Is ITS-2 rDNA suitable marker for genetic characterization of Sarcoptes mites from different wild animals in different geographic areas?

Alasaad, Samer; Soglia, Dominga; Spalenza, Verónica; Maione, Sandra; Soriguer, Ramón C.; Pérez, Jesús M.; Rasero, Roberto; Degiorgis, Marie-Pierre; Nimmervoll, Helena; Zhu, Xing‐Quan; Rossi, Luca

doi:10.1016/j.vetpar.2008.10.001

Cited by 54 publications

(46 citation statements)

References 30 publications

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“…Previous molecular studies of S. scabiei in animals and humans have utilized various gene targets, such as microsatellites, ITS-2 ribosomal DNA (rDNA), mitochondrial 12S/16S rRNA, and S. scabiei myosin heavy chain genes (41)(42)(43)(44)(45)(46)(47)(48).…”

Section: Discussionmentioning

confidence: 99%

Development of Conventional and Real-Time Quantitative PCR Assays for Diagnosis and Monitoring of Scabies

et al. 2015

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c Scabies remains the most prevalent, endemic, and neglected ectoparasitic infestation globally and can cause institutional outbreaks. The sensitivity of routine microscopy for demonstration of Sarcoptes scabiei mites or eggs in skin scrapings is only about 50%. Except for three studies using conventional or two-tube nested PCR on a small number of cases, no systematic study has been performed to improve the laboratory diagnosis of this important infection. We developed a conventional and a real-time quantitative PCR (qPCR) assay based on the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene of S. scabiei. The cox1 gene is relatively well conserved, with its sequence having no high levels of similarity to the sequences of other human skin mites, pathogenic zoonotic mites, or common house dust mite species. This mitochondrial gene is also present in large quantities in arthropod cells, potentially improving the sensitivity of a PCR-based assay. In our study, both assays were specific and were more sensitive than microscopy in diagnosing scabies, with positive and negative predictive values of 100%. The S. scabiei DNA copy number in the microscopy-positive specimens was significantly higher than that in the microscopy-negative specimens (median S. scabiei DNA copy number, 3.604 versus 2.457 log 10 copies per reaction; P ‫؍‬ 0.0213). In the patient with crusted scabies, the qPCR assay performed on lesional skin swabs instead of scrapings revealed that the parasite DNA load took about 2 weeks to become negative after treatment. The utility of using lesional skin swabs as an alternative sample for diagnosis of scabies by PCR should be further evaluated. Scabies remains a significant infectious problem worldwide and is a problem not merely in developing countries but also in the developed world. An estimated 300 million cases of scabies occur globally every year, with scabies having a particular association with young children, poor hygiene, homelessness, crowdedness, and poverty in the tropical and subtropical regions (1). The prevalence of scabies in some populations, such as Australian aborigines, can be as high as 25 to 50%, and the burden of disease and morbidity are further aggravated by complications with bacterial pyoderma, including that caused by methicillin-resistant Staphylococcus aureus (2, 3). In developed countries, scabies causes significant public health issues in vulnerable individuals, such as individuals at the extremes of ages and immunocompromised hosts. For example, an estimated incidence of 233 to 470 per 100,000 person-years was reported in a national study conducted from 1994 to 2003 in England (4). In addition, outbreaks readily occur in the community in schools, hospitals (including intensive care units), and other institutions (5-10). Among immunocompromised patients, such as HIV-infected individuals, organ transplant recipients, and patients on biologics or other immunosuppressive therapies, scabies can occur as an unrecognized complication with considerable delays in diagnosis and...

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Section: Discussionmentioning

confidence: 99%

Development of Conventional and Real-Time Quantitative PCR Assays for Diagnosis and Monitoring of Scabies

et al. 2015

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“…The numbers represent percentage of bootstrap confidence levels obtained from the NJ (a) and MP (b) methods. The species could be easily identified by the NJ and MP trees geographically different species (Alasaad et al 2009). Nevertheless, they can help us study low-level phylogenetic relationships between astigmatid mites.…”

Section: Discussionmentioning

confidence: 99%

Identification of astigmatid mites using ITS2 and COI regions

2010

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Identification of astigmatid mites based on their morphological characteristics is difficult because of the similarity of their organs, especially in immature mites. The ribosomal second internal transcribed spacer (ITS2) and the mitochondrial cytochrome oxidase subunit I (COI) regions are highly conserved in the eukaryotes and are usually used as barcodes. The ITS2 and COI regions of six species of astigmatid mites (Aleuroglyphus ovatus, Blomia tropicalis, Dermatophagoides farinae, Dermatophagoides pteronyssinus, Euroglyphus maynei, Tyrophagus putrescentiae) were obtained by polymerase chain reaction and sequenced. The lengths of the ITS2 sequences varied from 316 to 488 bp, while the COI regions were 377 or 378 bp long. Considering the ITS2 genes, the intraspecific genetic distance was in the range of 0.00-0.077844, whereas the interspecific genetic distance was 0.202426-0.912959. The values were 0.000-0.029748 and 0.138403-0.279304 for intra- and interspecific genetic distances when COI genes were used. The phylogenetic trees inferred from the ITS2 and the COI regions, by using maximum parsimony and neighbor-joining methods, were identical to those based on their morphological classification. Thus, the ITS2 and COI regions can be applied as barcodes to identify different species of astigmatid mites.

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“…Even such recently encountered mammals as koalas and wombats have become infected with scabies. Morphological variation between the strains is small or absent, and ITS-2 also shows no host-related variation (Alasaad et al 2012 ). However, there is some evidence of host-related population genetic differentiation in microsatellites (Rasero et al 2010 ) as well as physiological differences among scabies mites from different hosts.…”

Section: Mites On and In Mammalsmentioning

confidence: 94%

Animals as Habitats

Walter

Proctor

2013

Mites: Ecology, Evolution &Amp; Behaviour

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To most non-biologists, a 'mite' is an almost invisible creature that lives in the carpet and gives you asthma or that burrows in your skin to produce socially unacceptable scabies. Cat owners may curse the ear mites that infest their pets and those who know that ticks are mites may mention Lyme Disease. Such medically important associations between mites and mammals are discussed in most parasitology texts, and mites associated with human diseases are discussed in our Chap. 10 ; therefore, in this chapter we cover ticks and other human-and livestock-associated mites superfi cially, concentrating instead on lesser known relationships between mites and the animals they use for room and board. These associations are not always negative; in fact, many seemingly parasitic mites have no impact on their hosts or may even be benefi cial (see section " Mutualism ", below).One of the recurring themes of this book is that mites live in the most astonishing places. This is particularly apparent among animal-associated acarines. A complete list of associations between mites and other animals would occupy an entire book but to whet the reader's appetite we have provided Table 9.1 , where we list the associations that acarologists use to shock jaded students or to start conversations at dull parties. After perusing this list many will be compelled to exclaim, 'What's a mite doing there?' or 'How did a mite get there?'. The fi rst question is a proximate one -what is the ecology of the symbiotic mite? -and the second an ultimate one -what evolutionary history and selective pressures have resulted in this association? In the fi rst section of this chapter we discuss the ecological terminology dealing with symbiosis and then outline some major hypotheses about how different symbioses may evolve. The next two sections discuss the life histories and behaviour of mites associated with invertebrates and vertebrates respectively and the fourth section surveys the diverse effects that parasitic mites have on their hosts. Finally, the last section addresses the topic of coevolution between hosts and symbionts from an acarine point of view.

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Is ITS-2 rDNA suitable marker for genetic characterization of Sarcoptes mites from different wild animals in different geographic areas?

Cited by 54 publications

References 30 publications

Development of Conventional and Real-Time Quantitative PCR Assays for Diagnosis and Monitoring of Scabies

Development of Conventional and Real-Time Quantitative PCR Assays for Diagnosis and Monitoring of Scabies

Identification of astigmatid mites using ITS2 and COI regions

Animals as Habitats

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