Abstract
Demand for animal protein for human consumption is rising globally at an unprecedented rate. Modern animal production practices are associated with regular use of antimicrobials, potentially increasing selection pressure on bacteria to become resistant. Despite the significant potential consequences for antimicrobial resistance, there has been no quantitative measurement of global antimicrobial consumption by livestock. We address this gap by using Bayesian statistical models combining maps of livestock densities, economic projections of demand for meat products, and current estimates of antimicrobial consumption in high-income countries to map antimicrobial use in food animals for 2010 and 2030. We estimate that the global average annual consumption of antimicrobials per kilogram of animal produced was 45 mg·kg⁻¹, 148 mg·kg⁻¹, and 172 mg·kg⁻¹ for cattle, chicken, and pigs, respectively. Starting from this baseline, we estimate that between 2010 and 2030, the global consumption of antimicrobials will increase by 67%, from 63,151 ± 1,560 tons to 105,596 ± 3,605 tons. Up to a third of the increase in consumption in livestock between 2010 and 2030 is imputable to shifting production practices in middle-income countries where extensive farming systems will be replaced by large-scale intensive farming operations that routinely use antimicrobials in subtherapeutic doses. For Brazil, Russia, India, China, and South Africa, the increase in antimicrobial consumption will be 99%, up to seven times the projected population growth in this group of countries. Better understanding of the consequences of the uninhibited growth in veterinary antimicrobial consumption is needed to assess its potential effects on animal and human health.
Generated Summary
This research employs statistical models, integrating livestock density maps, economic forecasts of meat demand, and current antimicrobial consumption data from high-income countries, to map and project global antimicrobial use in food animals. The study aims to address the absence of quantitative measurements of global antimicrobial consumption by livestock and to understand the potential consequences of antimicrobial resistance. The methodology involves Bayesian statistical models, spatial mapping, and projections based on livestock production and economic growth. The study’s scope includes 228 countries, with a focus on estimating and mapping antimicrobial consumption in food animals for 2010 and projecting trends for 2030. It examines the correlation between antimicrobial use and the rise of antimicrobial-resistant bacteria (ARBs), considering different livestock species and production systems. The research also explores the geographic distribution of antimicrobial consumption and its implications for public health, especially in the context of increasing demand for animal protein in low- and middle-income countries.
Key Findings & Statistics
- The global average annual consumption of antimicrobials per kilogram of animal produced was estimated at 45 mg·kg⁻¹ for cattle, 148 mg·kg⁻¹ for chickens, and 172 mg·kg⁻¹ for pigs.
- Between 2010 and 2030, the global consumption of antimicrobials is projected to increase by 67%, from 63,151 ± 1,560 tons to 105,596 ± 3,605 tons.
- Up to one-third of this increase is attributed to shifting production practices in middle-income countries.
- The increase in antimicrobial consumption in livestock between 2010 and 2030 is projected to be 99% in Brazil, Russia, India, China, and South Africa (BRICS) countries.
- In 2010, the five countries with the largest shares of global antimicrobial consumption were China (23%), the United States (13%), Brazil (9%), India (3%), and Germany (3%).
- By 2030, the ranking is projected to be China (30%), the United States (10%), Brazil (8%), India (4%), and Mexico (2%).
- Among the 50 countries with the largest amounts of antimicrobials used in livestock in 2010, Myanmar (205%), Indonesia (202%), Nigeria (163%), Peru (160%), and Vietnam (157%) are likely to have the greatest projected percentage increases in antimicrobial consumption by 2030.
- Antimicrobial consumption in Asia is projected to be 51,851 tons by 2030, representing 82% of the current global antimicrobial consumption in food animals in 2010.
- In Asia, as much as 46% of the increase in antimicrobial consumption by 2030 is likely due to shifts in production systems.
- In Asia, the antimicrobial consumption in chicken and pigs is expected to grow by 129% and 124% respectively, by 2030.
- The total acreage of areas where antimicrobial consumption is currently greater than 30 kg·km⁻² will grow by 4% for pork and 143% for chicken.
- The global estimate of antimicrobial consumption in food animal production in 2010 was 63,151 (±1,560) tons.
- The projected increase in antimicrobial consumption by 2030 is 67%, reaching 105,596 (±3,605) tons.
Other Important Findings
- The study highlights the association between antimicrobial use in livestock and the emergence of antimicrobial-resistant bacteria (ARBs), which poses significant public health implications.
- It points out that the use of antimicrobials in intensive livestock production is a major driver of antimicrobial resistance, with potential consequences for both animal and human health.
- The research indicates a significant geographic heterogeneity in antimicrobial consumption, with hotspots in South and Southeast Asia, the Americas, and specific areas in Africa.
- The study emphasizes the role of shifting production practices in middle-income countries, particularly in Asia, where intensive farming systems are replacing extensive ones, leading to increased antimicrobial use.
- It underscores the need for initiatives to preserve antibiotic effectiveness while ensuring food security, particularly in low- and lower-middle-income countries.
- The research suggests that the absence of clear legislative frameworks on antimicrobial use in many middle- and low-income countries could lead to increased irrational consumption.
- The study points out that the total volume figures do not account for choices of drugs, potential differences in drug potencies, resistance selection pressures, or use for treatment in human medicine.
Limitations Noted in the Document
- The study relies on assumptions and limitations due to the scarcity of data on antimicrobial use in livestock, especially in middle- and low-income countries.
- Estimates for antimicrobial consumption were obtained for only 32 countries (all high-income) and extrapolated to others, which may introduce uncertainties.
- The modeling strategy assumes that intensive farming operations use similar quantities of antimicrobials across different income levels, which might not be entirely accurate.
- The study’s estimates of antimicrobial consumption in 2010 may represent an overestimation of current consumption levels.
- The study does not evaluate antimicrobial consumption on a compound-specific basis, which is a limitation in assessing the impact of specific drugs.
- The exclusion of ionophores (used only in animals) from the analysis could affect the accuracy of the results.
- Simplifications in production processes, like treating semi-intensive pig farming as an individual category, could affect the overall estimates.
- The study acknowledges that the absence of clear legislative frameworks on the use of antimicrobials in livestock production in most middle- and low-income countries may result in increased irrational consumption.
- The data used to train the statistical models were from countries with bans or partial bans on antimicrobial use for growth promotion, which might lead to an underestimation of antimicrobial consumption in other regions.
Conclusion
The study’s findings emphasize the need for urgent and coordinated action to limit the overuse and misuse of antimicrobials in food animal production. The projections indicate a substantial increase in global antimicrobial consumption by 2030, driven significantly by the rising demand for meat in middle- and low-income countries. The study underscores the potential implications of uncontrolled antimicrobial use, which includes increased antimicrobial resistance, and also has wide-ranging effects, including the emergence of ARBs through trade and transport networks. It also highlights that the current trends in intensive livestock farming, particularly in rapidly growing economies, are contributing to a global increase in the prevalence of ARBs. In essence, if regulatory action is not implemented, the global antimicrobial consumption in food animals will grow substantially by 2030, leading to a compound annual growth rate similar to the human consumption. These findings call for a multi-faceted approach involving surveillance, international collaboration, and the eventual phasing out of antimicrobials for growth promotion. The challenge lies in balancing the need for food security with the imperative to preserve the effectiveness of antimicrobials, necessitating concerted efforts from governments, industry stakeholders, and international organizations. As the authors conclude, this situation underscores the urgency of tackling the misuse of antimicrobials in food animal production, particularly in regions where the livestock sector is rapidly intensifying, to safeguard both animal and human health.