A new EFSA external scientific report, the CarbaCamp project, has found that no clear genetic determinants explain the observed carbapenem susceptibility patterns in Campylobacter coli and Campylobacter jejuni from animal, food and human sources, and recommends imipenem as the most suitable carbapenem for interim monitoring. The study, published on 10 July 2026, tested 1,889 isolates from 16 European countries using disc diffusion, with 596 isolates undergoing whole genome sequencing. The report follows an earlier EFSA recommendation from 2021 to include ertapenem in resistance monitoring of Campylobacter, prompted by emerging evidence of carbapenem non-susceptibility. The CarbaCamp project was designed to investigate carbapenem susceptibility in Campylobacter populations from food animal surveillance and human clinical contexts. The study found that ertapenem and meropenem showed bimodal distributions in disc diffusion and minimum inhibitory concentration tests, preventing the establishment of epidemiological cut-off values (ECOFFs). In contrast, imipenem exhibited a narrow, unimodal distribution, allowing tentative ECOFFs to be set at 35 mm for disc diffusion and 0.25 mg/L for MIC. No systematic differences were observed between EUCAST and CLSI broth microdilution methods. The report concludes that no definitive recommendation on which carbapenem to use for monitoring can be given due to unresolved issues with ertapenem and meropenem data, but imipenem appears most suitable for interim monitoring.
The findings impact EU regulatory bodies, which may need to update monitoring guidelines; national authorities, who rely on clear ECOFFs for surveillance; the food animal industry, particularly poultry, pig, and cattle sectors, which may face increased scrutiny; and public health authorities, who need reliable data on antimicrobial resistance trends.