title: Gut microbiota disturbance during helminth infection: can it affect cognition and behaviour of children?
abstract: Bidirectional signalling between the brain and the gastrointestinal tract is regulated at neural, hormonal, and immunological levels. Recent studies have shown that helminth infections can alter the normal gut microbiota. Studies have also shown that the gut microbiota is instrumental in the normal development, maturation and function of the brain. The pathophysiological pathways by which helminth infections contribute to altered cognitive function remain poorly understood.
  
  
  
  We put forward the hypothesis that gastrointestinal infections with parasitic worms, such as helminths, induce an imbalance of the gut-brain axis, which, in turn, can detrimentally manifest in brain development. Factors supporting this hypothesis are: 1) research focusing on intelligence and school performance in school-aged children has shown helminth infections to be associated with cognitive impairment, 2) disturbances in gut microbiota have been shown to be associated with important cognitive developmental effects, and 3) helminth infections have been shown to alter the gut microbiota structure. Evidence on the complex interactions between extrinsic (parasite) and intrinsic (host-derived) factors has been synthesised and discussed. While evidence in favour of the helminth-gut microbiota-central nervous system hypothesis is circumstantial, it would be unwise to rule it out as a possible mechanism by which gastrointestinal helminth infections induce childhood cognitive morbidity. Further empirical studies are necessary to test an indirect effect of helminth infections on the modulation of mood and behaviour through its effects on the gut microbiota.
authors.affiliation: School of Veterinary Science, University of Queensland, Gatton, 4343, QLD, Australia.
authors.forename: Vanina
authors.initials: V
authors.lastname: Guernier
authors.affiliation: School of Public Health, University of Queensland, Herston, 4006, QLD, Australia.|Princess Alexandra Hospital, Metro South Health and Hospital Services, Brisbane, Australia.
authors.forename: Bradley
authors.initials: B
authors.lastname: Brennan
authors.affiliation: Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Laith
authors.initials: L
authors.lastname: Yakob
authors.affiliation: School of Public Health, University of Queensland, Herston, 4006, QLD, Australia.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Milinovich
authors.affiliation: Research School of Population Health, Australian National University, Canberra, Australia.
authors.forename: Archie C A
authors.initials: AC
authors.lastname: Clements
authors.affiliation: School of Veterinary Science, University of Queensland, Gatton, 4343, QLD, Australia. r.magalhaes@uq.edu.au.|Children's Health Research Centre, University of Queensland, South Brisbane, 4101, QLD, Australia. r.magalhaes@uq.edu.au.
authors.forename: Ricardo J
authors.initials: RJ
authors.lastname: Soares Magalhaes
mesh_terms: D000293:Adolescent; D001921:Brain; D002490:Central Nervous System; D002648:Child; D002657:Child Development; D003071:Cognition; D060825:Cognitive Dysfunction / Q000382:microbiology / Q000469:parasitology / Q000523:psychology*; D064806:Dysbiosis / Q000382:microbiology / Q000469:parasitology / Q000523:psychology*; D000069196:Gastrointestinal Microbiome; D006373:Helminthiasis / Q000382:microbiology / Q000523:psychology*; D006801:Humans; D007411:Intestinal Diseases, Parasitic / Q000382:microbiology / Q000523:psychology*
keywords: Central nervous system; Development; Gut microbiota; Helminths; Mental health; Microbiota-gut-brain axis