title: Reductions in neonatal listeriosis: "Collateral benefit" of Group B streptococcal prophylaxis?
abstract: OBJECTIVE
  We tested the hypothesis that declines in Listeria monocytogenes in infants are related to declines in rates of early-onset Group B Streptococcus (GBS) infections associated with widespread prophylaxis using agents with Listeria activity.
  
  
  METHODS
  We performed a retrospective cohort analysis using a national administrative database Pediatric Health Information System (PHIS). We searched for ICD-9 codes for Listeriosis in infants <30 days old and for early-onset GBS infection of any kind in infants <5 days old during the study period.
  
  
  RESULTS
  We identified 183 cases of Listeriosis in infants <30 days in the PHIS database from 1992 to 2013. We noted a statistically significant decline in case rates over the years studied: 4.78 cases per 10,000 admissions (1992-1995) to 2.24 (1996-2002) to 1.31 from (2003-2013) (p < 0.0001). Case rates of early-onset GBS dropped significantly over the study period: 30.10 cases per 1000 admissions (1992-1995) to 21.70 (1996-2002) to 18.57 (2003-2013) (p < 0.0001). There was a statistically significant correlation between yearly rates of Listeriosis and early-onset GBS (rho: 0.53; p = 0.01).
  
  
  CONCLUSIONS
  These results support the hypothesis of a "collateral benefit" to widespread GBS prophylaxis and further support the position that empiric antibiotic regimens for febrile infants may no longer require Listeria activity.
authors.affiliation: Department of Quality and Safety, USA; Division of Infectious Diseases, Children's Mercy Hospital and Clinics, Kansas City, MO, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Lee
authors.affiliation: Department of Quality and Safety, USA; Division of Infectious Diseases, Children's Mercy Hospital and Clinics, Kansas City, MO, USA.
authors.forename: Jason G
authors.initials: JG
authors.lastname: Newland
authors.affiliation: Division of Infectious Diseases, Department of Pediatrics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA. Electronic address: ravi.jhaveri@unc.edu.
authors.forename: Ravi
authors.initials: R
authors.lastname: Jhaveri
mesh_terms: D019072:Antibiotic Prophylaxis / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D017053:Infection Control / Q000379:methods*; D008088:Listeriosis / Q000453:epidemiology*; D008297:Male; D012189:Retrospective Studies; D013290:Streptococcal Infections / Q000382:microbiology / Q000517:prevention & control*; D013291:Streptococcus; D013292:Streptococcus agalactiae / Q000187:drug effects*
keywords: Ampicillin; Group B streptococcus; Infants; Listeria monocytogenes; Listeriosis; Streptococcus agalactiae