title: Epidemiology of coinfection with soil transmitted helminths and Plasmodium falciparum among school children in Bumula District in western Kenya.
abstract: BACKGROUND
  Many school children living in Africa are infected with plasmodia and helminth species and are consequently at risk of coinfection. However, the epidemiology of such coinfection and the implications of coinfection for children's health remain poorly understood. This study describes the epidemiology of Ascaris lumbricoides-Plasmodium and hookworm-Plasmodium coinfection among school children living in western Kenya and investigates the associated risk factors.
  
  
  METHODS
  As part of a randomized trial, a baseline cross-sectional survey was conducted among school children aged 5-18 years in 23 schools in Bumula District. Single stool samples were collected to screen for helminth infections using the Kato-Katz technique and malaria parasitaemia was determined from a finger prick blood sample. Demographic and anthropometric data were also collected.
  
  
  RESULTS
  Overall, 46.4% of the children were infected with Plasmodium falciparum while 27.6% of the children were infected with at least one soil transmitted helminth (STH) species, with hookworm being the most common (16.8%) followed by A. lumbricoides (15.3%). Overall 14.3% of the children had STH-Plasmodium coinfection, with hookworm-Plasmodium (9.0%) coinfection being the most common. Geographical variation in the prevalence of coinfection occurred between schools. In multivariable logistic regression analysis, hookworm was positively associated with P. falciparum infection. In stratified analysis, hookworm infection was associated with increased odds of P. falciparum infection among both boys (P < 0.001) and girls (P = 0.01), whereas there was no association between A. lumbricoides and P. falciparum.
  
  
  CONCLUSIONS
  These findings demonstrate STH infections are still prevalent, despite the ongoing national deworming programme in Kenya, and that malaria parasitaemia is widespread, such that coinfection occurs among a proportion of children. A subsequent trial will allow us to investigate the implications of coinfection for the risk of clinical malaria.
authors.affiliation: College of Health Sciences, Makerere University, Kampala, Uganda. stellakepha2005@yahoo.com.|Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya. stellakepha2005@yahoo.com.
authors.forename: Stella
authors.initials: S
authors.lastname: Kepha
authors.affiliation: College of Health Sciences, Makerere University, Kampala, Uganda. nuwahaf@yahoo.co.uk.
authors.forename: Fred
authors.initials: F
authors.lastname: Nuwaha
authors.affiliation: London School of Hygiene & Tropical Medicine, London, UK. birgit.nikolay@lshtm.ac.uk.
authors.forename: Birgit
authors.initials: B
authors.lastname: Nikolay
authors.affiliation: Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya. paulmgichuki@gmail.com.
authors.forename: Paul
authors.initials: P
authors.lastname: Gichuki
authors.affiliation: London School of Hygiene & Tropical Medicine, London, UK. tansy.edwards@lshtm.ac.uk.
authors.forename: Tansy
authors.initials: T
authors.lastname: Edwards
authors.affiliation: London School of Hygiene & Tropical Medicine, London, UK. elizabeth.allen@lshtm.ac.uk.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Allen
authors.affiliation: Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya. snjenga@kemri.org.
authors.forename: Sammy M
authors.initials: SM
authors.lastname: Njenga
authors.affiliation: Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya. cmwandawiro@kemri.org.
authors.forename: Charles S
authors.initials: CS
authors.lastname: Mwandawiro
authors.affiliation: London School of Hygiene & Tropical Medicine, London, UK. simon.brooker@lshtm.ac.uk.|KEMRI-Wellcome Trust Research Programme, Nairobi, Kenya. simon.brooker@lshtm.ac.uk.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Brooker
mesh_terms: D000293:Adolescent; D000818:Animals; D002648:Child; D002675:Child, Preschool; D060085:Coinfection / Q000453:epidemiology* / Q000469:parasitology / Q000635:transmission; D003430:Cross-Sectional Studies; D005260:Female; D006373:Helminthiasis / Q000453:epidemiology* / Q000469:parasitology / Q000635:transmission; D006376:Helminths / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D006801:Humans; D007630:Kenya / Q000453:epidemiology; D016778:Malaria, Falciparum / Q000453:epidemiology* / Q000469:parasitology / Q000635:transmission; D008297:Male; D010963:Plasmodium falciparum / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D015995:Prevalence; D012574:Schools / Q000706:statistics & numerical data; D012987:Soil / Q000469:parasitology*; D055815:Young Adult
chemical_list: D012987:Soil