title: Carriage of antibiotic-resistant bacteria by healthy children.
abstract: The frequency of carriage of antibiotic-resistant bacteria in healthy 7- and 8-year-old children in Bristol was studied. Children born in Avon between 1 April 1991 and 31 December 1992, attending the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) 7 year follow-up clinic, formed the study population. Carriage was estimated using mouth and stool samples. None of 105 children on whom information was available had received tetracycline, chloramphenicol, ciprofloxacin or an extended-spectrum cephalosporin in the previous year. Staphylococcus aureus was isolated from mouthwashes from 200 (37.1%) of 539 children sampled. Six (3%) of the isolates were resistant to chloramphenicol or tetracycline and four (2%) were methicillin resistant. Haemophilus spp. were isolated from 369 (72%) of 513 samples and 63 (17%) were ampicillin resistant, 49 (13.3%) were erythromycin resistant and seven (1.9%) were tetracycline resistant. Branhamella catarrhalis was isolated from 333 (74%) of 450 samples. Twenty-eight (8.4%) were erythromycin resistant and 14 (4.2%) strains were tetracycline resistant. Group A beta-haemolytic streptococci were isolated from 17 of 507 children sampled. One (5.9%) was tetracycline resistant. Stool samples were returned from 335 (62%) of 539 children from whom they were requested. Eleven per cent of samples yielded Gram-negative bacilli with high-level resistance to chloramphenicol, which was frequently linked to resistance to ampicillin, spectinomycin and streptomycin. Isolates demonstrating resistance to the third-generation cephalosporin ceftazidime were recovered from 17 subjects (3.2%). Six (35%) of 17 isolates possessed extended-spectrum beta-lactamases. Healthy children carry bacteria resistant to antibiotics to which children are not usually exposed. Resistance to ceftazidime, chloramphenicol and tetracycline may be co-selected by exposure to other antibiotics used in children or may be acquired from family members, pets, other children or food. These results suggest that antibiotic-resistant bacteria are widely disseminated and may be acquired by children before exposure to specific selection pressure.
authors.affiliation: Department of Microbiology, The Royal London Hospital, Barts and The London NHS Trust, Whitechapel Road, London E1 1BB, UK. M.R.Millar@mds.qmw.ac.uk
authors.forename: M R
authors.initials: MR
authors.lastname: Millar
authors.forename: T R
authors.initials: TR
authors.lastname: Walsh
authors.forename: C J
authors.initials: CJ
authors.lastname: Linton
authors.forename: S
authors.initials: S
authors.lastname: Zhang
authors.forename: J P
authors.initials: JP
authors.lastname: Leeming
authors.forename: P M
authors.initials: PM
authors.lastname: Bennett
mesh_terms: D001419:Bacteria / Q000187:drug effects*; D002353:Carrier State / Q000382:microbiology*; D002442:Ceftazidime / Q000494:pharmacology*; D002511:Cephalosporins / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D004352:Drug Resistance, Microbial; D004363:Drug Utilization; D004739:England; D005243:Feces / Q000382:microbiology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009055:Mouth / Q000382:microbiology*
chemical_list: D002511:Cephalosporins; D002442:Ceftazidime