3.3 Scale of resistance

Although we would not go back to life as it was in the 19th century if we lost antibiotics, we should definitely not underestimate the impact that losing them would have on global health.

In 2016, the UN assembly gathered to discuss the problem of AMR and called it one of the biggest threats to global health. This was only the fourth time in the history of the UN that a health topic was discussed at its General Assembly – the other three were HIV, noncommunicable diseases and Ebola (WHO, 2016).

Activity 15: Resistance of Acinetobacter baumannii to carbapenems

Now let’s look at the scale of resistance worldwide.

Acinetobacter baumannii is an opportunistic pathogen that can cause a range of diseases, including pneumonia and bloodstream infections. Carbapenems are a class of highly effective broad-spectrum antibiotics, usually reserved for treating multi-drug-resistant infections. The fact that this species has developed resistance to such an effective and important antibiotic class is particularly worrying.

In Figure 2 you see the resistance that Acinetobacter baumannii has developed against a class of antibiotic known as carbapenems as documented by the One Health Trust (OHT). The percentage of resistant isolates of Acinetobacter baumannii is indicated in blue; the darker the country, the higher the percentage of resistance. There are no data available on the countries in light grey.

Maximise

Figure 2 Resistance of Acinetobacter baumannii to carbapenems.

Is data available from your country?

Which countries have the highest level of resistant isolates of Acinetobacter baumannii against carbapenems?

Discussion

The darker blue the country, the higher the proportion of isolates that were found to be resistant. High levels of resistance are found in Mexico, Venezuela, Argentina, South Africa, Tunisia, Poland, Ukraine, Spain, Italy, Greece, Turkey, Saudi Arabia, Russia, China, India and Pakistan.

Let’s zoom in to a few countries to see the percentage of Acinetobacter baumannii isolates found to be resistant over time. Take a minute to look at the trends of resistance in Russia, the United States and Venezuela (Figures 3–5).

The figures show the percentage of Acinetobacter baumannii isolates resistant to carbapenems over time in Russia, Venezuela and the United States in different years as documented by the OHT. Data are based on different data sources.

Different colours on the graphs are assigned at random.

Figure 3 Antibiotic resistance of Acinetobacter baumannii in Russia. (Source: Central Asian and Eastern European Surveillance of Antimicrobial Resistance (CAESAR))

Figure 4 Antibiotic resistance of Acinetobacter baumannii in Venezuela. (Source: Venezuela: Programa Venezolano de Vigilancia de la Resistencia a los Antimicrobianos (PROVENRA))

Figure 5 Antibiotic resistance of Acinetobacter baumannii in the USA. (Source: United States: The Surveillance Network, USA/ResistanceMap Surveillance Network/National Healthcare Safety Network, USA)

What is the trend that you can identify on the percentage of Acinetobacter baumannii isolates resistant to carbapenems over time? What is different in the trend in the United States?

Discussion

In Russia and Venezuela, the level of resistance has increased over time. It is not increasing in a straight line, but the trend is going up. In the United States, the level of resistance increased until 2009 but started decreasing after that year.

Why are the timelines of the graphs different?

Discussion

The timelines of the graphs are different due to the practical reasons of the availability of information. In Section 5.3 you will learn about international efforts to standardise data collection on the levels of resistance of different pathogens all over the world.

Unfortunately, Acinetobacter baumannii is not the only type of bacterium that shows resistance to this class of antibiotics: several other types of bacteria have developed resistance to carbapenems or other broad-spectrum antibiotics such as cephalosporins and vancomycin. The WHO developed the priority pathogen list (see Table 1) for development of new antibiotics. This list (adapted from WHO, 2024) ranks antibiotic-resistant bacterial pathogens for which alternative treatments are urgently required, giving each a priority rating. As you can see, the priority rating for Acinetobacter baumannii is ‘critical’.

The WHO has also produced a list of priority pathogens for surveillance as part of its Global Antimicrobial Resistance Surveillance (GLASS) programme. This is a list of organisms in which high levels of resistance have been reported and are also some of the most common causes of bacterial infections. The priority pathogens for the GLASS surveillance (WHO, 2023) is now identical to the priority pathogens list shown in Table 1 with one exception: Mycobacterium tuberculosis is not included on the GLASS list.