Distribution of <i>Cryptosporidium</i> Species and Subtypes in Water Samples in Portugal: A Preliminary Study

Alves, Margarida; Ribeiro, Ana María; Neto, Célia; Ferreira, Elisabete; Benoliel, Maria João; Antúnes, Francisco; Matos, Olga

doi:10.1111/j.1550-7408.2006.00162.x

Cited by 16 publications

(13 citation statements)

References 10 publications

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“…Thus, two different sequences were seen within the subtype IIdA17G1, identified in over half of the lambs and goat kids. Two-thirds of these isolates, named subtype IIdA17G1a, demonstrated 100% sequence identity to the Portuguese human isolate CT1, also reported in four cattle and one water sample in the same country (4,5). By contrast, the subtype designated IIdA17G1b differed from the Portuguese isolates by a single base transition and is reported here for the first time.…”

Section: Discussionmentioning

confidence: 76%

Cryptosporidium Genotypes and Subtypes in Lambs and Goat Kids in Spain

Quílez

Torres

Chalmers

et al. 2008

Appl Environ Microbiol

136

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To provide information on the transmission dynamics of cryptosporidial infections in domestic small ruminants and the potential role of sheep and goats as a source for human cryptosporidiosis, Cryptosporidiumpositive isolates from 137 diarrheic lambs and 17 goat kids younger than 21 days of age were examined by using genotyping and subtyping techniques. Fecal specimens were collected between 2004 and 2006 from 71 sheep and 7 goat farms distributed throughout Aragón (northeastern Spain). Cryptosporidium parvum was the only species identified by restriction analyses of PCR products from small-subunit rRNA genes from all 154 microscopy-positive isolates and the sequencing of a subset of 50 isolates. Sequence analyses of the glycoprotein (GP60) gene revealed extensive genetic diversity within the C. parvum strains in a limited geographical area, in which the isolates from lambs exhibited 11 subtypes in two subtype families (IId and IIa) and those from goat kids displayed four subtypes within the family IId. Most isolates (98%) belonged to the subtype family IId, whereas only three isolates belonged to the most widely distributed family, IIa. Three of the four most prevalent subtypes (IIdA17G1a, IIdA19G1, and IIdA18G1) were previously identified in humans, and five subtypes (IIdA14G1, IIdA15G1, IIdA24G1, IIdA25G1, and IIdA26G1) were novel subtypes. All IId subtypes were identical to each other in the nonrepeat region, except for subtypes IIdA17G1b and IIdA22G1, which differed by a single nucleotide polymorphism downstream of the trinucleotide repeats. These findings suggest that lambs and goat kids are an important reservoir of the zoonotic C. parvum subtype family IId for humans.

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Section: Discussionmentioning

confidence: 76%

Cryptosporidium Genotypes and Subtypes in Lambs and Goat Kids in Spain

Quílez

Torres

Chalmers

et al. 2008

Appl Environ Microbiol

136

View full text Add to dashboard Cite

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“…To date, the major drawback to identification of C. hominis and C. parvum has been the requirement for PCR and DNA sequencing analysis of amplicons (1)(2)(3)(4)(5)31). This approach is expensive and time-consuming and available only in select laboratories.…”

Section: Discussionmentioning

confidence: 99%

“…The Luminex platform proved to be reliable and robust for this purpose and allowed rapid identification of C. hominis and C. parvum without cross-reaction with DNA from a number of distinct intestinal parasites. For this study, we chose the M15/M16 primers for amplification of the Cryptosporidium microsatellite locus ML-2 region because previous studies showed the usefulness of these primers for identification of C. hominis and C. parvum (1,4). In addition, no ML-2 sequences for Cryptosporidium species other than C. hominis and C. parvum have been deposited thus far in GenBank, and these PCR primers were very sensitive in our hands compared with others described previously for detection of Cryptosporidium sp.…”

Section: Discussionmentioning

confidence: 99%

Rapid Microsphere Assay for Identification of Cryptosporidium hominis and Cryptosporidium parvum in Stool and Environmental Samples

et al. 2007

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Cryptosporidium hominis and Cryptosporidium parvum are associated with massive disease outbreaks worldwide. Because these two species have different transmission cycles, identification of these parasites to the species level in clinical samples may provide laboratory data of crucial importance in epidemiologic investigations. To date, the most reliable way to differentiate C. hominis and C. parvum is based on DNA sequencing analysis of PCR amplicons. Although this approach is very effective for differentiation of Cryptosporidium species, it is labor-intensive and time-consuming compared with methods that do not require DNA sequencing analysis as an additional step and that have been successfully used for specific identification of a number of pathogens. In this study, we describe a novel Luminex-based assay that can differentiate C. hominis from C. parvum in a rapid and cost-effective manner. The assay was validated by testing a total of 143 DNA samples extracted from clinical specimens, environmental samples, or samples artificially spiked with Cryptosporidium oocysts. As few as 10 oocysts per 300 l of stools could be detected with this assay. The assay format includes species-specific probes linked to carboxylated Luminex microspheres that hybridize to a Cryptosporidium microsatellite-2 region (ML-2) where C. hominis and C. parvum differ by one nucleotide substitution. The assay proved to be 100% specific when samples that had been characterized by direct fluorescent antibody test (DFA) and DNA sequencing analysis were tested. In addition, the assay was more sensitive than DFA and provided species identification, which is an advantage for epidemiologic studies.

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“…There have been some suggestions (24,57) that strain variation within Cryptosporidium species is correlated with geographical origin. Also, various authors (1,5,7,51,84,87) have reported gp60 genotypes or subgenotypes that infect both humans and animals and have formulated hypotheses regarding the importance of zoonotic transmission in causing sporadic cases or outbreaks of cryptosporidiosis in humans. However, to date neither the global distribution of gp60 genotypes and subgenotypes nor the range in host specificities of these types has been assessed comprehensively.…”

Section: Vol 46 2008 Characterizing Sporadic Human Cryptosporidiosimentioning

confidence: 99%

Classification ofCryptosporidiumSpecies from Patients with Sporadic Cryptosporidiosis by Use of Sequence-Based Multilocus Analysis following Mutation Scanning

et al. 2008

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In the present study, we analyzed genetic variation in Cryptosporidium species from humans (n ‫؍‬ 62) with clinical cryptosporidiosis in South Australia. Sequence variation was assessed in regions within the small subunit of nuclear rRNA (p-SSU), the 70-kDa heat shock protein (p-hsp70), and the 60-kDa glycoprotein (p-gp60) genes by employing single-strand conformation polymorphism analysis and sequencing. Based on the analyses of p-SSU and p-hsp70, Cryptosporidium hominis (n ‫؍‬ 38) and Cryptosporidium parvum (n ‫؍‬ 24) were identified. The analysis of p-gp60 revealed eight distinct subgenotypes, classified as C. hominis IaA17R1 (n ‫؍‬ 3), IbA9G3R2 (n ‫؍‬ 14), IbA10G2R2 (n ‫؍‬ 20), and IfA12G1R1 (n ‫؍‬ 1), as well as C. parvum IIaA18G3R1 (n ‫؍‬ 15), IIaA20G3R1 (n ‫؍‬ 6), IIaA22G4R1 (n ‫؍‬ 2), and IIcA5G3R2 (n ‫؍‬ 1). Subgenotypes IaA17R1 and IIaA22G4R1 are new. Of the six other subgenotypes, IbA10G2R2, IIaA18G3R1, IIaA20G3R1, and IIcA5G3R2 were reported previously from the state of Victoria. This is the fourth record in Australia of C. parvum subgenotype IIaA18G3R1 from humans, which, to date, has been isolated only from cattle in other countries. This subgenotype might be a significant contributor to sporadic human cryptosporidiosis and may indicate a greater zoonotic contribution to the infection of humans in the area of study. Comparative analyses revealed, for the first time, the differences in the genetic makeup of Cryptosporidium populations between two relatively close, major metropolitan cities.

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Distribution of Cryptosporidium Species and Subtypes in Water Samples in Portugal: A Preliminary Study

Cited by 16 publications

References 10 publications

Cryptosporidium Genotypes and Subtypes in Lambs and Goat Kids in Spain

Cryptosporidium Genotypes and Subtypes in Lambs and Goat Kids in Spain

Rapid Microsphere Assay for Identification of Cryptosporidium hominis and Cryptosporidium parvum in Stool and Environmental Samples

Classification ofCryptosporidiumSpecies from Patients with Sporadic Cryptosporidiosis by Use of Sequence-Based Multilocus Analysis following Mutation Scanning

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