title: Does vitamin A supplementation protect schoolchildren from acquiring soil-transmitted helminthiasis? A randomized controlled trial.
abstract: BACKGROUND
  Despite the intensive global efforts to control intestinal parasitic infections, the prevalence of soil-transmitted helminth (STH) infections is still very high in many developing countries particularly among children in rural areas.
  
  
  METHODS
  A randomized, double-blind, placebo-controlled trial was conducted on 250 Aboriginal schoolchildren in Malaysia to investigate the effects of a single high-dose of vitamin A supplementation (200,000 IU) on STH reinfection. The effect of the supplement was assessed at 3 and 6 months after receiving interventions; after a complete 3-day deworming course of 400 mg/daily of albendazole tablets.
  
  
  RESULTS
  Almost all children (98.6%) were infected with at least one STH species. The overall prevalence of ascariasis, trichuriasis and hookworm infection was 67.8%, 95.5% and 13.4%, respectively. Reinfection rates of Ascaris, Trichuris and hookworm were high; at 6 months, assessment reached 80% of the prevalence reported before treatment. There were no significant differences in the reinfection rates and intensities of STH between vitamin A supplemented-children and those who received placebo at 3 and 6 months (p > 0.05).
  
  
  CONCLUSIONS
  Vitamin A supplementation showed no protective effect against STH reinfection and this could be due to the high endemicity of STH in this community. Long-term interventions to reduce poverty will help significantly in reducing this continuing problem and there is no doubt that reducing intestinal parasitic infection would have a positive impact on the health, nutrition and education of these children.
  
  
  BACKGROUND
  This trial was registered at clinicaltrials.gov as NCT00936091.
authors.affiliation: Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia. halmekhlafi@yahoo.com.
authors.forename: Hesham M
authors.initials: HM
authors.lastname: Al-Mekhlafi
authors.forename: Tengku Shahrul
authors.initials: TS
authors.lastname: Anuar
authors.forename: Ebtesam M
authors.initials: EM
authors.lastname: Al-Zabedi
authors.forename: Mohamed T
authors.initials: MT
authors.lastname: Al-Maktari
authors.forename: Mohammed A K
authors.initials: MA
authors.lastname: Mahdy
authors.forename: Abdulhamid
authors.initials: A
authors.lastname: Ahmed
authors.forename: Atiya A
authors.initials: AA
authors.lastname: Sallam
authors.forename: Wan Ariffin
authors.initials: WA
authors.lastname: Abdullah
authors.forename: Norhayati
authors.initials: N
authors.lastname: Moktar
authors.forename: Johari
authors.initials: J
authors.lastname: Surin
mesh_terms: D015766:Albendazole / Q000008:administration & dosage / Q000627:therapeutic use; D000871:Anthelmintics / Q000008:administration & dosage / Q000627:therapeutic use; D002648:Child; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005260:Female; D006373:Helminthiasis / Q000188:drug therapy* / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D008296:Malaysia / Q000453:epidemiology; D008297:Male; D012987:Soil / Q000469:parasitology*; D014801:Vitamin A / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D000871:Anthelmintics; D012987:Soil; D014801:Vitamin A; D015766:Albendazole