A recent report by the International Livestock Research Institute (ILRI), Nairobi/Kenya, identifies key evidence gaps in our knowledge of livestock- and fisheries-linked antimicrobial resistance in the developing world and documents on-going and planned research on this topic by key stakeholders.
The Review of evidence on antimicrobial resistance and animal agriculture in developing countries was written by veterinary epidemiologist and food safety expert Delia Grace of the International Livestock Research Institute (ILRI).
Antimicrobial resistance (AMR) occurs when microorganisms (bacteria, viruses, fungi and parasites) develop the ability to continue growing in the presence of an antibacterial, antiviral, antifungal or antiparasitic substance to which they were previously sensitive. The use of antibiotic drugs to prevent and treat livestock diseases is a key driver for the development of agriculture-related AMR, which now represents a global public health problem, as antibiotics in food animals can enter the food chain and affect the health of consumers and communities, Grace writes.
The ILRI scientist further notes that in developing countries, antimicrobial resistant pathogens are commonly found in animals, animal food products and agro-food environments. However, the lack of national surveillance systems means that we do not have reliable estimates of the true burden of antimicrobial resistant infections in developing countries.
In addition to a lack of accurate information on antibiotic use in developing countries, there is limited understanding of the sources of AMR in animal agriculture and the relative importance of different sources, Grace warns.
The report reviews the knowns and unknowns of:-
According to the report, the underlying driver for antimicrobial use and development of AMR is the livestock and aquaculture revolutions enabling rapid growth in intensive production systems in response to an increased demand for livestock and fish products. In turn, this demand is driven by population increases, urbanisation, improving economic conditions and globalisation in developing countries and is predicted to continue to increase. Based on livestock intensification patterns, China, Brazil and India are current hotspots, and Myanmar, Indonesia, Nigeria, Peru and Vietnam are future ones. Based on aquaculture trends, China is a hotspot, while Indonesia, Thailand, Vietnam, Bangladesh, India and Chile are other countries where antimicrobial use in fish production may be problematic.
Many interventions using educational, managerial, regulatory and economic approaches to improve drug use have been studied, Grace states, adding that training by itself is relatively ineffective, but when combined with strategies to change market conditions (by changing incentives and accountability environment), better success has been achieved. There are many animal husbandry options that can allow production without non-therapeutic antimicrobials, but these options have not been widely used in, or adapted to, developing countries.
The report concludes with a call to address the global problem of AMR through an evidence-based approach which includes filling knowledge gaps, careful piloting of interventions and rigorous evaluation of success and failure.
Citation:Grace, D. Review of evidence on antimicrobial resistance and animal agriculture in developing countries. Evidence on Demand, UK (2015) iii + 39 pp.