4.1 Recap: measuring AMR

In the module Fundamentals of data for AMR, you learned that AMR is generally measured using the following three indicators:

• Proportion of specimens where a target pathogen was isolated: This relates to the frequency with which pathogens are isolated from human or animal specimens. When sampling healthy food animals, for example, not all animals will have the target pathogen of interest (such as Salmonella spp.).
• Proportion of isolates that were resistant to each antimicrobial: This is a commonly used indicator in human and animal AMR surveillance.
• Distribution of minimum inhibitory concentration (MIC): Results from broth/agar dilution testing are often presented as distributions of MICs for particular isolates and antimicrobials.

Assuming high quality data collection, these indicators meet most of the key principles of best practice listed above with the exception of generating direct benefits to those who provide or collect data (Table 2). For example, if the proportion of isolates resistant to each antimicrobial is only summarised at national level, and this data is only reported several months after it was originally collected, this may not be very helpful for clinicians to understand the best way to prevent or treat resistant infections in their patients. When designing AMR surveillance systems, particular emphasis should be given to the data providers’ needs and perceptions to ensure long-term submission of quality data.