title: Infections in infants during the first 12 months of life: role of placental malaria and environmental factors.
abstract: BACKGROUND
  The association between placental malaria (PM) and first peripheral parasitaemias in early infancy was assessed in Tori Bossito, a rural area of Benin with a careful attention on transmission factors at an individual level.
  
  
  METHODS
  Statistical analysis was performed on 550 infants followed weekly from birth to 12 months. Malaria transmission was assessed by anopheles human landing catches every 6 weeks in 36 sampling houses and season defined by rainfall. Each child was located by GPS and assigned to the closest anopheles sampling house. Data were analysed by survival Cox models, stratified on the possession of insecticide-treated mosquito nets (ITNs) at enrolment.
  
  
  RESULTS
  Among infants sleeping in a house with an ITN, PM was found to be highly associated to first malaria infections, after adjusting on season, number of anopheles, antenatal care (ANC) visits and maternal severe anaemia. Infants born from a malaria infected placenta had a 2.13 fold increased risk to present a first malaria infection than those born from a non infected placenta ([1.24-3.67], p<0.01) when sleeping in a house with an ITN. The risk to present a first malaria infection was increased by 3.2 to 6.5, according to the level of anopheles exposure (moderate or high levels, compared to the absence of anopheles).
  
  
  CONCLUSIONS
  First malaria infections in early childhood can be attributed simultaneously to both PM and high levels of exposure to infected anopheles. Protective measures as Intermittent Preventive Treatment during pregnancy (IPTp) and ITNs, targeted on both mothers and infants should be reinforced, as well as the research on new drugs and insecticides. In parallel, investigations on placental malaria have to be strengthened to better understand the mechanisms involved, and thus to protect adequately the infants high risk group.
authors.affiliation: UMR216 Mère et enfant face aux infections tropicales, Institut de Recherche pour le Développement, Paris, France. agnesleport@yahoo.fr
authors.forename: Agnès
authors.initials: A
authors.lastname: Le Port
authors.forename: Laurence
authors.initials: L
authors.lastname: Watier
authors.forename: Gilles
authors.initials: G
authors.lastname: Cottrell
authors.forename: Smaila
authors.initials: S
authors.lastname: Ouédraogo
authors.forename: Célia
authors.initials: C
authors.lastname: Dechavanne
authors.forename: Charlotte
authors.initials: C
authors.lastname: Pierrat
authors.forename: Antoine
authors.initials: A
authors.lastname: Rachas
authors.forename: Julie
authors.initials: J
authors.lastname: Bouscaillou
authors.forename: Aziz
authors.initials: A
authors.lastname: Bouraima
authors.forename: Achille
authors.initials: A
authors.lastname: Massougbodji
authors.forename: Benjamin
authors.initials: B
authors.lastname: Fayomi
authors.forename: Anne
authors.initials: A
authors.lastname: Thiébaut
authors.forename: Fabrice
authors.initials: F
authors.lastname: Chandre
authors.forename: Florence
authors.initials: F
authors.lastname: Migot-Nabias
authors.forename: Yves
authors.initials: Y
authors.lastname: Martin-Prevel
authors.forename: André
authors.initials: A
authors.lastname: Garcia
authors.forename: Michel
authors.initials: M
authors.lastname: Cot
mesh_terms: D000818:Animals; D000852:Anopheles; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D057148:Insecticide-Treated Bednets; D008288:Malaria / Q000453:epidemiology* / Q000209:etiology / Q000635:transmission*; D008297:Male; D010920:Placenta / Q000469:parasitology; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic
references.citation: Am J Trop Med Hyg. 2006 Nov;75(5):798-803
references.pmid: 17123968
references.citation: Am J Trop Med Hyg. 1999 Jul;61(1):2-8
references.pmid: 10432046
references.citation: Clin Infect Dis. 2009 Feb 15;48(4):497-8; author reply 498-9
references.pmid: 19586381
references.citation: Am J Clin Nutr. 2004 Jul;80(1):193-8
references.pmid: 15213048
references.citation: J Clin Microbiol. 2005 Aug;43(8):3630-5
references.pmid: 16081889
references.citation: Mol Biochem Parasitol. 2007 Jan;151(1):1-8
references.pmid: 17081634
references.citation: Proc Natl Acad Sci U S A. 2004 Feb 24;101(8):2375-80
references.pmid: 14983017
references.citation: Cochrane Database Syst Rev. 2004;(2):CD000363
references.pmid: 15106149
references.citation: Am J Trop Med Hyg. 2004 Aug;71(2 Suppl):80-6
references.pmid: 15331822
references.citation: PLoS Med. 2009 Jul;6(7):e1000116
references.pmid: 19636353
references.citation: Malar J. 2008 Jul 03;7:117
references.pmid: 18598342
references.citation: J Clin Microbiol. 2005 Jun;43(6):2980-3
references.pmid: 15956437
references.citation: Malar J. 2010 Dec 31;9:380
references.pmid: 21194470
references.citation: Am J Epidemiol. 1997 Nov 15;146(10):826-31
references.pmid: 9384203
references.citation: Malar J. 2010 Oct 06;9:269
references.pmid: 20925928
references.citation: Trans R Soc Trop Med Hyg. 2000 Mar-Apr;94(2):159-63
references.pmid: 10897355
references.citation: Parasit Vectors. 2010 Sep 06;3:83
references.pmid: 20819214
references.citation: PLoS Med. 2005 Dec;2(12):e407
references.pmid: 16259531
references.citation: Trans R Soc Trop Med Hyg. 1998 Jan-Feb;92(1):12-20
references.pmid: 9692138
references.citation: Clin Infect Dis. 2008 Oct 15;47(8):1017-25
references.pmid: 18781874
references.citation: Malar J. 2006 Mar 23;5:21
references.pmid: 16556321
references.citation: Am J Trop Med Hyg. 2009 Feb;80(2):202-8
references.pmid: 19190214