title: Is household antibiotic use a risk factor for antibiotic-resistant pneumococcal infection?
abstract: We used microbiology and pharmacy data from health-maintenance organizations to determine whether antibiotic use by a household member increases the risk of penicillin-non-susceptible pneumococcal disease. Though it has been well established that an individual's antibiotic use increases one's risk of antibiotic-resistant infection, it is unclear whether the risk is increased if a member of one's household is exposed to antibiotics. We therefore conducted a case-control study of patients enrolled in health maintenance organizations in Western Washington and Northern California. Cases were defined as individuals with penicillin-non-susceptible pneumococcal infection; controls were individuals with penicillin-susceptible pneumococcal infection. Socioeconomic variables were obtained by linking addresses with 1997 census block group data. One-hundred and thirty-four cases were compared with 798 controls. Individual antibiotic use prior to diagnosis increased the odds of penicillin non-susceptibility, with the strongest effect seen for beta-lactam use within 2 months (OR 1.8, 95% CI 1.2, 2.8). When household antibiotic use by persons other than the patient were considered, at 4 months prior to diagnosis there was a trend towards an association between penicillin non-susceptibility and beta-lactam antibiotic use, and a possible association in a small subgroup of patients with eye and ear isolates. However, no significant overall pattern of association was seen. We conclude that though antibiotic use of any kind within 2 months prior to diagnosis is associated with an increased risk of penicillin-non-susceptible pneumococcal disease, there is no significant overall pattern of association between household antibiotic use and penicillin-non-susceptible pneumococcal infection.
authors.affiliation: Virginia Mason Medical Center Department of Pediatrics, Seattle, WA, USA.
authors.forename: T S
authors.initials: TS
authors.lastname: Kwan-Gett
authors.forename: R L
authors.initials: RL
authors.lastname: Davis
authors.forename: D K
authors.initials: DK
authors.lastname: Shay
authors.forename: S
authors.initials: S
authors.lastname: Black
authors.forename: H
authors.initials: H
authors.lastname: Shinefield
authors.forename: T
authors.initials: T
authors.lastname: Koepsell
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002140:California / Q000453:epidemiology; D016022:Case-Control Studies; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D010403:Penicillin Resistance; D011008:Pneumococcal Infections / Q000188:drug therapy*; D010818:Practice Patterns, Physicians'; D012307:Risk Factors; D012651:Self Medication; D014861:Washington / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents