Sources of antibiotic resistance: zoonotic, human, environment

Antibiotic resistance is a global problem that must be managed under the One Health perspective. Retrospectively, it is assumed that microbial populations able to cope with compounds with antimicrobial activity and susceptible bacteria lived in equilibrium for a thousand years. This situation would change in the middle 1940s of the twentieth century when one of the most important revolutions of modern medicine started - the use of a natural antimicrobial compound, the penicillin, to treat infectious bacterial diseases. Over the years, the massive use of antibiotics in human and animal medicine, as well as in animal production for both growth promotion and infection prophylaxis/metaphylaxis, accelerated and shaped one of the most successful evolutionary case studies. As a result of an impressive combination of genome and community dynamics, bacteria with acquired antibiotic resistance are nowadays widespread across different environmental compartments (water, soil, wildlife) as well as in the human food chain (poultry, livestock, aquaculture, produce). Hence, the evolutionary success of these bacteria turned to represent a major threat to the human health. This review discusses some of the drivers and paths of antibiotic resistance dissemination across zoonotic, human, and environmental sources.info:eu-repo/semantics/acceptedVersio

EFSA BIOHAZ Panel (EFSA Panel on Biologicial Hazards), 2013. Scientific Opinion on the public health hazards to be covered by inspection of meat (solipeds)

A risk ranking process identified Trichinella spp. as the most relevant biological hazard in the context of meat inspection of domestic solipeds. Without a full and reliable soliped traceability system, it is considered that either testing all slaughtered solipeds for Trichinella spp., or inactivation meat treatments (heat or irradiation) should be used to maintain the current level of safety. With regard to general aspects of current meat inspection practices, the use of manual techniques during current post-mortem soliped meat inspection may increase microbial cross-contamination, and is considered to have a detrimental effect on the microbiological status of soliped carcass meat. Therefore, the use of visual-only inspection is suggested for “non-suspect” solipeds. For chemical hazards, phenylbutazone and cadmium were ranked as being of high potential concern. Monitoring programmes for chemical hazards should be more flexible and based on the risk of occurrence, taking into account Food Chain Information (FCI), covering the specific on-farm environmental conditions and individual animal treatments, and the ranking of chemical substances, which should be regularly updated and include new hazards. Sampling, testing and intervention protocols for chemical hazards should be better integrated and should focus particularly on cadmium, phenylbutazone and priority “essential substances” approved for treatment of equine animals. Implementation and enforcement of a more robust and reliable identification system throughout the European Union is needed to improve traceability of domestic solipeds. Meat inspection is recognised as a valuable tool for surveillance and monitoring of animal health and welfare conditions. If visual only post-mortem inspection is implemented for routine slaughter, a reduction in the detection of strangles and mild cases of rhodococcosis would occur. However, this was considered unlikely to affect the overall surveillance of both diseases. Improvement of FCI and traceability were considered as not having a negative effect on animal health and welfare surveillance

N2 Gas Flushing Limits the Rise of Antibiotic-Resistant Bacteria in Bovine Raw Milk during Cold Storage

Antibiotic resistance has been noted to be a major and increasing human health issue. Cold storage of raw milk promotes the thriving of psychrotrophic/psychrotolerant bacteria, which are well known for their ability to produce enzymes that are frequently heat stable. However, these bacteria also carry antibiotic resistance (AR) features. In places, where no cold chain facilities are available and despite existing recommendations numerous adulterants, including antibiotics, are added to raw milk. Previously, N-2 gas flushing showed real potential for hindering bacterial growth in raw milk at a storage temperature ranging from 6 to 25 degrees C. Here, the ability of N-2 gas (N) to tackle antibiotic-resistant bacteria was tested and compared to that of the activated lactoperoxidase system (HT) for three raw milk samples that were stored at 6 degrees C for 7 days. To that end, the mesophiles and psychrotrophs that were resistant to gentamycin (G), ceftazidime (Ce), levofloxacin (L), and trimethoprim-sulfamethoxazole (TS) were enumerated. For the log(10) ratio (which is defined as the bacterial counts from a certain condition divided by the counts on the corresponding control), classical Analyses of Variance (ANOVA) was performed, followed by a mean comparison with the Ryan-Einot-Gabriel-Welsch multiple range test (REGWQ). If the storage "time" factor was the major determinant of the recorded effects, cold storage alone or in combination with HT or with N promoted a sample-dependent response in consideration of the AR levels. The efficiency of N in limiting the increase in AR was highest for fresh raw milk and was judged to be equivalent to that of HT for one sample and superior to that of HT for the two other samples; moreover, compared to HT, N seemed to favor a more diverse community at 6 degrees C that was less heavily loaded with antibiotic multi-resistance features. Our results imply that N-2 gas flushing could strengthen cold storage of raw milk by tackling the bacterial spoilage potential while simultaneously hindering the increase of bacteria carrying antibiotic resistance/multi-resistance features.Peer reviewe

ECDC/EFSA/EMA second joint report on the integrated analysis of the consumption of antimicrobial agents and occurrence of antimicrobial resistance in bacteria from humans and food‐producing animals

Abstract The second ECDC/EFSA/EMA joint report on the integrated analysis of antimicrobial consumption (AMC) and antimicrobial resistance (AMR) in bacteria from humans and food‐producing animals addressed data obtained by the Agencies’ EU‐wide surveillance networks for 2013–2015. AMC in both sectors, expressed in mg/kg of estimated biomass, were compared at country and European level. Substantial variations between countries were observed in both sectors. Estimated data on AMC for pigs and poultry were used for the first time. Univariate and multivariate analyses were applied to study associations between AMC and AMR. In 2014, the average AMC was higher in animals (152 mg/kg) than in humans (124 mg/kg), but the opposite applied to the median AMC (67 and 118 mg/kg, respectively). In 18 of 28 countries, AMC was lower in animals than in humans. Univariate analysis showed statistically‐significant (p < 0.05) associations between AMC and AMR for fluoroquinolones and Escherichia coli in both sectors, for 3rd‐ and 4th‐generation cephalosporins and E. coli in humans, and tetracyclines and polymyxins and E. coli in animals. In humans, there was a statistically‐significant association between AMC and AMR for carbapenems and polymyxins in Klebsiella pneumoniae. Consumption of macrolides in animals was significantly associated with macrolide resistance in Campylobacter coli in animals and humans. Multivariate analyses provided a unique approach to assess the contributions of AMC in humans and animals and AMR in bacteria from animals to AMR in bacteria from humans. Multivariate analyses demonstrated that 3rd‐ and 4th‐generation cephalosporin and fluoroquinolone resistance in E. coli from humans was associated with corresponding AMC in humans, whereas resistance to fluoroquinolones in Salmonella spp. and Campylobacter spp. from humans was related to consumption of fluoroquinolones in animals. These results suggest that from a ‘One‐health’ perspective, there is potential in both sectors to further develop prudent use of antimicrobials and thereby reduce AMR

Antimicrobial consumption and resistance in bacteria from humans and food‐producing animals

Abstract The fourth joint inter‐agency report on integrated analysis of antimicrobial consumption (AMC) and the occurrence of antimicrobial resistance (AMR) in bacteria from humans and food‐producing animals (JIACRA) addressed data obtained by the Agencies' EU‐wide surveillance networks for 2019–2021. The analysis also sought to identify whether significant trends in AMR and AMC were concomitant over 2014–2021. AMC in both human and animal sectors, expressed in mg/kg of estimated biomass, was compared at country and European level. In 2021, the total AMC was assessed at 125.0 mg/kg of biomass for humans (28 EU/EEA countries, range 44.3–160.1) and 92.6 mg/kg of biomass for food‐producing animals (29 EU/EEA countries, range 2.5–296.5). Between 2014 and 2021, total AMC in food‐producing animals decreased by 44%, while in humans, it remained relatively stable. Univariate and multivariate analyses were performed to study associations between AMC and AMR for selected combinations of bacteria and antimicrobials. Positive associations between consumption of certain antimicrobials and resistance to those substances in bacteria from both humans and food‐producing animals were observed. For certain combinations of bacteria and antimicrobials, AMR in bacteria from humans was associated with AMR in bacteria from food‐producing animals which, in turn, was related to AMC in animals. The relative strength of these associations differed markedly between antimicrobial class, microorganism and sector. For certain antimicrobials, statistically significant decreasing trends in AMC and AMR were concomitant for food‐producing animals and humans in several countries over 2014‐2021. Similarly, a proportion of countries that significantly reduced total AMC also registered increasing susceptibility to antimicrobials in indicator E. coli from food‐producing animals and E. coli originating from human invasive infections (i.e., exhibited ‘complete susceptibility’ or ‘zero resistance’ to a harmonised set of antimicrobials). Overall, the findings suggest that measures implemented to reduce AMC in food‐producing animals and in humans have been effective in many countries. Nevertheless, these measures need to be reinforced so that reductions in AMC are retained and further continued, where necessary. This also highlights the importance of measures that promote human and animal health, such as vaccination and better hygiene, thereby reducing the need for use of antimicrobials