Resistance to commonly used antimicrobials, such as ampicillin, tetracyclines, and sulfonamides, remains “persistently high” in both humans and animals for key pathogens, including Salmonella and Campylobacter, according to recent surveillance data from EU agencies.

A joint report by the European Food Safety Authority (EFSA) and the European Centre for Disease Prevention and Control (ECDC) also found that resistance to E. coli is frequently observed in animals, although resistance to Salmonella in laying hens is low.

“A comprehensive One-Health approach is essential to tackling AMR [Antimicrobial Resistance]. Robust surveillance systems, prudent antimicrobial use, and cross-sector collaboration are critical to mitigate the risk posed by antibiotic-resistant bacteria that can spread between animals and humans,” say Carlos Das Neves, chief scientist at EFSA, and Piotr Kramarz, chief scientist at ECDC.

The document reveals that high resistance to ciprofloxacin, a “critically important” fluoroquinolone antimicrobial for treating Salmonella and Campylobacter infections, is “a growing concern.”

Salmonella Enteritidis and Campylobacter jejuni from humans in over half of the European countries that submitted data were found to be increasing in resistance to ciprofloxacin. 

High to extremely high proportions of ciprofloxacin resistance have been observed in Campylobacter from food-producing animals and in Salmonella and E. coli from poultry specifically. 

Concerning bacteria trends 

The agencies say these trends are worrying as the 2024 World Health Organization list of harmful bacteria classifies fluoroquinolone-resistant non-typhoidal Salmonella (Salmonella serotypes that do not cause typhoid fever) as a high priority.

In contrast, resistance to other critically important antimicrobials used in human medicine remains uncommon for Salmonella and Campylobacter, for both humans and food-producing animals.

Although carbapenem resistance remains rare, the report warns that the occasional detection of carbapenem-resistant E. coli in food and animals requires sustained vigilance and further epidemiological investigations. 

Carbapenem-resistant Enterobacterales bacteria are recognized as a critical threat to public health. In 2025, EFSA will publish the first in a series of opinions on the current status of the occurrence and spread of carbapenemase-producing Enterobacterales in the food chain in the EU, EEA, and Switzerland to mitigate the risk. 

Despite the concerns, there were also positive trends, with data revealing significant progress in reducing resistance levels in several reporting countries. Nearly half of the European countries that submitted data indicated a decline in Campylobacter’s resistance to macrolide antibiotics in human cases of both C. jejuni and C. coli. 

Furthermore, resistance of Salmonella Typhimurium isolates from humans to penicillins and tetracyclines has decreased over time. The significant increasing trends for complete susceptibility of E. coli, as well as the significant decrease in the prevalence of ESBL-/AmpC-producing E. coli show that there has been encouraging progress in reducing AMR in food-producing animals in several EU member states over the last ten years, the report notes. 

Despite these improvements, the EFSA and ECDC stress antimicrobial resistance remains a significant public health threat that requires coordinated action with a “One-Health approach.” 

“Key measures include promoting the responsible use of antimicrobials, improving infection prevention and control, investing in research for new treatments, and implementing strong national policies to combat resistance effectively,” add the organizations.