title: Description of an epizootic and persistence of Streptococcus equi infections in horses.
abstract: The age-specific attack rates of Streptococcus equi infections of the upper respiratory tract and lymph nodes (strangles) in horses for the different age groups were 17.6% for broodmares, 47.5% for 1-year-old horses, and 37.5% for foals. Streptococcus equi was isolated from nasal, pharyngeal, or lymph node specimens in 31 (60.8%) of 51 sick horses. A male 1-year-old horse, shipped from Kentucky to farm A, was considered to be the index case. Six (19.4%) of 31 horses with strangles remained as shedders of S equi after clinical signs of the disease had ended. Shedders of S equi were not identified from horses that were exposed to infected horses but never developed strangles.
authors.affiliation: Department of Clinical Studies, New Bolton Center, University of Pennsylvania, Kennett Square 19348.
authors.forename: C R
authors.initials: CR
authors.lastname: Sweeney
authors.forename: C E
authors.initials: CE
authors.lastname: Benson
authors.forename: R H
authors.initials: RH
authors.lastname: Whitlock
authors.forename: D A
authors.initials: DA
authors.lastname: Meirs
authors.forename: S O
authors.initials: SO
authors.lastname: Barningham
authors.forename: S C
authors.initials: SC
authors.lastname: Whitehead
authors.forename: D
authors.initials: D
authors.lastname: Cohen
mesh_terms: D000818:Animals; D001428:Bacterial Vaccines; D004196:Disease Outbreaks / Q000662:veterinary*; D005260:Female; D006734:Horse Diseases / Q000453:epidemiology* / Q000517:prevention & control; D006736:Horses; D008297:Male; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000517:prevention & control / Q000662:veterinary*; D013290:Streptococcal Infections / Q000453:epidemiology / Q000517:prevention & control / Q000662:veterinary*; D013291:Streptococcus / Q000276:immunology; D014611:Vaccination / Q000662:veterinary
chemical_list: D001428:Bacterial Vaccines