title: Exposure to multiple parasites is associated with the prevalence of active convulsive epilepsy in sub-Saharan Africa.
abstract: BACKGROUND
  Epilepsy is common in developing countries, and it is often associated with parasitic infections. We investigated the relationship between exposure to parasitic infections, particularly multiple infections and active convulsive epilepsy (ACE), in five sites across sub-Saharan Africa.
  
  
  RESULTS
  A case-control design that matched on age and location was used. Blood samples were collected from 986 prevalent cases and 1,313 age-matched community controls and tested for presence of antibodies to Onchocerca volvulus, Toxocara canis, Toxoplasma gondii, Plasmodium falciparum, Taenia solium and HIV. Exposure (seropositivity) to Onchocerca volvulus (OR = 1.98; 95%CI: 1.52-2.58, p<0.001), Toxocara canis (OR = 1.52; 95%CI: 1.23-1.87, p<0.001), Toxoplasma gondii (OR = 1.28; 95%CI: 1.04-1.56, p = 0.018) and higher antibody levels (top tertile) to Toxocara canis (OR = 1.70; 95%CI: 1.30-2.24, p<0.001) were associated with an increased prevalence of ACE. Exposure to multiple infections was common (73.8% of cases and 65.5% of controls had been exposed to two or more infections), and for T. gondii and O. volvulus co-infection, their combined effect on the prevalence of ACE, as determined by the relative excess risk due to interaction (RERI), was more than additive (T. gondii and O. volvulus, RERI = 1.19). The prevalence of T. solium antibodies was low (2.8% of cases and 2.2% of controls) and was not associated with ACE in the study areas.
  
  
  CONCLUSIONS
  This study investigates how the degree of exposure to parasites and multiple parasitic infections are associated with ACE and may explain conflicting results obtained when only seropositivity is considered. The findings from this study should be further validated.
authors.affiliation: KEMRI/Wellcome Trust Research Programme, The Centre of Geographical Medicine Research - Coast, Kilifi, Kenya; Studies of the Epidemiology of Epilepsy in Demographic Surveillance Systems (SEEDS)-INDEPTH Network, Accra, Ghana.
authors.forename: Gathoni
authors.initials: G
authors.lastname: Kamuyu
authors.affiliation: Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom; MRC Tropical Epidemiology Group, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom; Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Christian
authors.initials: C
authors.lastname: Bottomley
authors.affiliation: KEMRI/Wellcome Trust Research Programme, The Centre of Geographical Medicine Research - Coast, Kilifi, Kenya; Egerton University, Nakuru, Kenya.
authors.forename: James
authors.initials: J
authors.lastname: Mageto
authors.affiliation: KEMRI/Wellcome Trust Research Programme, The Centre of Geographical Medicine Research - Coast, Kilifi, Kenya; Studies of the Epidemiology of Epilepsy in Demographic Surveillance Systems (SEEDS)-INDEPTH Network, Accra, Ghana; Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: Brett
authors.initials: B
authors.lastname: Lowe
authors.affiliation: Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, United States of America.
authors.forename: Patricia P
authors.initials: PP
authors.lastname: Wilkins
authors.affiliation: Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, United States of America.
authors.forename: John C
authors.initials: JC
authors.lastname: Noh
authors.affiliation: Laboratory of Parasitic Diseases. National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America.
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Nutman
authors.affiliation: KEMRI/Wellcome Trust Research Programme, The Centre of Geographical Medicine Research - Coast, Kilifi, Kenya; Studies of the Epidemiology of Epilepsy in Demographic Surveillance Systems (SEEDS)-INDEPTH Network, Accra, Ghana; Research Support Unit, Faculty of Health Sciences, Aga Khan University (East Africa), Nairobi, Kenya.
authors.forename: Anthony K
authors.initials: AK
authors.lastname: Ngugi
authors.affiliation: KEMRI/Wellcome Trust Research Programme, The Centre of Geographical Medicine Research - Coast, Kilifi, Kenya.
authors.forename: Rachael
authors.initials: R
authors.lastname: Odhiambo
authors.affiliation: MRC/Wits Rural Public Health & Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; Epidemiology and Public Health, Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden.
authors.forename: Ryan G
authors.initials: RG
authors.lastname: Wagner
authors.affiliation: Studies of the Epidemiology of Epilepsy in Demographic Surveillance Systems (SEEDS)-INDEPTH Network, Accra, Ghana; Iganga-Mayuge Health and Demographic Surveillance System, Iganga, Uganda; Department of Paediatrics and Child Health, Makerere University College of Health Sciences, Kampala, Uganda.
authors.forename: Angelina
authors.initials: A
authors.lastname: Kakooza-Mwesige
authors.affiliation: Kintampo Health Research Centre, Kintampo, Ghana.
authors.forename: Seth
authors.initials: S
authors.lastname: Owusu-Agyei
authors.affiliation: Kintampo Health Research Centre, Kintampo, Ghana.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Ae-Ngibise
authors.affiliation: Ifakara Health Institute, Ifakara, Tanzania.
authors.forename: Honorati
authors.initials: H
authors.lastname: Masanja
authors.affiliation: KEMRI/Wellcome Trust Research Programme, The Centre of Geographical Medicine Research - Coast, Kilifi, Kenya.
authors.forename: Faith H A
authors.initials: FH
authors.lastname: Osier
authors.affiliation: Swiss Tropical and Public Health Institute, Basel, Switzerland; Unversity of Basel, Basel, Switzerland.
authors.forename: Peter
authors.initials: P
authors.lastname: Odermatt
authors.affiliation: KEMRI/Wellcome Trust Research Programme, The Centre of Geographical Medicine Research - Coast, Kilifi, Kenya; Studies of the Epidemiology of Epilepsy in Demographic Surveillance Systems (SEEDS)-INDEPTH Network, Accra, Ghana; Neurosciences Unit, UCL Institute of Child Health, London, United Kingdom; Clinical Research Unit, London School of Hygiene and Tropical Medicine, London, United Kingdom; Department of Psychiatry, University of Oxford, Oxford, United Kingdom.
authors.forename: Charles R
authors.initials: CR
authors.lastname: Newton
mesh_terms: D000293:Adolescent; D000328:Adult; D017954:Africa South of the Sahara / Q000453:epidemiology; D000909:Antibodies, Helminth / Q000097:blood; D000913:Antibodies, Protozoan / Q000097:blood; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000150:complications / Q000453:epidemiology / Q000469:parasitology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D010272:Parasitic Diseases / Q000150:complications / Q000453:epidemiology / Q000469:parasitology; D015995:Prevalence; D016036:Seroepidemiologic Studies; D055815:Young Adult
chemical_list: D000909:Antibodies, Helminth; D000913:Antibodies, Protozoan