title: Using PCR-based detection and genotyping to trace Streptococcus salivarius meningitis outbreak strain to oral flora of radiology physician assistant.
abstract: We recently investigated three cases of bacterial meningitis that were reported from a midwestern radiology clinic where facemasks were not worn during spinal injection of contrast agent during myelography procedures. Using pulsed field gel electrophoresis we linked a case strain of S. salivarius to an oral specimen of a radiology physician assistant (RPA). We also used a real-time PCR assay to detect S. salivarius DNA within a culture-negative cerebrospinal fluid (CSF) specimen. Here we extend this investigation through using a nested PCR/sequencing strategy to link the culture-negative CSF specimen to the case strain. We also provide validation of the real-time PCR assay used, demonstrating that it is not solely specific for Streptococcus salivarius, but is also highly sensitive for detection of the closely related oral species Streptococcus vestibularis. Through using multilocus sequence typing and 16S rDNA sequencing we further strengthen the link between the CSF case isolate and the RPA carriage isolate. We also demonstrate that the newly characterized strains from this study are distinct from previously characterized S. salivarius strains associated with carriage and meningitis.
authors.affiliation: Respiratory Diseases Branch, Division of Bacterial Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Velusamy
authors.initials: V
authors.lastname: Srinivasan
authors.forename: Robert E
authors.initials: RE
authors.lastname: Gertz
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Shewmaker
authors.forename: Sarah
authors.initials: S
authors.lastname: Patrick
authors.forename: Amit S
authors.initials: AS
authors.lastname: Chitnis
authors.forename: Heather
authors.initials: H
authors.lastname: O'Connell
authors.forename: Isaac
authors.initials: I
authors.lastname: Benowitz
authors.forename: Priti
authors.initials: P
authors.lastname: Patel
authors.forename: Alice Y
authors.initials: AY
authors.lastname: Guh
authors.forename: Judith
authors.initials: J
authors.lastname: Noble-Wang
authors.forename: George
authors.initials: G
authors.lastname: Turabelidze
authors.forename: Bernard
authors.initials: B
authors.lastname: Beall
mesh_terms: D000483:Alleles; D002555:Cerebrospinal Fluid / Q000382:microbiology; D003428:Cross Infection / Q000453:epidemiology* / Q000517:prevention & control; D004269:DNA, Bacterial / Q000235:genetics; D004196:Disease Outbreaks / Q000517:prevention & control / Q000706:statistics & numerical data*; D005838:Genotype; D006801:Humans; D017053:Infection Control / Q000458:organization & administration*; D017757:Infectious Disease Transmission, Professional-to-Patient / Q000517:prevention & control*; D008581:Meningitis / Q000382:microbiology*; D010823:Physician Assistants; D016133:Polymerase Chain Reaction / Q000379:methods*; D011871:Radiology; D013291:Streptococcus / Q000378:metabolism*; D000078329:Workforce
chemical_list: D004269:DNA, Bacterial