title: Genetic variability and discrimination of low doses ofToxocaraspp. from public areas soil inferred by loop-mediated isothermal amplification assay as a field-friendly molecular tool.
abstract: Aim: One of the main diagnostic problems of conventional polymerase chain reaction (PCR) is indiscrimination of low parasitic loads in soil samples. The aim of this study is to determine the genetic diversity and identification ofToxocaraspp. from public areas soil inferred by loop-mediated isothermal amplification (LAMP) assay.
  
  
  METHODS
  A total of 180 soil samples were collected from various streets and public parks of northwest Iran. The DNA of recoveredToxocaraeggs were extracted and amplified by PCR and LAMP following ZnSO4flotation technique. The amplicons of internal transcribed spacer-2 gene were sequenced to reveal the heterogeneity traits ofToxocaraspp. In addition,Toxocara canissequences of southwest Iran were directly retrieved to compare gene flow between two distinct populations.
  
  
  RESULTS
  Toxocaraspp. eggs were found in 57, 14 and 77 of soil samples using the microscopy, PCR and LAMP (detection limit 1-3 eggs/200 g soil), respectively. 7.7% of isolates were identified asT. canisby PCR method, while LAMP was able to detect 27.2%, 15.5% and 12.2% asToxocara cati,T. canisand mixed infections, respectively. The kappa coefficient between LAMP and microscopy indicated a strong agreement (0.765) but indicated a faint agreement among LAMP-PCR (0.203) and PCR-microscopy (0.308) methods. A pairwise fixation index (Fst) as a degree of gene flow was generally low (0.02156) amongToxocarapopulations of northwest and southwest Iran.
  
  
  CONCLUSIONS
  The statistically significantFst value indicates that theT. canispopulations are not genetically well differentiated between northwest and southwest Iran. This shows that here is possibly an epidemiological drift due to the transfer of alleles. The LAMP assay because of its shorter reaction time, more sensitivity, and simultaneous detection of environmental contamination to be appears as valuable field diagnosis compared to PCR. Therefore, the detection of lowToxocaraspp. loads from public area soils will help to expand epidemiological understanding of toxocariasis and establishing preventive strategies in resource-limited endemic of Iran.
authors.affiliation: Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Ozlati
authors.affiliation: Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Adel
authors.initials: A
authors.lastname: Spotin
authors.affiliation: Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Abbas
authors.initials: A
authors.lastname: Shahbazi
authors.affiliation: Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Mahami-Oskouei
authors.affiliation: Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Teimour
authors.initials: T
authors.lastname: Hazratian
authors.affiliation: Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Adibpor
authors.affiliation: Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Ahmadpour
authors.affiliation: Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Afsaneh
authors.initials: A
authors.lastname: Dolatkhah
authors.affiliation: Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Paria
authors.initials: P
authors.lastname: Khoshakhlagh
keywords: Iran; Toxocara spp; gene flow; loop-mediated isothermal amplification; polymerase chain reaction; soil