title: A Novel α-Hemolytic Streptococcus Species (Streptococcus azizii sp. nov.) Associated with Meningoencephalitis in Naïve Weanling C57BL/6 Mice.
abstract: During 1 year, experimentally naïve C57BL/6NCrl weanlings born to timed-pregnant dams from a single vendor demonstrated markedly increased mortality associated with runting, abnormal gait, and decreased activity. Gram-positive, aerobic, α-hemolytic, coccoid bacteria were isolated from the meninges (n = 16), blood (n = 1), and kidneys (n = 1) of clinically affected weanlings (n = 15); from the uterus (n = 1), meninges (n = 1), and oral cavity (n = 2) of 3 dams; and from the meninges and oral cavity of a clinically affected 86-d-old mouse in the same colony. Multifocal, necrosuppurative meningoencephalitis and ventriculitis with intralesional gram-positive coccoid bacteria were present in all but 2 affected animals. The bacterium also was isolated from the oral cavity of an asymptomatic timed-pregnant dam (1 of 23) from the same vendor and from 8 mice at the vendor's facility. All isolates (n = 25) were identified by using 2 semiautomated rapid-identification systems, one of which consistently identified the causative bacterium as Aerococcus viridans 2 (n = 12) or 3 (n = 13), with probabilities of 55.7% to 98.3%. The bacterium did not grow in 6.5% NaCl at 10 °C, thus suggesting a Streptococcus species. Partial 16S rRNA sequencing of 4 isolates suggested S. hyointestinalis (probability, 93.4%) and S. gallinaceus (99.5%). Full 16S rRNA sequences for 3 isolates identified the bacterium as a novel Streptococcus species most closely related to S. acidominimus strain LGM (96.5%) and Streptococcus species strain Smarlab 3301444 (96.3%) and for which we propose the name S. azizii.
authors.affiliation: Tri-Institutional Training Program in Laboratory Animal Medicine and Science, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, and The Rockefeller University, USA.
authors.forename: Gillian C
authors.initials: GC
authors.lastname: Braden
authors.affiliation: Tri-Institutional Training Program in Laboratory Animal Medicine and Science, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, USA. The Rockefeller University, Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College.
authors.forename: Rodolfo Ricart
authors.initials: RR
authors.lastname: Arbona
authors.affiliation: Tri-Institutional Training Program in Laboratory Animal Medicine and Science, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, USA; The Rockefeller University, Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College, USA; Laboratory for Comparative Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, and The Rockefeller University, New York, New York, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Lepherd
authors.affiliation: Tri-Institutional Training Program in Laboratory Animal Medicine and Science, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, USA; The Rockefeller University, Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College, USA; Laboratory for Comparative Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, and The Rockefeller University, New York, New York, USA.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Monette
authors.affiliation: Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College, Laboratory for Comparative Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, USA; The Rockefeller University, New York, New York, USA.
authors.forename: Aziz
authors.initials: A
authors.lastname: Toma
authors.affiliation: Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
authors.forename: James G
authors.initials: JG
authors.lastname: Fox
authors.affiliation: Department of Microbiology, The Forsyth Institute, Cambridge, Massachusetts, USA; Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts, USA.
authors.forename: Floyd E
authors.initials: FE
authors.lastname: Dewhirst
authors.affiliation: Tri-Institutional Training Program in Laboratory Animal Medicine and Science, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, USA; The Rockefeller University, Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College, USA.
authors.forename: Neil S
authors.initials: NS
authors.lastname: Lipman
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D008590:Meningoencephalitis / Q000382:microbiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D011247:Pregnancy; D013290:Streptococcal Infections / Q000382:microbiology*; D013291:Streptococcus / Q000472:pathogenicity*; D014886:Weaning