EFSA evaluates the public health risk of bacterial strains resistant to certain antimicrobials in food and food-producing animals

Antimicrobials are used in human and veterinary medicine to treat infections caused by bacteria.

Resistance to antimicrobials occurs when bacteria develop mechanisms that reduce their effectiveness or render their use ineffective. Resistant bacteria can spread through many routes. When antimicrobial resistance occurs in zoonotic bacteria [2] present in animals and food, it can also compromise the effective treatment of certain infectious diseases in humans.

In its assessment, the BIOHAZ Panel evaluated the risks to public health of bacterial strains producing two types of enzymes; extended-spectrum beta-lactamases (ESBL) and AmpC beta-lactamases (AmpC). These enzymes inactivate the effects of antimicrobials such as penicillins and cephalosporins which are defined as critically important antimicrobials for both human and veterinary medicine[3].
EFSA’s Panel experts conclude that different bacteria are able to produce these enzymes, most often Escherichia coli (E. coli) and Salmonella[4]. Since 2000, ESBL/AmpC-producing Salmonella and E. coli in animals and foods have been increasingly reported both in Europe and globally. These resistant bacterial strains have been found in all major food-producing animals, most frequently in live chickens and chicken meat, eggs and other poultry products. In addition to identifying the relevant bacterial strains, the opinion also looked at epidemiology of resistance caused by ESBL/AmpC enzymes and the methods for detection of this type of resistance.
The BIOHAZ Panel analyzed the risk factors contributing to the occurrence, emergence and spread of ESBL/AmpC-producing bacteria and concluded that the use of antimicrobials in general (and not only that related to cephalosporins) is a risk factor for the spread of these types of resistant bacterial strains. The experts concluded that decreasing the overall use of antimicrobials in food-producing animals should be of high priority in the EU as these bacterial strains are often resistant to many other commonly used veterinary drugs. It was also concluded that an additional risk factor is the extensive trade of animals in EU Member States.
When evaluating possible control options, EFSA’s scientists state amongst other recommendations that a highly effective control option to reduce ESBL/AmpC-producing bacteria in food-producing animals at the EU-level would be to restrict or stop the use of cephalosporins in the treatment of food-producing animals.

The Panel also recommended improvements for the ongoing EU surveillance and monitoring programs on antimicrobial resistance caused by ESBL/AmpC enzymes.

Source: Scientific Opinion on the public health risks of bacterial strains producing extended-spectrum β-lactamases and/or AmpC β-lactamases in food and food-producing animals