title: Incidence and risk factors of blastocystis infection in orphans at the Babies' Home, Nonthaburi Province, Thailand.
abstract: BACKGROUND
  Blastocystis infection is one of the most common intestinal protozoan infections reported in Thai population of all age groups for which epidemiological information is important to understand patterns of transmission for developing methods ofprevention and control for each specific group. The authors aimed to study prevalence, incidence and riskfactors associated with Blastocystis infection in orphans and childcare workers. Additionally, subtypes ofBlastocystis were identified
  
  
  METHODS
  A retrospective cohort study of Blastocystis sp. was conducted in orphans aged less than 5 years and their childcare workers at Babies' Home, Nonthaburi Province, Thailand. A base line survey was conducted in December 2009 and afollow-up survey was conducted in April 2010. A total of 336 and 331 stool samples were collected. Blastocystis infection was examined using short-term in vitro cultivation in Jones's medium supplemented with 10% fetal calf serum. To analyze subtypes ofBlastocystis sp., PCR-RFLP of the small subunit ribosomal RNA gene was performed.
  
  
  RESULTS
  Theprevalence ofBlastocystis infection in December 2009 and April 2010 were 8.1% and 13.3%, respectively The inlcidence rate ofBlastocystis infection was 1.6/100 person-months. Subtype analysis ofBlastocystis sp. in December 2009 and in April 2010 showed that subtype 3 was the most predominant (76% and 76%), followed by subtype 1 (16% and 20%), and unidentified subtype (8% and 4%), respectively. Subtype 3 is of human origin, thus person-to-person transmission is considered a major route ofBlastocystis infection in this population.
  
  
  CONCLUSIONS
  Person-to-person transmission of Blastocystis infection in orphans living in the same house had been proposed, thus the prevalence and incidence of Blastocystis infection could be used to reflect the hygienic condition in the orphanage. Infection prevention and control practice can be effectively implemented.
authors.forename: Jitrada
authors.initials: J
authors.lastname: Boondit
authors.forename: Duangnate
authors.initials: D
authors.lastname: Pipatsatitpong
authors.forename: Mathirut
authors.initials: M
authors.lastname: Mungthin
authors.forename: Paanjit
authors.initials: P
authors.lastname: Taamasri
authors.forename: Peerapan
authors.initials: P
authors.lastname: Tan-ariya
authors.forename: Tawee
authors.initials: T
authors.lastname: Naaglor
authors.forename: Saovanee
authors.initials: S
authors.lastname: Leelayoova
mesh_terms: D000293:Adolescent; D016844:Blastocystis / Q000235:genetics / Q000302:isolation & purification; D016776:Blastocystis Infections / Q000453:epidemiology* / Q000469:parasitology / Q000635:transmission; D002648:Child; D054540:Child, Orphaned / Q000706:statistics & numerical data; D002675:Child, Preschool; D015331:Cohort Studies; D018562:Disease Transmission, Infectious; D005243:Feces / Q000469:parasitology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D019372:Orphanages; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D013785:Thailand / Q000453:epidemiology