Veterinary-related Factors Influencing the Global Spread of AMR
Veterinary-related factors that influence the global spread of AMR include the following:
1. Increase in population, demand for food animal protein and global changes in animal production systems.
The Center for Strategic and International Studies estimates that the world population increases by about 8,700 people every hour, 146 people every minute or 2.5 people every second. From 1950 to the year 2000, the population roughly doubled from 3 billion to 6.3 billion (Figure 2) and is projected to continue to increase in the years to come45.
Understandably, food production must also increase to meet these increased nutritional demands. However, because of urbanization and industrialization, available agricultural lands continue to shrink and livestock production has become compromised in many regions45.
In reaction to the increasing demand for food and the decreasing available agricultural land, most livestock and poultry are now raised in smaller spaces at the least possible cost and pushed to the fastest possible rate of gain. This often requires reliance on antibiotics for treatment, metaphylaxis or growth promotion; thereby creating concomitant increased rates of AMR.
2. Changing trends in animal trading and increased movement of animals and animal byproducts.
The international trade in livestock and livestock products is a growing business, accounting for about one sixth, by value, of all agricultural trade46. To liberalize international trade, the General Agreement for Tariffs and Trade (GATT) was established in 1947. Recognizing that animal health and food safety standards could be nontariff barriers to international free trade, the World Trade Organization (WTO) also incepted Sanitary and Phytosanitary (SPS) measures. The Office International des Epizooties (OIE) was tasked to set appropriate global standards for animal health, while the Codex Alimentarius Commission sets standards for food safety47. These standards facilitated safer international movement of animals and animal by-products around the world. However, these generally do not prevent the spread of AMR across the globe due to resistant bacterial organisms that may be hitchhiking in animal products and healthy animals.
Increased movement of animals and animal by-products has also been facilitated by technological improvements in travel and transport systems. It used to be that food products with short shelf lives could not be moved to distant markets, but what used to take weeks and months to transport can now be moved within a day or even less. This rapid movement increases the likelihood that bacteria will remain viable while in transit, further increasing the risk that AMR genes can quickly spread around the world.
3. Lack of Global Initiative Regarding AMR
In many countries there is little surveillance information or control efforts regarding rates of antimicrobial usage or AMR in food or food animals. Such programs are expensive, and may also require a strong political will to counter the influence of some who may not want information revealed that might scare consumers, jeopardize pharmaceutical sales or negatively affect exports or imports. Also, many countries have much more pressing issues such as feeding their people, fighting wars and developing their economies.