animals, especially in Brazil, this study aimed to identify the presence of <em>Cryptosporidium </em>spp. in feces of captive animals in Cascavel, PR Municipal Zoo. Between 2011 and 2012 there have been four collections of bird feces and five mammalian feces totaling 65 and 118 samples respectively. Samples were sent to the laboratory of Veterinary Parasitology of Federal University of Parana. The feces were diluted, centrifuged and the pellets were used to make blades which were stained by the Ziehl-Neelsen modified method and observed under a microscope with 1000X magnification. Then the blades containing the oocysts were observed under a capture microscope, where they were measured. Mammals showed 49.15% and birds 44.61% of positivity. Oocysts’ sizes ranged from 3,54?m to 5,81?m with an average of 4,32?m for birds and 3,11?m to 5,60?m averaging 4,63?m to mammals. As of yet, there isn’t effective treatment against this parasite and considering that it’s a zoonotic disease, preventive measures should be taken to prevent transmission to humans.</p>

Occurrence of Cryptosporidium spp. in wild animals living in the Cascavel city park, Paraná, Brazil

Digestive and respiratory tracts parasite’s protozoan, Cryptosporidium spp. now-a-days is a major zoonotic agent, it causes self-limiting diarrhea, remaining in the body passively until the moment immune system decreases, leading to an increase in its multiplication in the mucosa and appearance of clinical signs. As there are few studies on cryptosporidiosis in wild free-living and captive animals, especially in Brazil, this study aimed to identify the presence of Cryptosporidium spp. in feces of captive animals in Cascavel, PR Municipal Zoo. Between 2011 and 2012 there have been four collections of bird feces and five mammalian feces totaling 65 and 118 samples respectively. Samples were sent to the laboratory of Veterinary Parasitology of Federal University of Parana. The feces were diluted, centrifuged and the pellets were used to make blades which were stained by the Ziehl-Neelsen modified method and observed under a microscope with 1000X magnification. Then the blades containing the oocysts were observed under a capture microscope, where they were measured. Mammals showed 49.15% and birds 44.61% of positivity. Oocysts’ sizes ranged from 3,54?m to 5,81?m with an average of 4,32?m for birds and 3,11?m to 5,60?m averaging 4,63?m to mammals. As of yet, there isn’t effective treatment against this parasite and considering that it’s a zoonotic disease, preventive measures should be taken to prevent transmission to humans.

Detection of Cryptosporidium, Giardia, fecal Indicator bacteria, and total bacteria in commercial jar water in the Kathmandu Valley, Nepal

Introduction: Jar water is a convenient and common source of drinking water in the Kathmandu Valley. However, studies including detailed microbial analyses of this source of potable water are lacking. In this study, jar water samples were examined for the occurrence of Cryptosporidium, Giardia, fecal indicator bacteria, and total bacteria. Methods: Thirty different brands of jars were collected in September 2014. Escherichia coli and total coliforms were determined using a Colilert reagent. Ten of the 30 brands were selected to test for Cryptosporidium, Giardia, and total bacteria. Bacterial DNA extraction from water samples was performed using the Cica Geneus DNA Extraction Kit, followed by quantitative polymerase chain reaction (qPCR) targeting the 16S rRNA gene of bacterial DNA. Protozoan detection was accomplished by concentrating the samples using the electronegative membrane vortex method. followed by immunomagnetic separation and fluorescent staining. Results: E. coli was detected in 10% of the samples, with a maximum concentration of 2 most probable number (MPN)/100 ml., whereas total coliforms were detected in 97% of the samples, with a maximum and mean concentration of 7.3 x 102 and 3.8 x 10 MPN/100 ml., respectively. Total coliforms concentrations in 40% of the samples ranged from 10 to 10 MPN/100 ml. Cryptosporidium and Giardia were not detected in any of the tested samples. Concentrations of total bacteria in the samples ranged from 10 to 10 cells/100 ml. Conclusions: Ninety-seven percent of the jar water brands were unsuitable for drinking without proper treatment based on the guideline values of the National Drinking Water Quality Standards (NDWQS) of Nepal. There is no guideline value for total bacteria in NDWQS however, high concentrations can be indicative of poor control on regrowth of bacteria and recontamination or inefficient water treatment methods.

Occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system, Paraná, Southern Brazil.

The purpose of this study was to investigate the occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system. Samples of raw and treated water were collected and concentrated using the membrane filtration technique. Direct Immunofluorescence Test was performed on the samples. DNA extraction using a commercial kit was performed and the DNA extracted was submitted to a nested-PCR reaction (n-PCR) and sequencing. In the immunofluorescence, 2/24 (8.33%) samples of raw water were positive for Giardia spp.. In n-PCR and sequencing, 2/24 (8.33%) samples of raw water were positive for Giardia spp., and 2/24 (8.33%) samples were positive for Cryptosporidium spp.. The sequencing showed Cryptosporidium parvum and Giardia duodenalis DNA. In raw water, there was moderate correlation among turbidity, color and Cryptosporidium spp. and between turbidity and Giardia spp.. The presence of these protozoans in the water indicates the need for monitoring for water-treatment companies.

First Molecular Characterization of Cryptosporidium spp. Infecting Buffalo Calves in Brazil.

With the aim of determining the occurrence of Cryptosporidium spp., 222 fecal samples were collected from Murrah buffalo calves aged up to 6 mo. Fecal DNA was genotyped with a nested polymerase chain reaction targeting the 18S rRNA gene and sequencing of the amplified fragment. Nested 18S PCR was positive for 48.2% of the samples. Sequence analysis showed that the most frequent species in these animals was Cryptosporidium ryanae, which was present in buffalo calves as young as 5 d. The zoonotic species Cryptosporidium parvum was detected in one animal. An uncommon Cryptosporidium 18S genotype was found in buffaloes.

Zoonotic Cryptosporidium spp. and Enterocytozoon bieneusi in pet chinchillas (Chinchilla lanigera) in China

Cryptosporidium and Enterocytozoon bieneusi are the most prevalent protist pathogens responsible for inducing human and animal diseases worldwide. The aim of the present work was to determine the occurrence of Cryptosporidium spp. and E. bieneusi in pet chinchillas in China. One hundred forty fecal samples were collected from four cities: Beijing, Zhengzhou, Anyang and Guiyang. They were then examined with PCR amplification of the small subunit ribosomal RNA (SSU rRNA) of Cryptosporidium spp. and the internal transcribed spacer (ITS) of the ribosomal RNA of E. bieneusi. The infection rates for Cryptosporidium spp. and E. bieneusi were 10.0% and 3.6%, respectively. Sequence analysis of SSU rRNA gene products identified two Cryptosporidium spp., Cryptosporidium ubiquitum (n=13) and Cryptosporidium parvum (n=1). Subtyping with the 60-kDa glycoprotein (gp60) gene showed that all C. ubiquitum isolates belonged to zoonotic subtype family XIId, while the subtype of the C. parvum isolate could not be identified. Two E. bieneusi genotypes were identified in five samples, zoonotic genotypes BEB6 (n=3) and D (n=2). This is the first report of C. ubiquitum and C. parvum, and E. bieneusi in chinchillas. This result indicates that pet chinchillas may be a potential source of human infection with Cryptosporidium spp. and E. bieneusi.

Assessment of molecular methods as a tool for detecting pathogenic protozoa isolated from water bodies

Several species belong to the Cryptosporidium and Giardia genus, the main parasitic protozoa occurring in water, but only some of them are infectious to humans. We investigated the occurrence of Cryptosporidium and Giardia and identified their species in the water samples collected from natural water bodies in north-western Poland. A total of 600 samples from water bodies used for bathing, sewage discharge, as drinking water sources and watering places for animals were screened. The samples were collected during a 3-year period in each of the four seasons and filtered using Filta-Max (IDEXX Laboratories, USA). Genomic DNA was extracted from all samples and used as a target sequence for polymerase chain reaction (PCR) and TaqMan real-time PCR, as well as for reverse line blotting (RLB) methods. PCR methods seem to be more sensitive to detect Giardia and Cryptosporidium DNA in water samples than RLB methods. All PCR products were sequenced and three were identified as C. parvum and four as G. intestinalis. The overall prevalence of C. parvum (0.5%) and G. intestinalis (0.6%) in the samples suggests that the risk of Cryptosporidium and Giardia infections in north-western Poland is minimal.

Occurrence of Cryptosporidium spp., Giardia spp. and other pathogenic intestinal parasites in the Beberibe River in the State of Pernambuco, Brazil.

Transmission of pathogenic protozoa and helminths by water is a serious public health problem. In this study, we analyzed the presence of these organisms in the Beberibe River in Pernambuco, Brazil. Parasite analysis was performed using the Hoffman, Pons, & Janer method followed by centrifugation and preparation of slides by staining with acetic acid and Lugol's solution. Protozoan oocysts were isolated by the modified Ziehl Neelsen method. Cryptosporidium spp., Giardia spp. and other parasites were found in the Beberibe River. Sanitation companies must assess pathogenic intestinal parasites in water basins providing public water and subsequently develop improved treatment systems for removal of such parasites.

Cryptosporidium in small water systems in Puerto Rico: a pilot study.

A pilot study was undertaken to investigate the occurrence of Cryptosporidium in four very small drinking water systems supplying communities in rural Puerto Rico. Water samples (40 L) were collected and oocysts were concentrated by calcium carbonate flocculation, recovered by immunomagnetic separation and detected by immunofluorescence microscopy. Cryptosporidium oocysts were identified in all four systems. This is the first report of evidence of the potential public health risk from this chlorine-resistant pathogen in Puerto Rican small water systems. Further work is warranted to fully assess the health risks that Cryptosporidium and other protozoa pose to populations served by community-managed small drinking water systems.