The use of antibiotics in the food industry is a less-recognized, but rapidly emerging cause of global antibiotic resistance.
About 80% of use of medically important antibiotics occurs in the animal sector in some countries, primarily to enhance growth in healthy animals. They are used in food-producing animals to treat and control bacterial infections in the presence of disease (therapeutic use), and for disease prevention (prophylactic use) and growth promotion (subtherapeutic use) in the absence of disease.
The widespread misuse and indiscriminate use of antibiotics in agriculture is a major contributor to antibiotic resistance in humans. Development of antibiotic-resistant bacteria in food-producing animals, which can then be transmitted to humans via food and other transmission routes.
Some of the antibiotics that are used in animals are usually the last line of treatment for critical infections in humans or are one among the very limited number of treatment options available for serious infections in humans.
According to the World Health Organization (WHO), “Antimicrobial use in food-producing animals can lead to selection and dissemination of antimicrobial-resistant bacteria in food-producing animals, which can then be transmitted to humans via food and other transmission routes.”
The WHO published new guidelines last year on the use of medically important antibiotics in food-producing animals and has recommended that farmers and the food industry stop using antibiotics routinely to promote growth and prevent disease in healthy animals.
The new WHO guidelines call for the following actions regarding the use of medically important antibiotics in animals:
- Overall reduction in use of all classes of medically important antimicrobials in food-producing animals
- Complete restriction of all classes of medically important antimicrobials for purposes of growth promotion in food-producing animals
- Complete restriction for prevention of infectious diseases in healthy animals that have not yet been clinically diagnosed unless animals in close vicinity have been diagnosed with a disease that requires such use
- Medically important antimicrobials should not be used to either to treat or control dissemination of a clinically diagnosed infectious disease identified within a group of food-producing animals
- Testing of sick animals, when possible, to determine the most appropriate antibiotic for their infection
- Selection of antibiotics from the WHO list of those that are considered “least important to human health” and avoidance of those considered “highest priority, critically important”
- Additional recommendations include vaccination of animals to reduce the need for antibiotics, as well as improved production, processing, and hygiene practices.
There is also increasing attention toward the identification and development of alternatives to antibiotics for use in animals.
- Vaccines that could reduce the use of medically important antibiotics
- Microbial-derived products, such as probiotics and bacteriophage gene products
- Non-nutritive phytochemicals, including prebiotics
- Immune-related products, such as antibodies, microbial peptides, and cytokines
- Chemicals, including enzymes
- Regulatory pathways to enable the licensure of alternatives to antibiotics