Antimicrobial resistance remains commonly detected in bacteria in humans, animals and food: EFSA -ECDC report

Bacteria most frequently causing food-borne infections, such as Salmonella and Campylobacter, show significant resistance to common antimicrobials, according to the EFSA-ECDC European Union Summary Report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2012. Data show that combined resistance (co-resistance) to critically important antimicrobials remains low. While this means that treatment options for serious infections with these zoonotic bacteria are available in most cases, the fact that antimicrobial resistance was commonly detected is cause for concern.

If bacteria become clinically resistant to several antimicrobials (multidrug-resistant), treating the infections they cause can become more difficult or even impossible. In addition, the development of antimicrobial resistance (AMR) in bacteria in animals and food can also compromise the effective treatment of human infections, as resistant bacteria and resistance genes may be transferred to humans from animals and food. “That’s why a prudent use of antibiotics is crucial, not only in humans, but also in animals”, warned Marta Hugas, Acting Head of EFSA’s Risk Assessment and Scientific Assistance Department.

“In humans, the levels of clinical resistance to antimicrobials showed a great variability across the Member States, partly due to the use of different methods and criteria for interpreting data across the EU. In 2014, ECDC is launching the EU protocol for harmonised monitoring of antimicrobial resistance in human isolates of Salmonella and Campylobacter. Thus, we expect to get more accurate data from countries and as a result better comparability of data” said Johan Giesecke, Chief Scientist at ECDC.

Key findings

The joint report shows that clinical resistance in humans to commonly used antimicrobials in Salmonella spp. isolates was frequently detected at the EU level, with almost half of the isolates being resistant to at least one antimicrobial, and 28.9% of isolates being multidrug-resistant. However, levels of clinical resistance and co-resistance in Salmonella spp. isolates to critically important antimicrobials were low (0.2% co-resistance across the 12 Member States that submitted data).

Microbiological resistance in animals to commonly used antimicrobials in Salmonella spp. isolates was frequently detected in the animal species monitored, especially in broilers, pigs and turkeys. Microbiological resistance to ciprofloxacin (a critically important antimicrobial), was frequently observed in broilers and turkeys. Co-resistance to the critically important antimicrobials, ciprofloxacin and cefotaxime, was either not detected or reported at very low levels in reporting Member States¹.

In Campylobacter spp. isolates from human cases, clinical resistance to common antimicrobials was frequently detected. Very high proportions of isolates (47.4% EU average) were resistant to the critically important antimicrobial ciprofloxacin with increasing trends observed in several Member States.

Microbiological resistance to commonly used antimicrobials in Campylobacter spp. isolates was frequently detected in broilers. Co-resistance to critically important antimicrobials, ciprofloxacin and erythromycin, in C. jejuni in broilers was either not detected or reported at low levels.

Microbiological resistance to commonly used antimicrobials in E. coli isolates was frequently reported in broilers and pigs. Co-resistance to critically important antimicrobials in these animal species was mostly not detected or recorded at very low levels among the reporting Member States.

EFSA and ECDC monitor AMR in humans, animals and food. This is a pre-requisite to understanding how AMR develops and spreads. In its 2011 action plan against the rising threats from AMR, the European Commission identified key priority areas, including improved monitoring of antimicrobial resistance, to which this joint report makes an important contribution.

• The European Union Summary Report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2012