title: Age-related changes in hookworm infection, anaemia and iron deficiency in an area of high Necator americanus hookworm transmission in south-eastern Brazil.
abstract: Surprisingly few detailed age-stratified data exist on the epidemiology of hookworm and iron status, especially in Latin America. We present data from a cross-sectional survey examining 1332 individuals aged 0-86 years from a community in south-east Brazil for hookworm, anaemia and iron deficiency. Sixty-eight percent of individuals were infected with the human hookworm Necator americanus. The force of infection (lambda=0.354) was similar to estimates from other areas of high hookworm transmission. Individuals from poorer households had significantly higher prevalence and intensity of infection than individuals from better-off households. The prevalence of anaemia, iron deficiency and iron-deficiency anaemia was 11.8%, 12.7% and 4.3%, respectively. Anaemia was most prevalent among young children and the elderly. Univariate analysis showed that haemoglobin and serum ferritin were both significantly negatively associated with hookworm intensity among both school-aged children and adults. Multivariate analysis showed that, after controlling for socio-economic status, iron indicators were significantly associated with heavy hookworm infection. Our results indicate that, even in areas where there is a low overall prevalence of anaemia, hookworm can still have an important impact on host iron status, especially in school-aged children and the elderly.
authors.affiliation: Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK. simon.brooker@lshtm.ac.uk
authors.forename: Simon
authors.initials: S
authors.lastname: Brooker
authors.forename: Anne
authors.initials: A
authors.lastname: Jardim-Botelho
authors.forename: Rupert J
authors.initials: RJ
authors.lastname: Quinnell
authors.forename: Stefan M
authors.initials: SM
authors.lastname: Geiger
authors.forename: Iramaya R
authors.initials: IR
authors.lastname: Caldas
authors.forename: Fiona
authors.initials: F
authors.lastname: Fleming
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Hotez
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Correa-Oliveira
authors.forename: Laura C
authors.initials: LC
authors.lastname: Rodrigues
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Bethony
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D018798:Anemia, Iron-Deficiency / Q000453:epidemiology*; D000818:Animals; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D017221:Necator americanus; D009332:Necatoriasis / Q000453:epidemiology*; D015995:Prevalence; D012044:Regression Analysis; D017678:Sex Distribution