title: Multilocus genotyping of Giardia duodenalis isolates from children in Oromia Special Zone, central Ethiopia.
abstract: BACKGROUND
  Giardia duodenalis is the etiologic agent of giardiasis in humans and other mammals worldwide. The burden of disease is high among children in developing countries where sanitation is inadequate. However, the epidemiology and genetic diversity of this parasite is poorly understood in Ethiopia. This study aimed to determine the prevalence and genetic diversity of G. duodenalis in asymptomatic children in Oromia Special Zone, central Ethiopia.
  
  
  RESULTS
  A total of 286 fresh fecal specimens were collected from children and screened using microscopy and PCR. The prevalence of Giardia duodenalis was 10.8 % (31/286) and 16.8 % (48/286) as detected by microscopy and nested PCR, respectively. The infection rate by the study area, sex and age group difference was not significant (P > 0.05). Genotyping results showed that 22.9 % (11/48) of the isolates belonged to assemblage A while 77.1 % (37/48) belonged to assemblage B. Although double peaks were observed at the chromatogram level, no mixed assemblage or sub-assemblage infections were demonstrated. Isolates of assemblage A mostly belonged to the sub-assemblage AII and showed similarity with previously described isolates. However, there was great genetic variability within assemblage B that showed heterogeneous nucleotide positions. Fifteen of them were new genotypes: 5 at the triose phosphate isomerase (tpi), 2 at the β-giardin (bg), and 8 at the glutamate dehydrogenase (gdh) genes.
  
  
  CONCLUSIONS
  Giardia duodenalis mainly assemblage B infection was predominant among the asymptomatic children in the study area. The high polymorphism found in isolates of assemblage B warrants a more defining tool to discriminate assemblage B at the sub-assemblage level. The findings of the present study indicate that there is a need to carry out national screening programs aiming to detect asymptomatic infections to minimize the reservoir of the disease.
authors.affiliation: Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia. tekluweg2007@yahoo.com.|College of Natural Sciences, Arba Minch University, Arba Minch, Ethiopia. tekluweg2007@yahoo.com.
authors.forename: Teklu
authors.initials: T
authors.lastname: Wegayehu
authors.affiliation: Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.|College of Animal Sciences and Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, China.
authors.forename: Md Robiul
authors.initials: MR
authors.lastname: Karim
authors.affiliation: College of Animal Sciences and Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, China.
authors.forename: Junqiang
authors.initials: J
authors.lastname: Li
authors.affiliation: Institute of Biotechnology, Addis Ababa University, Addis Ababa, Ethiopia.
authors.forename: Haileeyesus
authors.initials: H
authors.lastname: Adamu
authors.affiliation: Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
authors.forename: Berhanu
authors.initials: B
authors.lastname: Erko
authors.affiliation: College of Animal Sciences and Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, China.
authors.forename: Longxian
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
authors.forename: Getachew
authors.initials: G
authors.lastname: Tilahun
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D016054:DNA, Protozoan / Q000235:genetics; D005002:Ethiopia; D005243:Feces / Q000469:parasitology; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D016829:Giardia lamblia / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D005873:Giardiasis / Q000453:epidemiology* / Q000469:parasitology; D006801:Humans; D007223:Infant; D008297:Male; D058885:Multilocus Sequence Typing / Q000379:methods*; D010802:Phylogeny; D011110:Polymorphism, Genetic; D015995:Prevalence
chemical_list: D016054:DNA, Protozoan
keywords: Assemblages; Asymptomatic children; Ethiopia; Genetic diversity; Giardia duodenalis