AWaRe classification of antibiotics

As we discussed in the previous step, collecting data (surveillance) about antimicrobial consumption and quality of use is essential to AMS programmes (ASPs). To collect data, it is important to know:

• the verified method of carrying out these measurements, e.g. point prevalence survey (we will discuss this further in week 3).
• the human resources and skills required.
• the need for governance of data/information.
• how it will be analysed and communicated.

Over the years, it has been seen that many low and middle-income countries are faced with challenges that high-income countries deal with less. Examples of such challenges are poor quality of antibiotics, loosely regulated over the counter sales and limited access to essential antibiotics. This problem needed addressing to support the effective treatment of infections.

Therefore, the WHO, in 2017, updated the Essential Medicines List (EML), a register of minimum medicine needs for every healthcare system, and proposed a novel metric for antimicrobial use: the AWaRe index. This index classified over 240 antimicrobials available worldwide into three groups to balance excess use of antibiotics with access restrictions. It is a useful tool for monitoring antibiotic consumption, defining targets and monitoring the effects of stewardship policies that aim to optimise antibiotic use and curb antimicrobial resistance.

Ensuring an understanding and incorporation of the AWaRe categorisation into the hospitals antimicrobial guidelines/ policy is important to support rational antimicrobial use.

In 2022, the WHO released a new document – the WHO AWare (Access, Watch, Reserve) antibiotic book.

The three groups are described below:

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Access

Access antibiotics have a narrow spectrum of activity, lower cost, a good safety profile and generally low resistance potential. They are recommended as empiric first- or second-choice treatment options for common infections.

Due to these antibiotics showing a lower resistance potential in comparison to the other AWaRe categories and being able to act on a broad range of community encountered pathogens, they should be widely available, affordable and of the highest quality to ensure appropriate use and access.

Watch

Watch antibiotics are broader-spectrum antibiotics, generally with higher costs and are recommended only as first-choice options for patients with more severe clinical presentations or for infections where the causative pathogens are more likely to be resistant to Access antibiotics (e.g. upper urinary tract infections).

They are used as first- or second-line options for only a limited number of indications. They need to be monitored and prioritised as targets for stewardship programmes.

Reserve

Reserve antibiotics are last-choice antibiotics used to treat multidrug-resistant infections. These antibiotics will need intense monitoring. These antibiotics should only be used under specific conditions to conserve their effectiveness. The reserve group antibiotics should be tailored to highly specific patients and settings and used only on multidrug-resistant organisms when all alternatives have failed or are no longer suitable. These antibiotics must be highly protected and prioritised as key targets of national and international stewardship programmes, with their utilisation and usage monitored to preserve their effectiveness.

Estimating the use of antibiotics within each group at national and hospital levels regularly will help optimise antibiotic use and help define goals for future quality improvement.

Globalisation of AWaRe

The AWaRe classification has been used in many countries and hospitals worldwide, promoting rational usage of antibiotics whilst improving access to essential medicines. A good example of this classification is a study to analyse paediatric prescribing data across 56 countries. In the point prevalence survey, there was a relatively high use of reserve antibiotics in Mexico, which may suggest either higher rates of infections due to multi-drug resistance pathogens or misuse of these agents for infections that could be treated with Access or Watch group antibiotics.

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This and other studies can show patterns of antibiotic prescription in various countries. For example, higher usage of Watch antibiotics has been observed in many lower and upper-middle-income countries compared with high-income countries. The reasons for this are multi-factorial but the data provided by using the WHO AWaRe classification can support local and national AMS activities.

The AWaRe classification can be used at a country level for AMS and for “benchmarking” purposes between different countries. Therefore, using the AWaRe classification with antibiotic policies and guidelines and applying this classification for monitoring AMS activities is strongly encouraged. The image below shows how AWaRe can be adapted for local use.

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WHO aims to use the AWaRe classification to support the monitoring of antibiotic prescribing and inform AMS programmes. They have proposed a new target stating that by 2023 at least 60% of national antibiotic consumption should come from the Access group.

Overall, translating antibiotic usage data into the AWaRe categories will provide valuable insights into how antibiotics are prescribed globally, potentially becoming an essential stewardship tool.

In 2022 developed the “The WHO Essential Medicines List Antibiotic Book”, which provides more detail on the Essential Medicines List. You can see the draft of the e-book here.

Now over to you – have a go at answering these questions, and share your answers in the comments below:

1. Which countries do you identify with potentially significant inappropriate prescribing problems? Why do you think this may be? Refer back to the data above from the 2019 paediatric study to help you answer these questions.
2. What are your views on using Access, Watch and Reserve antibiotics in your own hospitals?