title: Shiga Toxin 1-Producing Shigella sonnei Infections, California, United States, 2014-2015.
abstract: Shiga toxins (Stx) are primarily associated with Shiga toxin-producing Escherichia coli and Shigella dysenteriae serotype 1. Stx production by other shigellae is uncommon, but in 2014, Stx1-producing S. sonnei infections were detected in California. Surveillance was enhanced to test S. sonnei isolates for the presence and expression of stx genes, perform DNA subtyping, describe clinical and epidemiologic characteristics of case-patients, and investigate for sources of infection. During June 2014-April 2015, we identified 56 cases of Stx1-producing S. sonnei, in 2 clusters. All isolates encoded stx1 and produced active Stx1. Multiple pulsed-field gel electrophoresis patterns were identified. Bloody diarrhea was reported by 71% of case-patients; none had hemolytic uremic syndrome. Some initial cases were epidemiologically linked to travel to Mexico, but subsequent infections were transmitted domestically. Continued surveillance of Stx1-producing S. sonnei in California is necessary to characterize its features and plan for reduction of its spread in the United States.
authors.forename: Katherine
authors.initials: K
authors.lastname: Lamba
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Nelson
authors.forename: Akiko C
authors.initials: AC
authors.lastname: Kimura
authors.forename: Alyssa
authors.initials: A
authors.lastname: Poe
authors.forename: Joan
authors.initials: J
authors.lastname: Collins
authors.forename: Annie S
authors.initials: AS
authors.lastname: Kao
authors.forename: Laura
authors.initials: L
authors.lastname: Cruz
authors.forename: Gregory
authors.initials: G
authors.lastname: Inami
authors.forename: Julie
authors.initials: J
authors.lastname: Vaishampayan
authors.forename: Alvaro
authors.initials: A
authors.lastname: Garza
authors.forename: Vishnu
authors.initials: V
authors.lastname: Chaturvedi
authors.forename: Duc J
authors.initials: DJ
authors.lastname: Vugia
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002140:California / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003967:Diarrhea / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D004405:Dysentery, Bacillary / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D016521:Electrophoresis, Gel, Pulsed-Field; D062665:Epidemiological Monitoring; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D022622:Shiga Toxin 1 / Q000096:biosynthesis* / Q000302:isolation & purification; D012764:Shigella sonnei / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D022622:Shiga Toxin 1
keywords: California; County of San Diego; Escherichia coli; Mexico; STEC; San Joaquin County; Shiga toxin; Shigella; Stx-1 shigellosis; United States; antibiotic resistance; antimicrobial resistance; bacteria; cytotoxins; diarrhea; dysenteriae; enteric infections; flexneri; gastrointestinal; shigellemia; sonnei; travel