title: Mapping the Risk of Soil-Transmitted Helminthic Infections in the Philippines.
abstract: BACKGROUND
  In order to increase the efficient allocation of soil-transmitted helminth (STH) disease control resources in the Philippines, we aimed to describe for the first time the spatial variation in the prevalence of A. lumbricoides, T. trichiura and hookworm across the country, quantify the association between the physical environment and spatial variation of STH infection and develop predictive risk maps for each infection.
  
  
  RESULTS
  Data on STH infection from 35,573 individuals across the country were geolocated at the barangay level and included in the analysis. The analysis was stratified geographically in two major regions: 1) Luzon and the Visayas and 2) Mindanao. Bayesian geostatistical models of STH prevalence were developed, including age and sex of individuals and environmental variables (rainfall, land surface temperature and distance to inland water bodies) as predictors, and diagnostic uncertainty was incorporated. The role of environmental variables was different between regions of the Philippines. This analysis revealed that while A. lumbricoides and T. trichiura infections were widespread and highly endemic, hookworm infections were more circumscribed to smaller foci in the Visayas and Mindanao.
  
  
  CONCLUSIONS
  This analysis revealed significant spatial variation in STH infection prevalence within provinces of the Philippines. This suggests that a spatially targeted approach to STH interventions, including mass drug administration, is warranted. When financially possible, additional STH surveys should be prioritized to high-risk areas identified by our study in Luzon.
authors.affiliation: School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, Australia; Children's Health and Environment Program, Queensland Children's Medical Research Institute, The University of Queensland, Herston Campus, Herston, Australia; University of Queensland, Infectious Disease Epidemiology Unit, School of Population Health, Herston, Queensland, Australia.
authors.forename: Ricardo J
authors.initials: RJ
authors.lastname: Soares Magalhães
authors.affiliation: University of the Philippines Manila, College of Public Health, Department of Parasitology, Manila, Philippines.
authors.forename: Maria S
authors.initials: MS
authors.lastname: Salamat
authors.affiliation: University of the Philippines Manila, College of Public Health, Department of Parasitology, Manila, Philippines.
authors.forename: Lydia
authors.initials: L
authors.lastname: Leonardo
authors.affiliation: University of Queensland, Infectious Disease Epidemiology Unit, School of Population Health, Herston, Queensland, Australia; Research School of Population Health, The Australian National University, Canberra, Australian Capital Territory, Australia.
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Gray
authors.affiliation: Department of Biostatistics and Epidemiology, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America.
authors.forename: Hélène
authors.initials: H
authors.lastname: Carabin
authors.affiliation: Institute for Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia.
authors.forename: Kate
authors.initials: K
authors.lastname: Halton
authors.affiliation: Infectious Disease Division, QIMR-Berghoffer Medical Research Institute, Herston, Queensland, Australia.
authors.forename: Donald P
authors.initials: DP
authors.lastname: McManus
authors.affiliation: University of Queensland, Infectious Disease Epidemiology Unit, School of Population Health, Herston, Queensland, Australia.
authors.forename: Gail M
authors.initials: GM
authors.lastname: Williams
authors.affiliation: University of the Philippines Manila, College of Public Health, Department of Parasitology, Manila, Philippines.
authors.forename: Pilarita
authors.initials: P
authors.lastname: Rivera
authors.affiliation: University of the Philippines Manila, College of Public Health, Department of Epidemiology and Biostatistics, Manila, Philippines.
authors.forename: Ofelia
authors.initials: O
authors.lastname: Saniel
authors.affiliation: Philippine Department of Health, National Center for Disease Prevention and Control, Manila, Philippines.
authors.forename: Leda
authors.initials: L
authors.lastname: Hernandez
authors.affiliation: London School of Hygiene & Tropical Medicine, Department of Disease Control, London, United Kingdom.
authors.forename: Laith
authors.initials: L
authors.lastname: Yakob
authors.affiliation: International Health Institute, Brown University, Providence, Rhode Island, United States of America.
authors.forename: Stephen T
authors.initials: ST
authors.lastname: McGarvey
authors.affiliation: University of Queensland, Infectious Disease Epidemiology Unit, School of Population Health, Herston, Queensland, Australia; Research School of Population Health, The Australian National University, Canberra, Australian Capital Territory, Australia.
authors.forename: Archie C A
authors.initials: AC
authors.lastname: Clements
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000723:Ancylostomatoidea / Q000302:isolation & purification*; D000818:Animals; D017164:Ascaris lumbricoides / Q000302:isolation & purification*; D002648:Child; D002675:Child, Preschool; D002980:Climate; D005260:Female; D005843:Geography; D006373:Helminthiasis / Q000453:epidemiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007411:Intestinal Diseases, Parasitic / Q000453:epidemiology*; D008875:Middle Aged; D010679:Philippines / Q000453:epidemiology; D015995:Prevalence; D018570:Risk Assessment; D019371:Topography, Medical; D014258:Trichuris / Q000302:isolation & purification*; D055815:Young Adult