Incidence and risk factors of Giardia duodenalis infection in an orphanage, Thailand.
A cohort study was performed to evaluate the incidence and risk factors of Giardia duodenalis infection in an orphanage in suburban area outside Bangkok, central Thailand. Stool specimens were examined for the presence of G. duodenalis in January 2007, May 2007 and January 2008. Of 892 stool specimens from 481 individuals, simple wet preparation, PBS ethyl-acetate sedimentation and PCR amplification of the SSU-rRNA gene were performed to detect G. duodenalis. Using PCR of the glutamate dehydrogenase gene and sequence analysis, G. duodenalis assemblages were identified. Associated risk factors were analysed using Fisher's exact test which revealed significant infection of G. duodenalis in boys and specific rooms where orphans aged 25-48 months old lived. Genotypic characterization of G. duodenalis revealed that assemblage A subtype AII was the most predominant found in orphans living in the specific rooms, thus the transmission was likely to occur via person-to-person. Other modes of transmission were less likely to occur. This study showed that the incidence rate of Giardia infection gradually decreased significantly after the implementation of health education and appropriate treatment of infected orphans.
Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
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Boontanom
Department of Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Khlong Luang, Pathum Thani 12121, Thailand.
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Pipatsatitpong
Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
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Tan-Ariya
Department of Parasitology, Phramongkutklao College of Medicine, Ratchawithi Rd., Bangkok 10400, Thailand.
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Mungthin
Department of Parasitology, Phramongkutklao College of Medicine, Ratchawithi Rd., Bangkok 10400, Thailand.
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Siripattanapipong
Department of Parasitology, Phramongkutklao College of Medicine, Ratchawithi Rd., Bangkok 10400, Thailand.
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Naaglor
Department of Parasitology, Phramongkutklao College of Medicine, Ratchawithi Rd., Bangkok 10400, Thailand.
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Leelayoova
D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D015331:Cohort Studies; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005243:Feces / Q000469:parasitology; D005260:Female; D005838:Genotype; D016829:Giardia lamblia / Q000302:isolation & purification*; D005873:Giardiasis / Q000453:epidemiology* / Q000469:parasitology; D005969:Glutamate Dehydrogenase / Q000235:genetics; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008969:Molecular Sequence Data; D019372:Orphanages; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012307:Risk Factors; D017422:Sequence Analysis, DNA; D013383:Suburban Population; D013785:Thailand / Q000453:epidemiology
D016054:DNA, Protozoan; D004275:DNA, Ribosomal; D012337:RNA, Ribosomal, 18S; D005969:Glutamate Dehydrogenase