title: Case-control study of hepatitis B and hepatitis C in older adults: Do healthcare exposures contribute to burden of new infections?
abstract: Reports of hepatitis B virus (HBV) and hepatitis C virus (HCV) transmission associated with unsafe medical practices have been increasing in the United States. However, the contribution of healthcare exposures to the burden of new infections is poorly understood outside of recognized outbreaks. We conducted a case-control study at three health departments that perform enhanced viral hepatitis surveillance in New York and Oregon. Reported cases of symptomatic acute hepatitis B and hepatitis C occurring in persons≥55 years of age from 2006 to 2008 were enrolled. Controls were identified using telephone directories and matched to individual cases by age group (55-59, 60-69, and ≥70 years) and residential postal code. Data collection covered exposures within 6 months before symptom onset (cases) or date of interview (controls). Forty-eight (37 hepatitis B and 11 hepatitis C) case and 159 control patients were enrolled. Case patients were more likely than controls to report one or more behavioral risk exposures, including sexual or household contact with an HBV or HCV patient, >1 sex partner, illicit drug use, or incarceration (21% of cases versus 4% of controls exposed; matched odds ratio [mOR]=7.1; 95% confidence interval [CI]: 2.1, 24.1). Case patients were more likely than controls to report hemodialysis (8% of cases; mOR=13.0; 95% CI: 1.5, 115), injections in a healthcare setting (58%; mOR=2.7; 95% CI: 1.3, 5.3), and surgery (33%; mOR=2.3; 95% CI: 1.1, 4.7). In a multivariate model, behavioral risks (adjusted OR [aOR]=5.4; 95% CI: 1.5, 19.0; 17% attributable risk), injections (aOR=2.7; 95% CI: 1.3, 5.8; 37% attributable risk), and hemodialysis (aOR=11.5; 95% CI: 1.2, 107; 8% attributable risk) were associated with case status.
  
  
  CONCLUSIONS
  Healthcare exposures may represent an important source of new HBV and HCV infections among older adults.
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. JPERZ@CDC.GOV
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Perz
authors.forename: Scott
authors.initials: S
authors.lastname: Grytdal
authors.forename: Suzanne
authors.initials: S
authors.lastname: Beck
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Fireteanu
authors.forename: Tasha
authors.initials: T
authors.lastname: Poissant
authors.forename: Elena
authors.initials: E
authors.lastname: Rizzo
authors.forename: Katherine
authors.initials: K
authors.lastname: Bornschlegel
authors.forename: Ann
authors.initials: A
authors.lastname: Thomas
authors.forename: Sharon
authors.initials: S
authors.lastname: Balter
authors.forename: Jeremy
authors.initials: J
authors.lastname: Miller
authors.forename: R Monina
authors.initials: RM
authors.lastname: Klevens
authors.forename: Lyn
authors.initials: L
authors.lastname: Finelli
mesh_terms: D000208:Acute Disease; D017677:Age Distribution; D000368:Aged; D000553:Ambulatory Care / Q000706:statistics & numerical data*; D016022:Case-Control Studies; D004866:Equipment Contamination / Q000706:statistics & numerical data; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology* / Q000635:transmission*; D006526:Hepatitis C / Q000453:epidemiology* / Q000635:transmission*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007267:Injections / Q000009:adverse effects / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009518:New York / Q000453:epidemiology; D011159:Population Surveillance; D012307:Risk Factors; D017678:Sex Distribution; D014611:Vaccination / Q000009:adverse effects / Q000706:statistics & numerical data