Timely intervention and control of a novel coronavirus (COVID-19) outbreak at a large skilled nursing facility-San Francisco, California, 2020.

Objective: To describe epidemiologic and genomic characteristics of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in a large skilled-nursing facility (SNF), and the strategies that controlled transmission.

Design, Setting, And Participants: This cohort study was conducted during March 22-May 4, 2020, among all staff and residents at a 780-bed SNF in San Francisco, California.

Methods: Contact tracing and symptom screening guided targeted testing of staff and residents; respiratory specimens were also collected through serial point prevalence surveys (PPSs) in units with confirmed cases.

Importation and domestic transmission of Shigella sonnei resistant to ciprofloxacin - United States, May 2014-February 2015.

In December 2014, PulseNet, the national molecular subtyping network for foodborne disease, detected a multistate cluster of Shigella sonnei infections with an uncommon pulsed-field gel electrophoresis (PFGE) pattern. CDC's National Antimicrobial Resistance Monitoring System (NARMS) laboratory determined that isolates from this cluster were resistant to ciprofloxacin, the antimicrobial medication recommended to treat adults with shigellosis. To understand the scope of the outbreak and to try to identify its source, CDC and state and local health departments conducted epidemiologic and laboratory investigations.