title: Ascaris lumbricoides egg die-off in an experimental excreta storage system and public health implication in Vietnam.
abstract: OBJECTIVE
  We studied the influence of different additive materials (lime, and rice husk) and aeration conditions on Ascaris lumbricoides egg die-off in 24 vaults of an experimental excreta storage unit.
  
  
  METHODS
  Excreta samples were collected once every two weeks over a 181-day period. Temperature, pH, and moisture content were recorded. A. lumbricoides eggs were quantitatively analyzed by the Romanenko method, which identified and counted live and dead eggs.
  
  
  RESULTS
  From the first sampling (0 storage day) to the final sampling (181 storage days) the average percentage of viable A. lumbricoides eggs decreased gradually from 76.72 ± 11.23% (mean ± SD) to 8.26 ± 5.20%. The storage time and the high pH value significantly increased the die-off of helminth eggs. Over 181 storage days, all vaults option effectively reduced A. lumbricoides eggs die-off.
  
  
  CONCLUSIONS
  The best vault option, with aeration and 10% lime per total weight, met the WHO standard for excreta treatment on the 111th storage day.
authors.affiliation: Center for Public Health and Ecosystem Research (CENPHER), Hanoi University of Public Health, Hanoi, Vietnam. vuvantu@gmail.com.|Hoa Binh Provincial General Hospital, Hoa Binh, Vietnam. vuvantu@gmail.com.|Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland. vuvantu@gmail.com.|University of Basel, Basel, Switzerland. vuvantu@gmail.com.
authors.forename: Tu
authors.initials: T
authors.lastname: Vu-Van
authors.affiliation: Center for Public Health and Ecosystem Research (CENPHER), Hanoi University of Public Health, Hanoi, Vietnam.
authors.forename: Phuc
authors.initials: P
authors.lastname: Pham-Duc
authors.affiliation: Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.|University of Basel, Basel, Switzerland.
authors.forename: Mirko S
authors.initials: MS
authors.lastname: Winkler
authors.affiliation: Department of Water and Sanitation in Developing Countries (Sandec), Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Zurbrügg
authors.affiliation: Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.|University of Basel, Basel, Switzerland.
authors.forename: Jakob
authors.initials: J
authors.lastname: Zinsstag
authors.affiliation: Hanoi University of Public Health, Hanoi, Vietnam.
authors.forename: Huong
authors.initials: H
authors.lastname: Le Thi Thanh
authors.affiliation: Hanoi University of Public Health, Hanoi, Vietnam.
authors.forename: Tran Huu
authors.initials: TH
authors.lastname: Bich
authors.affiliation: Center for Public Health and Ecosystem Research (CENPHER), Hanoi University of Public Health, Hanoi, Vietnam.|International Livestock Research Institute, Hanoi, Vietnam.
authors.forename: Hung
authors.initials: H
authors.lastname: Nguyen-Viet
mesh_terms: D000818:Animals; D001196:Ascariasis / Q000517:prevention & control; D017164:Ascaris lumbricoides / Q000502:physiology*; D017610:Calcium Compounds / Q000737:chemistry; D005243:Feces / Q000737:chemistry / Q000469:parasitology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D012275:Oryza; D010087:Oxides / Q000737:chemistry; D010270:Parasite Egg Count; D013696:Temperature; D013997:Time Factors; D014744:Vietnam; D018505:Waste Management / Q000379:methods*
chemical_list: D017610:Calcium Compounds; D010087:Oxides; C016538:lime
keywords: Ascaris lumbricoides; Helminth; Human excreta; Vietnam; Waste reuse