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World Antimicrobial Awareness Week 2022

Preventing Antimicrobial Resistance Together

World Antimicrobial Awareness Week (WAAW) is a global campaign led by the World Health Organization that is celebrated annually to improve awareness and understanding of antimicrobial resistance (AMR) and encourage best practices among the public, One Health stakeholders, and policymakers, who all play a critical role in reducing the further emergence and spread of AMR.

The Go-To Source for AST Methods and Interpretive Criteria

CLSI has a longstanding reputation for its diligent development of microbiology and antimicrobial susceptibility testing (AST) standards and guidelines on test methods and QC procedures. CLSI annually creates and revises AST breakpoints to meet global public health challenges related to antimicrobial resistance. CLSI is proud to support WAAW by contributing to this year’s theme, “Preventing Antimicrobial Resistance Together.”

Learn From CLSI Volunteers

AST and Antimicrobial Stewardship for the Veterinary Profession

Learn about how CLSI's VET09—Understanding Susceptibility Test Data as a Component of Antimicrobial Stewardship in Veterinary Settings, can help veterinarians optimize their use of AST and make informed decisions about when AST can guide therapy and when AST is not warranted by reading a guest blog post by Virginia R. Fajt, DVM, PhD, DACVCP, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, USA.

AST News Update Archives

The CLSI AST Outreach Working Group is part of the CLSI Subcommittee on AST. The working group works to efficiently convey information regarding contemporary AST practices, recommendations, and resources to the clinical microbiology community. They oversee a bi-annual news letter, you can view all past editions on our website—including versions translated into Spanish and Chinese.

Our Subcommittees: Get Involved

CLSI has subcommittees that are responsible for areas related to AMR. They write draft documents, evaluate and respond to comments on content throughout the document development process, conduct scheduled document reviews, and may be responsible for continual revision of certain documents. Learn more about each below!

Antimicrobial Susceptibility Testing (AST) Subcommittee

The AST Subcommittee provides useful information to laboratories, enabling them to advise clinicians in the selection of appropriate antimicrobial therapy.

Antifungal Susceptibility Testing Subcommittee

The Antifungal Subcommittee collaborates to develop standards and guidelines that promote accurate antifungal susceptibility testing and appropriate reporting.

Veterinary Antimicrobial Susceptibility Testing (VAST)

The VAST Subcommittee collaborates to develop standards and guidelines that promote accurate antimicrobial susceptibility testing and appropriate reporting.

Featured CLSI Products | View our products that support preventing antimicrobial resistance.

CLSI Free M100 and M27M44S

Performance Standards for Antimicrobial & Antifungal Susceptibility Testing

Access read-only web versions of M100 and M27M44S for free and quickly reference the most trusted AST and antifungal breakpoints. Available online as a convenient companion to our M100 document and M27M44S document.

CLSI Using M100-Ed32

Using M100: Performance Standards for Antimicrobial Susceptibility Testing

Improve your lab's antimicrobial susceptibility testing (AST) by using this self-paced, online learning program. This interactive program will teach you how to navigate the many tables found in CLSI's document M100.


Breakpoints in Use

CLSI's Outreach Working Group has developed this free, optional spreadsheet that laboratories can use to record breakpoints in use.


Development of In Vitro Susceptibility Testing Criteria and Quality Control Parameters, 5th Edition

This guideline discusses the necessary and recommended data for selecting appropriate breakpoints and quality control ranges for antimicrobial agents.


Understanding Susceptibility Test Data as a Component of Antimicrobial Stewardship in Veterinary Settings, 1st Edition

This report provides veterinarians with the information needed to successfully acquire and interpret antimicrobial susceptibility test results. It promotes common understanding between the veterinarian and the veterinary microbiology laboratory by providing example culture and susceptibility reports and animal species-specific guidance on applying breakpoints to interpret susceptibility test results.

CLSI On-Demand CLSI and CAP Webinar 2022

Breakpoints Matter: Understanding CLSI Efforts and New CAP Requirements to Ensure Appropriate Antimicrobial Treatment for all Patients