Drivers of AMR

The video above is from a presentation Nick Brown gave at the BSAC Spring conference 2021, outlining some of the findings of the “To Dip or Not To Dip” project. This is an example of a driver of resistance and the talk outlines how this project helps reduce prescribing.

In step 3.2 we learned that antimicrobial resistance mechanisms can occur naturally as part of the natural defences of microorganisms, especially with most antimicrobial agents being naturally produced. Here, we look at some factors which encourage the spread of resistance, driving a global increase in antimicrobial resistance.

Though resistance is a natural phenomenon, evidence exists for the role of human, animal and agricultural antimicrobial uses as the main drivers of AMR.

Antimicrobial use, misuse and overuse

Use of antimicrobial agents in human medicine exerts selective pressure through increased exposure to the agents prescribed; depending on the agents used, microorganisms with the right AMR mechanisms are thus selected for as they can survive antimicrobial courses and reproduce.

If you require a text version of the above image, this is available as a PDF

Rapid uptake in anti-infective usage is driven by both patient volume and resistance

Such use may not always be appropriate, with broad-spectrum agents often started empirically for cases of suspected infections that may not be supported by the final diagnosis following further laboratory investigations.

Additionally, antimicrobial use, misuse and overuse is also seen in veterinary and agricultural settings, with various studies in scientific literature attributing AMR, in part, to these areas (outside of use in human medicine).

Inadequate infection prevention and control (IPC)

Inadequate IPC strategies are key in spreading resistant microorganisms, especially in healthcare settings where the rise of healthcare-associated infections (HAIs) exemplifies the consequences associated with poor IPC practices. This WHO infographic summarises the role of IPC in preventing antibiotic resistance in healthcare, and can be applied for other antimicrobials.

General IPC guidelines advocate:

• Wearing appropriate personal protective equipment (PPE)

• Hand hygiene at the appropriate moments, including between patients and other tasks, after using the bathroom, before eating or touching (staff or patient) food, and after sneezing or coughing

• Regular cleaning of surfaces

• Never re-using needles or syringes

In areas of the world where access to clean water is limited, and other areas of sanitation are also inadequate, adhering to the above guidelines is more challenging and microorganisms (resistant or not) have more opportunities to spread between patients and to the environment.

Addressing such issues of antimicrobial use and infection prevention and control present important areas in slowing antimicrobial resistance, and will be further explored in Week 4.