Survey, laboratory and statistical methods for the BSAC Resistance Surveillance Programmes.

Area of Science:

• Microbiology
• Infectious Diseases
• Public Health Surveillance

Background:

• Antimicrobial resistance (AMR) poses a significant global health threat.
• Effective surveillance is crucial for monitoring AMR trends and informing treatment guidelines.
• The British Society for Antimicrobial Chemotherapy (BSAC) established surveillance programmes for bloodstream and respiratory infections in the UK and Ireland.

Purpose of the Study:

• To describe in detail the methodologies employed by the BSAC Bacteraemia and Respiratory Resistance Surveillance Programmes.
• To outline the data collection, laboratory analysis, and statistical approaches used.
• To establish the foundation for interpreting long-term AMR trends presented in linked publications.

Main Methods:

• Sentinel laboratories across the UK and Ireland submitted bacterial isolates.
• Central laboratories confirmed identifications, performed MIC testing using BSAC agar dilution, and conducted further standard tests.
• MIC method variability was assessed; susceptibility classification used BSAC and EUCAST breakpoints; statistical analysis accounted for inter-centre variation.

Main Results:

• Over 16,000 respiratory and 15,000 bacteraemia isolates were collected between 1999-2007 and 2001-2006, respectively.
• Collecting laboratories' bacteraemia organism patterns generally aligned with national data.
• MIC measurements demonstrated high reproducibility (>90% agreement within +/-1 doubling dilution).

Conclusions:

• The BSAC surveillance programmes have successfully generated reliable antimicrobial susceptibility data in the UK and Ireland.
• These programmes provide a robust foundation for understanding AMR trends over multiple years.
• Detailed findings on non-susceptibility and predictive factors are available in linked papers.