130 - Increase in Multidrug Resistance (2011–2018) and the Emergence of Extensive Drug Resistance (2020) in Shigella sonnei in the United States

Background: Multidrug-resistant (MDR) Shigella sonnei infections are a serious public health threat, and outbreaks are common among men who have sex with men (MSM). In February 2020, Australia’s Department of Health notified CDC of extensively drug-resistant (XDR) S. sonnei in 2 Australian residents linked to a cruise that departed from Florida. We describe an international outbreak of XDR S. sonnei and report on trends in MDR among S. sonnei in the United States.

Methods: Health departments (HDs) submit every 20th Shigella isolate to CDC’s National Antimicrobial Resistance Monitoring System (NARMS) laboratory for susceptibility testing. We defined MDR as decreased susceptibility to azithromycin (MIC ≥32 µg/mL) with resistance to ampicillin, ciprofloxacin, and cotrimoxazole, and XDR as MDR with additional resistance to ceftriaxone. We used PulseNet, the national subtyping network for enteric disease surveillance, to identify US isolates related to the Australian XDR isolates by short-read whole genome sequencing. We screened these isolates for resistance determinants (ResFinder v3.0) and plasmid replicons (PlasmidFinder) and obtained patient histories from HDs. We used long-read sequencing to generate closed plasmid sequences for 2 XDR isolates.

Results: NARMS tested 2,781 S. sonnei surveillance isolates during 2011–2018; 80 (2.9%) were MDR, including 1 (0.04%) that was XDR. MDR isolates were from men (87%), women (9%), and children (4%). MDR increased from 0% in 2011 to 15.3% in 2018 (Figure). In 2020, we identified XDR isolates from 3 US residents on the same cruise as the Australians. The US residents were 41–42 year-old men; 2 with available information were MSM.  The US and Australian isolates were highly related (0–1 alleles).  Short-read sequence data from all 3 US isolates mapped to the bla_CTX-M-27 harboring IncFII plasmids from the 2 Australian isolates with >99% nucleotide identity.  bla_CTX-M-27 genes confer ceftriaxone resistance.Increase in Percentage of Shigella sonnei Isolates with Multidrug Resistance* in the United States, 2011–2018†


Conclusion: MDR S. sonnei is increasing and is most often identified among men. XDR S. sonnei infections are emerging and are resistant to all recommended antibiotics, making them difficult to treat without IV antibiotics. This outbreak illustrates the alarming capacity for XDR S. sonnei to disseminate globally among at-risk populations, such as MSM.

Presenting Author(s)

• 

  Naeemah Z. Logan, MD

  Medical Epidemiologist
  Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA
  Atlanta, GA

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.

  Slides Slides and Audio

Co-Author(s)

• BK

  Beth E. Karp, DVM, MPH

  Veterinary Epidemiologist
  Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• KT

  Kaitlin A. Tagg, PhD

  Microbiologist
  Centers for Disease Control and Prevention
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• CB

  Claire Burns-Lynch, MPH

  Fellow
  Emory University Rollins School of Public Health
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• JC

  Jessica Chen, PhD

  Scientist
  Centers for Disease Control and Prevention
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• AG

  Amanda Garcia-Williams, PhD

  Behavioral Scientist
  Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• ZM

  Zachary A. Marsh, MPH

  Epidemiologist
  Centers for Disease Control and Prevention
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• KO

  Kevin O'Laughlin, MD

  EIS officer
  Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• 

  Ian D. Plumb, MBBS, MSc

  Medical Epidemiologist
  Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• MS

  Morgan N. Schroeder, MPH

  PulseNet Escherichia Database Coordinator
  Centers for Disease Control and Prevention
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• HW

  Hattie E. Webb, PhD

  Microbiologist
  Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• HZ

  Hannah Zenas, MPH

  ORISE Fellow
  Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• JD

  Jenny Draper, PhD

  Bioinformatician
  (2) Microbial Genomics Reference Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, ICPMR Westmead, NSW Australia (3) University of Sydney, Sydney, NSW Australia
  Westmead, New South Wales, Australia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• AG

  Andrew Ginn, PhD

  Senior Hospital Scientist
  (2) Microbial Genomics Reference Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, ICPMR Westmead, NSW Australia (3) University of Sydney, Sydney, NSW Australia
  Westmead, New South Wales, Australia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• EM

  Elena Martinez, PhD

  Bioinformatician
  (2) Microbial Genomics Reference Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, ICPMR Westmead, NSW Australia (3) University of Sydney, Sydney, NSW Australia
  Westmead, New South Wales, Australia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• SP

  Sally R. Partridge, PhD

  Associate Professor
  (3) University of Sydney, Sydney, NSW Australia (4) Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, Westmead Hospital, NSW Australia
  Westmead, New South Wales, Australia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• ES

  Eby Sim, PhD

  Hospital Scientist
  (2) Microbial Genomics Reference Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, ICPMR Westmead, NSW Australia (3) University of Sydney, Sydney, NSW Australia
  Westmead, New South Wales, Australia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• VS

  Vitali Sintchenko, MBBS, PhD

  Professor
  (2) Microbial Genomics Reference Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, ICPMR Westmead, NSW Australia (3) University of Sydney, Sydney, NSW Australia
  Westmead, New South Wales, Australia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• JI

  Jonathan Iredell, MBBS, PhD

  Director, Centre for Infectious Diseases and Microbiology
  (2) Microbial Genomics Reference Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, ICPMR Westmead, NSW Australia (3) University of Sydney, Sydney, NSW Australia (4) Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, Westmead Hospital, NSW Australia
  Westmead, New South Wales, Australia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
• 

  Louise Francois Watkins, MD, MPH

  Medical Officer
  Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention
  Atlanta, Georgia

  Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.