Innovate4Health Food Systems Pillar: Reducing the need to use antimicrobials in food systems​


Infectious diseases importantly affect agricultural productivity and may through zoonotic disease transmission affect human health. In particular, antimicrobial medicines play an important role in treating disease not only in human medicine, but also in animal health. According to the sixth Annual Report on Antimicrobial Agents Intended for Use in Animals, the World Organisation for Animal Health estimated that 76,704 tonnes of antimicrobials were used in animals in 2018. In fact, nearly three-quarters (73%) of all antimicrobials sold globally were intended for use in food animal production. Antimicrobials, especially antifungal drugs, are also used in crop production. In South East Asia, almost 10% of plant protection recommendations issued for growing rice included antibiotics. It was estimated that in South East Asia alone, 63 tons of streptomycin were used each year for rice cultivation. In 2017, an estimated 10,259 tons of antibiotics were used in aquaculture, and this was projected to increase by over 30% in 2030.

Why should this use of antimicrobials in agri-food systems matter? Several key classes of antimicrobials are used not only in agriculture, but also in clinical practice to treat human patients. This makes the drug resistance that develops from their use in food systems also a risk when these microbes become transmitted to human populations. With 600 million cases of foodborne illness each year and nearly 420,000 deaths resulting, pathogens carrying such drug resistance can cross over from the food system into human medicine. While many of these infections are enteric, or affect the gastrointestinal tract, foodborne pathogens also can cause extra-intestinal infections. A form of E. coli urinary tract infections afflicting patients traced to retail poultry meat. Another example was the emergence of plasmid-mediated, colistin resistance. Colistin is an antibiotic seldom used in human medicine because of its side effects, except as a last-resort in the setting of multi-drug resistant infections, but its use in food animal production has now jeopardized its continued value to save lives.

The intensification of animal production has contributed to greater use of antimicrobials. Antimicrobials serve an important therapeutic role to ensure the health and welfare of animals as well as food security and safety. However, their overuse puts at risk their future value of these benefits and can negatively affect agricultural productivity. The risk flows not only from the levels of antimicrobials and drug-resistant pathogens in food products, but also in the waste stream from livestock, where 75 to 90 percent of the antimicrobials applied may be excreted.

The use of antimicrobials in the absence of diagnosed disease or routinely to prevent or treat disease has contributed to antimicrobial resistance (AMR). In 2017, the World Health Organization made several key recommendations on the use of medically important antimicrobials in food-producing animals. Among these, they called for “an overall reduction in the use of all classes of medically important antimicrobials in food-producing animals” and a “complete restriction of use of all classes of medically important antimicrobials in food-producing animals for growth promotion” and “for prevention of infectious diseases that have not yet been clinically diagnosed.” Yet forty countries, or a quarter of those in the sixth World Organisation for Animal Health survey, still reported that antimicrobials were used for growth promotion.

The use of antimicrobials in food animals may generally occur with or without veterinary or laboratory diagnosis. In case of use with diagnosis, antimicrobials may either be used for purposes of treatment of a specific, diagnosed condition, or for metaphylaxis, the administration of antimicrobials to a group of animals perceived to be at immediate threat of a diagnosed disease. When antimicrobials are used without veterinary or laboratory diagnosis, they may be used for prophylaxis against the risk of a disease without any specific diagnosis, or for growth promotion. Antimicrobials are said to be used for growth promotion when they are used in healthy animals to boost feed efficiency and accelerate weight gain. 

The presence of antimicrobial drug residues, AMR organisms or AMR genes in the food chain poses a threat to food safety and health and welfare of humans and animals alike. By looking at the various steps along the food systems value chain at which these threats emerge, we can identify where innovative interventions may help stem emergent AMR through the food systems. As noted in the figure below, the food value chain extends from the producers, through processors, to consumers. In the subsequent section, we shall outline some innovations and efforts to reduce the need to use antimicrobials in food production

 
 

Explore different targets along the value chain, as well as resources for Innovate4Health teams using the drop-down menus below:

Call to Action for Teams

The teams are invited to envision innovative interventions to disrupt the flow of antimicrobial residues, AMR organisms and AMR genes in food systems and their spillover into the environment or into human healthcare delivery system. Teams should build on existing technological innovations and diagnostic tools, and focus on “inside the box” (Tedx Link) innovations, focusing on what is possible, given the resources and technological tools available.

Student teams will work with the support of expert coaches, speakers, and members of the Coordinating Team to address these issues. Students will learn foundational material related to health equity and systems thinking to better contextualize and address challenging issues in AMR, how to consider the needs and biases of a diverse range of stakeholders and to shift behaviors in a positive direction, and how to advocate for change.