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Zajaczkowski P, Lee R, Fletcher-Lartey SM, Alexander K, Mahimbo A, Stark D, Ellis JT. The controversies surrounding Giardia intestinalis assemblages A and B. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2022; 1:100055. [PMID: 35284870 PMCID: PMC8906113 DOI: 10.1016/j.crpvbd.2021.100055] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 10/09/2021] [Indexed: 11/27/2022]
Abstract
Giardia intestinalis continues to be one of the most encountered parasitic diseases around the world. Although more frequently detected in developing countries, Giardia infections nonetheless pose significant public health problems in developed countries as well. Molecular characterisation of Giardia isolates from humans and animals reveals that there are two genetically different assemblages (known as assemblage A and B) that cause human infections. However, the current molecular assays used to genotype G. intestinalis isolates are quite controversial. This is in part due to a complex phenomenon where assemblages are incorrectly typed and underreported depending on which targeted locus is sequenced. In this review, we outline current knowledge based on molecular epidemiological studies and raise questions as to the reliability of current genotyping assays and a lack of a globally accepted method. Additionally, we discuss the clinical symptoms caused by G. intestinalis infection and how these symptoms vary depending on the assemblage infecting an individual. We also introduce the host-parasite factors that play a role in the subsequent clinical presentation of an infected person, and explore which assemblages are most seen globally.
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Affiliation(s)
- Patricia Zajaczkowski
- Faculty of Science, School of Life Sciences, University of Technology Sydney, Australia
| | - Rogan Lee
- Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, Westmead Hospital, Westmead, New South Wales, Australia.,Westmead Clinical School, Faculty of Medicine and Health, The University of Sydney, Westmead Hospital, Westmead, NSW, Australia
| | | | - Kate Alexander
- Public Health Unit, South Western Sydney Local Health District, Liverpool, Australia
| | - Abela Mahimbo
- Faculty of Health, School of Public Health, University of Technology Sydney, Australia
| | - Damien Stark
- Department of Microbiology, St Vincent's Hospital Sydney, Darlinghurst, New South Wales, Australia
| | - John T Ellis
- Faculty of Science, School of Life Sciences, University of Technology Sydney, Australia
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Cai W, Ryan U, Xiao L, Feng Y. Zoonotic giardiasis: an update. Parasitol Res 2021; 120:4199-4218. [PMID: 34623485 DOI: 10.1007/s00436-021-07325-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/16/2021] [Indexed: 12/15/2022]
Abstract
Giardia duodenalis is a common intestinal parasite in various hosts, with the disease giardiasis being a zoonosis. The use of molecular typing tools has improved our understanding of the distribution and zoonotic potential of G. duodenalis genotypes in different animals. The present review summarizes recent data on the distribution of G. duodenalis genotypes in humans and animals in different areas. The dominance of G. duodenalis assemblages A and B in humans and common occurrence of host-adapted assemblages in most domesticated animals suggests that zoonotic giardiasis is probably less common than believed and could be attributed mainly to contact with or contamination from just a few species of animals such as nonhuman primates, equines, rabbits, guinea pigs, chinchillas, and beavers. Future studies should be directed to advanced genetic characterization of isolates from well-designed epidemiological investigations, especially comparative analyses of isolates from humans and animals living in the same household or community. This will likely lead to better understanding of zoonotic transmission of G. duodenalis in different environmental and socioeconomic settings.
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Affiliation(s)
- Weilong Cai
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Una Ryan
- Vector- and Water-Borne Pathogen Research Group, Harry Butler Institute, Murdoch University, Murdoch, WA, 6150, Australia
| | - Lihua Xiao
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China. .,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China.
| | - Yaoyu Feng
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China. .,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China.
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Khine NO, Chimnoi W, Kamyingkird K, Kengradomkij C, Saetiew N, Simking P, Saengow S, Jittapalapong S, Inpankaew T. Molecular detection of Giardia duodenalis and Cryptosporidium spp. from stray dogs residing in monasteries in Bangkok, Thailand. Parasitol Int 2021; 83:102337. [PMID: 33771679 DOI: 10.1016/j.parint.2021.102337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 11/28/2022]
Abstract
Both Cryptosporidium spp. and Giardia duodenalis are enteric protozoan parasites that infect a wide variety of domestic animals as well as humans worldwide, causing diarrheal diseases. Giardia duodenalis assemblages C and D are specific to canine hosts and zoonotic assemblages A and B are also found in dogs as a reservoir host. In dogs, Cryptosporidium canis is the host-specific species while humans are infected by C. hominis and C. parvum and at least another 16 zoonotic Cryptosporidium species have been reported causing human infections, with C. meleagridis, C. viatorum, and C. ubiquitum being the most frequent. The objective of this study was to determine the prevalence of Cryptosporidium spp. and G. duodenalis from stray dogs in areas of Bangkok and to identify the species and assemblages. Fecal samples (540) were collected from dogs residing in 95 monasteries in 48 districts in the Bangkok metropolitan area. Nested Polymerase Chain Reaction (PCR) was performed using the ssu-rRNA gene for both parasites. In total, 3.0% (16/540) samples were positive for G. duodenalis, with most being G. duodenalis assemblage D (7/16) followed by assemblage C (7/16) and zoonotic assemblage A (2/16). The prevalence of Cryptosporidium spp. was 0.7% (4/540) based on the PCR results and all were the dog genotype C. canis. These results indicated that dogs residing in Bangkok monasteries poses a limited role as source of human giardiosis and cryptosporidiosis.
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Affiliation(s)
- Nwai Oo Khine
- Bio-Veterinary Science Program, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
| | - Wissanuwat Chimnoi
- Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
| | - Ketsarin Kamyingkird
- Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
| | - Chanya Kengradomkij
- Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
| | - Nantiya Saetiew
- Department of Animal Science, Faculty of Science and Technology, Muban Chombueng Rajabhat University, Ratchaburi 70120, Thailand
| | - Patcharathorn Simking
- Division of Animal Health Science, Faculty of Agricultural Technology, Rajamangala University of Technology Thanyaburi, Pathumthani 12130, Thailand
| | - Sinsamuth Saengow
- Division of Animal Health Science, Faculty of Agricultural Technology, Rajamangala University of Technology Thanyaburi, Pathumthani 12130, Thailand
| | | | - Tawin Inpankaew
- Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand.
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Lee H, Jung B, Lim JS, Seo MG, Lee SH, Choi KH, Hwang MH, Kim TH, Kwon OD, Kwak D. Multilocus genotyping of Giardia duodenalis from pigs in Korea. Parasitol Int 2020; 78:102154. [PMID: 32531468 DOI: 10.1016/j.parint.2020.102154] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 05/30/2020] [Accepted: 06/02/2020] [Indexed: 01/21/2023]
Abstract
Giardia duodenalis (syn. G. intestinalis, G. lamblia) is an important zoonotic parasite infecting livestock (including pigs) through ingesting cysts in contaminated food or water. This parasite has been classified into eight different genetic assemblages, A to H. Here, we examined the individual-level prevalence of G. duodenalis in domestic pig farms and confirmed host specificity by genotype comparisons. Samples were collected from southern and central Korea, between May 2017 and January 2019. DNA directly extracted from 745 pig fecal specimens were tested by PCR for G. duodenalis small subunit ribosomal RNA (ssu rRNA), glutamate dehydrogenase (gdh), and β-giardin gene sequences. Based on ssu rRNA PCR, 110 (14.8%) were positive for G. duodenalis. Infection risk was the highest in the fattener group (31/139, 22.3%) and during the autumn season (52/245, 21.2%: p < .001). No statistically significant differences in risk for infection were observed between fecal types (normal versus diarrheal). Fifty ssu rRNA samples, three gdh samples, and five β-giardin samples were successfully sequenced and genotyped. Ssu rRNA assemblage sequence analysis identified E (40.0%, 20/50), D (34.0%, 17/50), C (24.0%, 12/50), and A (2.0%, 1/50). The gdh locus identified three samples as assemblage E, and the β-giardin locus identified four samples as assemblage E and one as assemblage C. Assemblage A sequences obtained (ssu rRNA; MK430919) had 100% identity with Giardia sequences isolated from a Korean individual (AJ293301), indicating the potential of zoonotic transmission. Continuous management and monitoring for prevention of transmission and protection of animal and human health are essential.
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Affiliation(s)
- Haeseung Lee
- College of Veterinary Medicine, Kyungpook National University, Daegu 41566, Republic of Korea
| | - ByeongYeal Jung
- Animal and Plant Quarantine Agency, Gimcheon 39660, Republic of Korea
| | - Jun-Sik Lim
- College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Min-Goo Seo
- Animal and Plant Quarantine Agency, Gimcheon 39660, Republic of Korea
| | - Seung-Hun Lee
- College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea
| | - Kwang-Ho Choi
- Animal and Plant Quarantine Agency, Gimcheon 39660, Republic of Korea
| | - Mi-Hye Hwang
- Animal and Plant Quarantine Agency, Gimcheon 39660, Republic of Korea
| | - Tae-Hwan Kim
- College of Veterinary Medicine, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Oh-Deog Kwon
- College of Veterinary Medicine, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Dongmi Kwak
- College of Veterinary Medicine, Kyungpook National University, Daegu 41566, Republic of Korea; Cardiovascular Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea.
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SEPAHVAND A, HOSSEINI-SAFA A, YOUSOFI HA, TAJEDINI MH, PAHLAVAN GHAREHBABAH R, PESTEHCHIAN N. Genotype Characteristics of Giardia duodenalis in Patients Using High Resolution Melting Analysis Technique in Khorramabad, Iran. IRANIAN JOURNAL OF PARASITOLOGY 2020; 15:204-213. [PMID: 32595710 PMCID: PMC7311821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
BACKGROUND We aimed at genotyping and evaluating the predominance of G. duodenalis assemblages isolated from patients referred to medical laboratories in Khorramabad, Iran from Nov 2015 to Sep 2016. Hence, the development of a cost-effective HRM approach to determine genotypes of G. duodenalis based on the triosephosphate isomerase (tpi) gene was examined and the genotyping results with and without diarrhea was compared. METHODS Seventy G. duodenalis positive fecal samples were collected. A microscopic confirmation for the presence of Giardia spp. was performed, cysts of 70 Giardia spp. positive specimens were concentrated using sucrose flotation technique and sucrose solution PCR amplification was performed on 69 of 70 (98.5%) samples, and High Resolution Melting (HRM) analysis was performed using a software. RESULTS The results showed two distinct genotypes (assemblages A and B) of G. duodenalis but infections with mixture of both assemblages were not detected. The genotypes of G. duodenalis showed that the sub assemblage AI, BIII and BIV were present in a proportion of 68.1%, 20.3% and 11.6% respectively in samples. Assemblage AI was significantly (P<0.05) more frequently found in patients with diarrhea. CONCLUSION The sub-assemblage AI, BIII, and BIV are more zoonotic potential. According to the comparison of the results of this study with the results of previous studies in this area and around of it, as well as the way people live and keep pets. This pattern established in Khorramabad city. HRM can be an ideal technique to detect and genotyping of G. duodenalis in clinical samples.
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Affiliation(s)
- Akram SEPAHVAND
- Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran,Department of Medical Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ahmad HOSSEINI-SAFA
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Ali YOUSOFI
- Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran,Department of Medical Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | - Reza PAHLAVAN GHAREHBABAH
- Department of Medical Biotechnology, Faculty of Advance Medical Science, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nader PESTEHCHIAN
- Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran,Department of Medical Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran,Correspondence
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Kim HY, Lee H, Lee SH, Seo MG, Yi S, Kim JW, Kim CH, Lee YR, So B, Kwon OD, Kwak D. Multilocus genotyping and risk factor analysis of Giardia duodenalis in dogs in Korea. Acta Trop 2019; 199:105113. [PMID: 31356789 DOI: 10.1016/j.actatropica.2019.105113] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/12/2019] [Accepted: 07/25/2019] [Indexed: 11/26/2022]
Abstract
Giardia duodenalis (syn. G. intestinalis, G. lamblia), a protozoan parasite that infects most mammals (including humans), has recently been classified into eight different groups/assemblages (A to H) based on host range and genetic characteristics. Assemblages A and B have been reported in humans and in many other animals, including dogs. This study analyzed Giardia infections, implementing multilocus genotyping, including the 18S rRNA, gdh, and β-giardin genes, in sheltered, companion, and special-purpose dogs throughout Korea. Of 640 dog stool samples, 99 (15.5%) were G. duodenalis-positive; this prevalence was similar to that previously reported in Korean calves. In addition, the prevalence was significantly higher in the southern region, and lower in non-sheltered dogs, older dogs, and in the autumn season. Phylogenetic analysis revealed that all G. duodenalis-positive samples belonged to assemblages C and D. Although no G. duodenalis assemblages A and B (mainly found in humans) were identified in this study, assemblage C was detected in the main types of dogs in contact with humans. Assemblage C, thought to be dog-specific, was recently identified in humans. As Giardia (including zoonotic assemblages) is distributed throughout Korea, dog living environments and the potential for dog-human transmission should be monitored.
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Ryan U, Zahedi A. Molecular epidemiology of giardiasis from a veterinary perspective. ADVANCES IN PARASITOLOGY 2019; 106:209-254. [PMID: 31630759 DOI: 10.1016/bs.apar.2019.07.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A total of eight Giardia species are accepted. These include: Giardia duodenalis (syn. Giardia intestinalis and Giardia lamblia), which infects humans and animals, Giardia agilis, Giardia ardeae, Giardia psittaci, Giardia muris, Giardia microti, Giardia peramelis and G. cricetidarum, which infect non-human hosts including amphibians, birds, rodents and marsupials. Giardia duodenalis is a species complex consisting of eight assemblages (A-H), with assemblages A and B the dominant assemblages in humans. Molecular studies to date on the zoonotic potential of Giardia in animals are problematic and are hampered by lack of concordance between loci. Livestock (cattle, sheep, goats and pigs) are predominantly infected with G. duodenalis assemblage E, which has recently been shown to be zoonotic, followed by assemblage A. In cats and dogs, assemblages A, B, C, D and F are commonly reported but relatively few studies have conducted molecular typing of humans and their pets and the results are contradictory with some studies support zoonotic transmission but the majority of studies suggesting separate transmission cycles. Giardia also infects a broad range of wildlife hosts and although much less well studied, host-adapted species as well as G. duodenalis assemblages (A-H) have been identified. Fish and other aquatic wildlife represent a source of infection for humans with Giardia via water contamination and/or consumption of undercooked fish and interestingly, assemblage B and A predominated in the two molecular studies conducted to date. Our current knowledge of the transmission dynamics of Giardia is still poor and the development of more discriminatory typing tools such as whole genome sequencing (WGS) of Giardia isolates is therefore essential.
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Affiliation(s)
- Una Ryan
- College of Science, Health, Education and Engineering, Murdoch University, Perth, WA, Australia.
| | - Alireza Zahedi
- College of Science, Health, Education and Engineering, Murdoch University, Perth, WA, Australia
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Giardia duodenalis in the UK: current knowledge of risk factors and public health implications. Parasitology 2018; 146:413-424. [PMID: 30318029 DOI: 10.1017/s0031182018001683] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Giardia duodenalis is a ubiquitous flagellated protozoan parasite known to cause giardiasis throughout the world. Potential transmission vehicles for this zoonotic parasite are both water and food sources. As such consumption of water contaminated by feces, or food sources washed in contaminated water containing parasite cysts, may result in outbreaks. This creates local public health risks which can potentially cause widespread infection and long-term post-infection sequelae. This paper provides an up-to-date overview of G. duodenalis assemblages, sub-assemblages, hosts and locations identified. It also summarizes knowledge of potential infection/transmission routes covering water, food, person-to-person infection and zoonotic transmission from livestock and companion animals. Public health implications focused within the UK, based on epidemiological data, are discussed and recommendations for essential Giardia developments are highlighted.
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Fantinatti M, Caseca AC, Bello AR, Fernandes O, Da-Cruz AM. The presence of Giardia lamblia assemblage A in dogs suggests an anthropozoonotic cycle of the parasite in Rio de Janeiro, Brazil. INFECTION GENETICS AND EVOLUTION 2018; 65:265-269. [PMID: 30044958 DOI: 10.1016/j.meegid.2018.07.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 10/28/2022]
Abstract
BACKGROUND Giardia lamblia is a zoonotic protozoan that is classified into 8 genotypes and is distributed worldwide. Assemblages A and B were found to infect dogs and humans, whereas assemblages C and D are dog host-specific. Our objective was to investigate the G. lamblia genotypes circulating in a canine population in Rio de Janeiro, RJ. RESULTS Sixty stool samples positive for G. lamblia from street dogs were characterized. Fragments of the conserved genes encoding beta-giardin (β-gia) and glutamate dehydrogenase (gdh) were used as targets. The sequences from beta-giardin and glutamate dehydrogenase genes obtained from all 60 dog samples were 100% similar to G. lamblia genotype A. CONCLUSION The detection of genotype A suggests that G. lamblia transmission in Rio de Janeiro has a predominantly anthropozoonotic cycle.
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Affiliation(s)
- Maria Fantinatti
- Laboratório Interdisciplinar de Pesquisas Médicas, Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro/RJ, CEP 21040-360, Brazil.
| | - Aline Cardoso Caseca
- Instituto de Saúde de Nova Friburgo, Universidade Federal Fluminense, Nova Friburgo/RJ, CEP 28625-650, Brazil.
| | - Alexandre Ribeiro Bello
- Disciplina de Parasitologia-DMIP, Faculdade de Ciências Médicas-UERJ, Rio de Janeiro/RJ, CEP 20551-030, Brazil.
| | - Octavio Fernandes
- Laboratório Interdisciplinar de Pesquisas Médicas, Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro/RJ, CEP 21040-360, Brazil.
| | - Alda Maria Da-Cruz
- Laboratório Interdisciplinar de Pesquisas Médicas, Instituto Oswaldo Cruz - FIOCRUZ, Rio de Janeiro/RJ, CEP 21040-360, Brazil; Disciplina de Parasitologia-DMIP, Faculdade de Ciências Médicas-UERJ, Rio de Janeiro/RJ, CEP 20551-030, Brazil.
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Adell-Aledón M, Köster PC, de Lucio A, Puente P, Hernández-de-Mingo M, Sánchez-Thevenet P, Dea-Ayuela MA, Carmena D. Occurrence and molecular epidemiology of Giardia duodenalis infection in dog populations in eastern Spain. BMC Vet Res 2018; 14:26. [PMID: 29357850 PMCID: PMC5778629 DOI: 10.1186/s12917-018-1353-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 01/16/2018] [Indexed: 01/23/2023] Open
Abstract
Background Giardia duodenalis is one of the most common enteric parasites in domestic animals including dogs. Young animals are more prone to the infection, with clinical manifestations ranging from asymptomatic to acute or chronic diarrhoea. Dogs are primarily infected by canine-specific (C-D) assemblages of G. duodenalis. However, zoonotic assemblages A and B have been increasingly documented in canine isolates, raising the question of whether and to which extent dogs can act as natural reservoirs of human giardiosis. Methods In this cross-sectional epidemiological survey we assessed the molecular diversity of G. duodenalis in dogs in the province of Castellón, Eastern Spain. A total of 348 individual faecal samples from sheltered (n = 218), breeding (n = 24), hunting (n = 68), shepherd (n = 24), and pet (n = 14) dogs were collected between 2014 and 2016. Detection of G. duodenalis cysts in faecal material was carried out by direct fluorescence microscopy as a screening test, whereas a qPCR targeting the small subunit ribosomal RNA gene of the parasite was subsequently used as a confirmatory method. Results Giardia duodenalis was detected in 36.5% (95% CI: 31.6–41.7%) of dogs. No significant differences in prevalence rates could be demonstrated among dogs according to their sex and geographical origin, but breeding (45.8%; 95% CI: 27.9–64.9%) and sheltered (40.4%; 95% CI: 34.1–47.0%) dogs harboured significantly higher proportions of G. duodenalis. Multi-locus sequence-based genotyping of the glutamate dehydrogenase and β-giardin genes of G. duodenalis allowed the characterization of 35 canine isolates that were unambiguously assigned to assemblages A (14.3%), B (22.9%), C (5.7%), and D (37.1%). A number of inter-assemblage mixed infections including A + B (11.4%), A + D (2.9%), and A + B + D (5.7%) were also identified. Conclusions Data presented here are strongly indicative of high infection pressures in kennelled animals. Zoonotic sub-assemblages AII, BIII, and BIV were responsible for a considerable proportion of the G. duodenalis infections detected, but very few of the genotypes identified have been previously documented in Spanish human populations. Although possible, zoonotic transmission between dogs and humans seems an infrequent event in this Spanish region. Electronic supplementary material The online version of this article (10.1186/s12917-018-1353-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Manuel Adell-Aledón
- CEU Cardenal Herrera University, C/ Grecia, 31, 12006, Castellón de la Plana, Castellón, Spain
| | - Pamela C Köster
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220, Majadahonda, Madrid, Spain
| | - Aida de Lucio
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220, Majadahonda, Madrid, Spain
| | - Paula Puente
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220, Majadahonda, Madrid, Spain
| | - Marta Hernández-de-Mingo
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220, Majadahonda, Madrid, Spain
| | - Paula Sánchez-Thevenet
- CEU Cardenal Herrera University, C/ Grecia, 31, 12006, Castellón de la Plana, Castellón, Spain
| | | | - David Carmena
- CEU Cardenal Herrera University, C/ Grecia, 31, 12006, Castellón de la Plana, Castellón, Spain. .,Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220, Majadahonda, Madrid, Spain.
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Genetic variability and transcontinental sharing of Giardia duodenalis infrapopulations determined by glutamate dehydrogenase gene. Acta Trop 2018; 177:146-156. [PMID: 29030042 DOI: 10.1016/j.actatropica.2017.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 09/18/2017] [Accepted: 10/02/2017] [Indexed: 12/07/2022]
Abstract
Microevolutionary data of Giardia duodenalis sub-assemblages is a prerequisite for determining the invasion zoonotic patterns of the parasite. To infer transmission patterns that could not be differentiated by the phenotypic features, a population genetic investigation is crucial for the elucidation of the genetic structure of G. duodenalis among the continents. Forty G. duodenalis positive fecal samples were collected from different foci of Northwest Iran. The specimens were subjected to Trichrome staining and sucrose gradient flotation. DNA samples were extracted, amplified, and sequenced by targeting glutamate dehydrogenase (gdh) gene. The global gdh sequences of sub-assemblages AII and BIV retrieved from NCBI GenBank were analyzed to estimate diversity indices, neutrality indices, and gene migration tests. Sequencing analyses indicated various levels of genetic variability of sub-assemblages AII and BIV among the five continents. Sub-assemblage BIV had greater genetic variability (haplotype diversity: 0.975; nucleotide diversity: 0.04246) than sub-assemblage AII. The statistical Fst value demonstrated that the genetic structure of sub-assemblages AII and BIV are moderately differentiated between European-American populations (Fst: 0.05352-0.15182), whereas a significant differentiation was not seen among other geographical population pairs. We conclude that a high gene flow of G. duodenalis sub-assemblages AII and BIV is unequivocally sharing among the continents. The current findings strengthen our knowledge to assess the evolutionary patterns of G. duodenalis in endemic foci of the world and it will become the basis of public health policy to control human giardiasis.
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Olmo L, Dye M, Reichel M, Young J, Nampanya S, Khounsy S, Thomson P, Windsor P, Bush R. Investigation of infectious reproductive pathogens of large ruminants: Are neosporosis, brucellosis, leptospirosis and BVDV of relevance in Lao PDR? Acta Trop 2018; 177:118-126. [PMID: 29024616 DOI: 10.1016/j.actatropica.2017.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 09/25/2017] [Accepted: 10/07/2017] [Indexed: 10/18/2022]
Abstract
N. caninum, bovine viral diarrhoea virus, Brucella abortus and Leptospira interrogans serovar Hardjo are globally significant reproductive pathogens that cause abortion and reproductive loss in large ruminants. Prevalence information is lacking in Lao People's Democratic Republic (Laos) despite the poor reproductive performance of cattle and buffalo. Serological examination of frozen cattle (n=90) and buffalo (n=61) sera by commercially available enzyme-linked immunosorbent assays provided the first reported screening of some of these pathogens in Laos. Seroprevalence differed amongst these large ruminant species, with N. caninum, BVDV and L. interrogans serovar Hardjo antibodies found in 68.9% (95% CI±11.6), 4.9% (95% CI±5.4) and 3.3% (95% CI±4.5) of buffalo sera, respectively, and in 7.8% (95% CI±5.5), 10.0% (95% CI±6.2) and 22.2% (95% CI±8.6) of cattle sera, respectively. Buffalo sera had a significantly higher seroprevalence of N. caninum compared to cattle (p<0.001) and cattle sera had a significantly higher seroprevalence of L. interrogans serovar Hardjo compared to buffalo (p=0.003). Variability was also observed across provinces for N. caninum in buffalo (p=0.007) and for L. interrogans serovar Hardjo in cattle (p=0.071), suggesting provincial risk factors conducive to pathogen transmission. BVDV and N. caninum seropositivity were negatively associated in buffalo (p=0.018) and cattle (p=0.003). In buffalo, L. interrogans serovar Hardjo and BVDV seropositivity were associated (p=0.035, p=0.039). The identification of antibodies against three major abortifacient pathogens in Laos prompts further research to determine if infection is associated with low reproductive efficiency and the risk factors for infection. This is needed for the development of evidence based prevention strategies for improved large ruminant reproductive management among smallholders in Laos.
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Simonato G, Frangipane di Regalbono A, Cassini R, Traversa D, Tessarin C, Di Cesare A, Pietrobelli M. Molecular detection of Giardia duodenalis and Cryptosporidium spp. in canine faecal samples contaminating public areas in Northern Italy. Parasitol Res 2017; 116:3411-3418. [DOI: 10.1007/s00436-017-5671-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 10/31/2017] [Indexed: 10/18/2022]
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Prevalence of Selected Zoonotic and Vector-Borne Agents in Dogs and Cats on the Pine Ridge Reservation. Vet Sci 2017; 4:vetsci4030043. [PMID: 29056701 PMCID: PMC5644658 DOI: 10.3390/vetsci4030043] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 08/26/2017] [Accepted: 08/30/2017] [Indexed: 11/17/2022] Open
Abstract
The prevalence of intestinal parasites and vector-borne agents of dogs and cats in the Pine Ridge Reservation, South Dakota were determined. Fecal samples (84 dogs, 9 cats) were examined by centrifugal floatation and by immunofluorescence assay (FA) for Giardia and Cryptosporidium. PCR was performed on Giardia [beta-giardin (bg), triose phosphate isomerase (tpi), glutamate dehydrogenase genes (gdh)] and Cryptosporidium [heat shock protein-70 gene (hsp)] FA positive samples. Cat sera (n = 32) were tested for antibodies against Bartonella spp., Toxoplasma gondii, and FIV, and antigens of FeLV and Dirofilaria immitis. Dog sera (n = 82) were tested for antibodies against T. gondii, Borrelia burgdorferi, Ehrlichia canis, and Anaplasma phagocytophilum and D. immitis antigen. Blood samples (92 dogs, 39 cats) were assessed by PCR for amplification of DNA of Bartonella spp., Ehrlichia spp., Anaplasma spp., haemoplasmas, and Babesia spp. (dogs only). The most significant results were Giardia spp. (32% by FA), Taenia spp. (17.8%) and Cryptosporidium spp. (7.1%). The Giardia isolates typed as the dog-specific assemblages C or D and four Cryptosporidium isolates typed as C. canis. Antibodies against T. gondii were detected in 15% of the dogs. Antibodies against Bartonella spp. and against T. gondii were detected in 37.5% and 6% of the cats respectively. FeLV antigen was detected in 10% of the cats.
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Gil H, Cano L, de Lucio A, Bailo B, de Mingo MH, Cardona GA, Fernández-Basterra JA, Aramburu-Aguirre J, López-Molina N, Carmena D. Detection and molecular diversity of Giardia duodenalis and Cryptosporidium spp. in sheltered dogs and cats in Northern Spain. INFECTION GENETICS AND EVOLUTION 2017; 50:62-69. [DOI: 10.1016/j.meegid.2017.02.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 02/14/2017] [Accepted: 02/15/2017] [Indexed: 12/11/2022]
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de Lucio A, Bailo B, Aguilera M, Cardona GA, Fernández-Crespo JC, Carmena D. No molecular epidemiological evidence supporting household transmission of zoonotic Giardia duodenalis and Cryptosporidium spp. from pet dogs and cats in the province of Álava, Northern Spain. Acta Trop 2017; 170:48-56. [PMID: 28235458 DOI: 10.1016/j.actatropica.2017.02.024] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 02/09/2017] [Accepted: 02/16/2017] [Indexed: 11/19/2022]
Abstract
The role of pet dogs and cats as suitable source of human infections by the diarrheagenic protozoan parasites Giardia duodenalis and Cryptosporidium spp. has been a topic of intense debate for long time and still remains a largely unsolved problem. In this cross-sectional molecular epidemiological survey we attempted to investigate whether zoonotic (or zooanthroponotic) disease transmission was occurring among humans and domestic dogs and cats sharing the same spatial and temporal setting in both rural and urban areas of the province of Álava, Northern Spain. A total of 268 (including 179 human, 55 canine, and 34 feline) individual faecal specimens were obtained from 63 family households during February-March and November-December 2014. Detection of G. duodenalis cysts and Cryptosporidium spp. oocysts was achieved by direct fluorescence microscopy (DFAT) and PCR-based methods targeting the small subunit (SSU) ribosomal RNA gene of the parasites. Giardia-positive isolates were subsequently sub-genotyped at the glutamate dehydrogenase (GDH) and β-giardin (BG) genes. Overall, G. duodenalis infections were identified in 3.4% (6/179) of humans, 29% (16/55) of dogs, and 5.9% (2/34) of cats, respectively. Cryptosporidium spp. infections were detected in 1.1% (2/179) of humans, 5.5% (3/55) of dogs, and 8.8% (3/34) of cats, respectively. Simultaneous infections in human and canine/feline hosts by G. duodenalis or Cryptosporidium spp. were only demonstrated in a single household in which a cat and its owner tested positive for Cryptosporidium by DFAT, but this result could not be confirmed by SSU-PCR. Infections were homogeneously distributed among the studied human or animal populations irrespectively of their sex, age group, or geographical region of origin. Inadequate washing of raw vegetables and fruits was the only risk factor significantly associated to a higher likelihood of having human giardiosis/cryptosporidiosis. Molecular characterization of G. duodenalis isolates revealed the presence of sub-assemblage BIV in a single human isolate. All dog (n=3) and cat (n=2) isolates successfully genotyped were assigned to canine- and feline-specific assemblages C and F, respectively. No mixed assemblage or sub-assemblage infections could be demonstrated. Regarding Cryptosporidium, C. canis was found infecting dogs (n=2), and C. felis a single cat. Attempts to amplify and characterize Cryptosporidium human isolates failed repeatedly. Our results suggest that pet dogs and cats do not seem to play a significant role as suitable reservoirs of human giardiosis or cryptosporidiosis in the province of Álava. We conclude, therefore, that zoonotic transmission of giardiosis or cryptosporidiosis among pet dogs and cats and their owners in this geographical region is very likely a rare event.
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Affiliation(s)
- Aida de Lucio
- Parasitology Service, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain
| | - Begoña Bailo
- Parasitology Service, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain
| | - María Aguilera
- Parasitology Service, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain
| | - Guillermo A Cardona
- Livestock Laboratory, Regional Government of Álava, Ctra. de Azua 4, 01520 Vitoria-Gasteiz, Spain
| | - Juan C Fernández-Crespo
- Sub-Direction of Public Health of Álava, Department of Health, Basque Government, Avda. Santiago 11, 01002 Vitoria-Gasteiz, Spain
| | - David Carmena
- Parasitology Service, National Centre for Microbiology, Health Institute Carlos III, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain.
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Zhang XX, Zheng WB, Ma JG, Yao QX, Zou Y, Bubu CJ, Zhao Q, Zhu XQ. Occurrence and multilocus genotyping of Giardia intestinalis assemblage C and D in farmed raccoon dogs, Nyctereutes procyonoides, in China. Parasit Vectors 2016; 9:471. [PMID: 27576343 PMCID: PMC5004317 DOI: 10.1186/s13071-016-1771-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 08/23/2016] [Indexed: 11/10/2022] Open
Abstract
Background Giardia intestinalis, the only causative agent of human giardiasis, can infect a wide range of animals. As no information concerning the prevalence and genotyping of G. intestinalis in raccoon dogs in China is available, examination of 305 faecal samples from raccoon dogs in Jilin Province (n = 110), Heilongjiang Province (n = 40), Liaoning Province (n = 72), Hebei Province (n = 54) and Shandong Province (n = 29) was conducted to estimate the prevalence of G. intestinalis in raccoon dogs in northern China and identify their genotypes using a genetic approach. Findings Of 305 faecal samples from farmed raccoon dogs, 22 (7.21 %) were detected G. intestinalis-positive by nested PCR amplification of the triosephosphate isomerase (tpi) gene. The prevalence of G. intestinalis was strongly related to the region and season of sampling. All 22 samples were analysed at the tpi, the glutamate dehydrogenase (gdh) and the beta giardin (bg) gene loci, showing 13, 3, 2 subtypes, respectively. The results also demonstrated that two raccoon dogs harboured mixed infections of assemblage C and assemblage D (or mixed C/D), whereas only assemblage C was detected in the remaining 20 samples. Moreover, five new multilocus genotypes, named as MLGs C1-C5, were observed in the assemblage C in the present study. Conclusions This is the first report of G. intestinalis infection in raccoon dogs in China. DNA sequence analysis of the tpi, gdh and bg gene indicated that 13, 3, 2 subtypes were found at these loci, respectively. Furthermore, this is also the first report of five new multilocus genotypes (MLGs C1-C5) in farmed raccoon dogs, which provides baseline data for further studies of the distribution of G. duodenalis in different hosts.
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Affiliation(s)
- Xiao-Xuan Zhang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.,College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, People's Republic of China
| | - Wen-Bin Zheng
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.,College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, People's Republic of China
| | - Jian-Gang Ma
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.,College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, People's Republic of China
| | - Qiu-Xia Yao
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.,Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu Province, 225009, People's Republic of China
| | - Yang Zou
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.,College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, People's Republic of China
| | - Cai-Jia Bubu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.,College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, People's Republic of China
| | - Quan Zhao
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, People's Republic of China
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China. .,College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, People's Republic of China. .,Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu Province, 225009, People's Republic of China.
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Comparison and evaluation of four methods for extracting DNA from Giardia duodenalis cysts for PCR targeting the tpi gene. J Parasit Dis 2016; 41:263-267. [PMID: 28316423 DOI: 10.1007/s12639-016-0790-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 05/25/2016] [Indexed: 10/21/2022] Open
Abstract
Giardia duodenalis is an intestinal flagellated protozoan and the common cause of gastrointestinal diseases in human. This parasite can be seen in two different forms in its life cycle including as cyst and trophozoite. Due to presence of resistant cyst wall, DNA extraction inhibitors along with artifact in stool specimens, this study was performed aiming to evaluate four methods for DNA extraction from G. duodenalis cysts. Seventy G. duodenalis positive stool specimens that were confirmed by light microscope were included in this study. All stool samples were concentrated using four layered discontinuous sucrose flotation technique (0.5, 0.75, 1, and 1.5 M) and single-layered sucrose solution (0.85 M). The isolated cysts were then subjected to DNA extraction by four methods. To remove the artifacts, the extracted DNA were evaluated by PCR. The results of the present study showed the high level of optical density (OD) in the method I (P < 0.01) with the following steps; Giardia cysts plus crushed cover glass were vortexed. Then, the samples were boiled and then followed by freeze-thaw cycles, yet this method yielded the lowest concentration. Furthermore, the highest concentration were observed in the method II (P <0.01) with the following steps; Giardia cysts plus crushed cover glass and TAE buffer were mixed and then shaken, followed by boiling. Based on the results of the present study, using crushed cover glass, boiling and freeze-thaw cycles can be effective in destruction of G. duodenalis cyst wall and have enough efficiency for extracting DNA from G. duodenalis cysts.
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Thompson R, Ash A. Molecular epidemiology of Giardia and Cryptosporidium infections. INFECTION GENETICS AND EVOLUTION 2016; 40:315-323. [DOI: 10.1016/j.meegid.2015.09.028] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Revised: 09/23/2015] [Accepted: 09/24/2015] [Indexed: 11/28/2022]
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Heyworth MF. Giardia duodenalis genetic assemblages and hosts. ACTA ACUST UNITED AC 2016; 23:13. [PMID: 26984116 PMCID: PMC4794627 DOI: 10.1051/parasite/2016013] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/06/2016] [Indexed: 01/12/2023]
Abstract
Techniques for sub-classifying morphologically identical Giardia duodenalis trophozoites have included comparisons of the electrophoretic mobility of enzymes and of chromosomes, and sequencing of genes encoding β-giardin, triose phosphate isomerase, the small subunit of ribosomal RNA and glutamate dehydrogenase. To date, G. duodenalis organisms have been sub-classified into eight genetic assemblages (designated A–H). Genotyping of G. duodenalis organisms isolated from various hosts has shown that assemblages A and B infect the largest range of host species, and appear to be the main (or possibly only) G. duodenalis assemblages that undeniably infect human subjects. In at least some cases of assemblage A or B infection in wild mammals, there is suggestive evidence that the infection had resulted from environmental contamination by G. duodenalis cysts of human origin.
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Affiliation(s)
- Martin F Heyworth
- Research Service (151), Corporal Michael J. Crescenz Veterans Affairs (VA) Medical Center, University and Woodland Avenues, Philadelphia, PA 19104, USA - Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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