title: Subtype analysis of Blastocystis sp. isolates from human and canine hosts in an urban community in the Philippines.
abstract: Blastocystis sp. is a common gut-dwelling protist of both humans and animals. A cross-sectional survey among humans and their dogs was conducted to determine the prevalence of Blastocystis infection and to characterize the subtype (ST) distribution in an urban community in the Philippines. Fecal specimens from 1,271 humans and 145 dogs were collected and inoculated in diphasic culture medium. Prevalence of Blastocystis by culture was 13.0% (95% CI = 11.2-15.0) and 14.5% (95% CI = 9.6-21.2) for humans and dogs, respectively. A total of 168 culture isolates were genotyped using polymerase chain reaction (PCR) with seven pairs of ST-specific sequence-tagged-site (STS) primers. In humans, the ST present in this study were ST1 with 22.6% (95% CI = 17.2-29.0), ST2 with 3.1% (95% CI = 1.3-6.7), ST3 with 41.4% (95% CI= 34.9-48.6), ST4 with 14.8% (95% CI = 10.5-20.6), ST5 with 4.1% (95% CI = 2.0-8.0), and unknown ST with 13.9% (95% CI = 9.6-19.4). In dogs, the ST present in this study were ST1 with 4.3% (95% CI = 0.0-29.0), ST2 with 8.7% (95% CI = 1.3-28.0), ST3 with 17.4% (95% CI = 6.4-37.7), ST4 with 13.0% (95% CI = 3.7-33.0), ST5 with 13.0% (95% CI = 3.7-33.0), and unknown ST with 47.8% (95% CI = 29.2-67.0). This is the first study that reported Blastocystis ST4 in human and canine hosts in the Philippines.
authors.affiliation: Department of Parasitology, College of Public Health, University of the Philippines, Ermita, Manila 1000, Philippines.
authors.forename: Maria Luz B
authors.initials: ML
authors.lastname: Belleza
authors.affiliation: College of Medicine, University of the Philippines, Ermita, Manila 1000, Philippines.
authors.forename: John Carlo B
authors.initials: JC
authors.lastname: Reyes
authors.affiliation: Department of Parasitology, College of Public Health, University of the Philippines, Ermita, Manila 1000, Philippines.
authors.forename: Pilarita N
authors.initials: PN
authors.lastname: Tongol-Rivera
authors.affiliation: Institute of Biology, College of Science, University of the Philippines, Diliman, Quezon City 1101, Philippines; Molecular Protozoology Laboratory, Natural Sciences Research Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines. Electronic address: wlrivera@science.upd.edu.ph.
authors.forename: Windell L
authors.initials: WL
authors.lastname: Rivera
mesh_terms: D000328:Adult; D000818:Animals; D016844:Blastocystis / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D016776:Blastocystis Infections / Q000453:epidemiology / Q000469:parasitology*; D003430:Cross-Sectional Studies; D004283:Dog Diseases / Q000453:epidemiology / Q000469:parasitology*; D004285:Dogs; D005243:Feces / Q000469:parasitology; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D010679:Philippines / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
keywords: Blastocystis; Dog; Human; Philippines; Subtype