title: Strongyloides stercoralis: Global Distribution and Risk Factors.
abstract: BACKGROUND
  The soil-transmitted threadworm, Strongyloides stercoralis, is one of the most neglected among the so-called neglected tropical diseases (NTDs). We reviewed studies of the last 20 years on S. stercoralis's global prevalence in general populations and risk groups.
  
  
  RESULTS
  A literature search was performed in PubMed for articles published between January 1989 and October 2011. Articles presenting information on infection prevalence were included. A Bayesian meta-analysis was carried out to obtain country-specific prevalence estimates and to compare disease odds ratios in different risk groups taking into account the sensitivities of the diagnostic methods applied. A total of 354 studies from 78 countries were included for the prevalence calculations, 194 (62.4%) were community-based studies, 121 (34.2%) were hospital-based studies and 39 (11.0%) were studies on refugees and immigrants. World maps with country data are provided. In numerous African, Asian and South-American resource-poor countries, information on S. stercoralis is lacking. The meta-analysis showed an association between HIV-infection/alcoholism and S. stercoralis infection (OR: 2.17 BCI: 1.18-4.01; OR: 6.69; BCI: 1.47-33.8), respectively.
  
  
  CONCLUSIONS
  Our findings show high infection prevalence rates in the general population in selected countries and geographical regions. S. stercoralis infection is prominent in several risk groups. Adequate information on the prevalence is still lacking from many countries. However, current information underscore that S. stercoralis must not be neglected. Further assessments in socio-economic and ecological settings are needed and integration into global helminth control is warranted.
authors.affiliation: Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.
authors.forename: Fabian
authors.initials: F
authors.lastname: Schär
authors.forename: Ulf
authors.initials: U
authors.lastname: Trostdorf
authors.forename: Federica
authors.initials: F
authors.lastname: Giardina
authors.forename: Virak
authors.initials: V
authors.lastname: Khieu
authors.forename: Sinuon
authors.initials: S
authors.lastname: Muth
authors.forename: Hanspeter
authors.initials: H
authors.lastname: Marti
authors.forename: Penelope
authors.initials: P
authors.lastname: Vounatsou
authors.forename: Peter
authors.initials: P
authors.lastname: Odermatt
mesh_terms: D000818:Animals; D014943:Global Health; D006801:Humans; D058069:Neglected Diseases / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D017171:Strongyloides stercoralis / Q000302:isolation & purification*; D013322:Strongyloidiasis / Q000453:epidemiology*; D019371:Topography, Medical