Naomi Jennings is a law student in the HLS Food Law & Policy Clinic and a guest contributor to this blog.
According to USDA’s Animal and Plant Health Inspection Service (APHIS), “[u]p to 75 percent of emerging infectious diseases in humans are zoonotic, impacting the health of both humans and animals.” Meanwhile, the World Health Organization (WHO) placed antimicrobial resistance on their list, “Ten threats to global health in 2019.” The risks posed by sustained animal-human contact and antibiotic and antiviral drugs make animal agriculture a biosecurity risk. The 2023 Farm Bill should consider both viral and microbial security risks and mitigation strategies.
Emerging Pandemic Risks
The current SARS-CoV-2 pandemic well illustrates that pandemic-causing viruses are frequently not confined to one species. SARS-CoV-2 variants have been detected in 19 other species: cat, dog, tiger, lion, gorilla, snow leopard, otter, spotted hyena, mink, mule deer, white-tailed deer, binturong, coati, cougar, ferret, fishing cat, lynx, mandrill, and squirrel monkey. Though domestic livestock are unlikely to have contributed or to contribute in the future to the SARS-CoV-2 pandemic (experimentally, domestic livestock showed low susceptibility to infection and did not shed detectable infectious virus), livestock have contributed to past pandemics and endemics. These past diseases include H5N1 bird flu (chickens), H1N1 swine flu (pigs), and MERS (camels). Livestock can also contribute to bacterial-caused pandemics, as was the case for bovine tuberculosis.
The Farm Bill could attempt to address these issues. APHIS is currently working with participating zoos and aquariums on the Zoo and Aquarium Serology Study, a study designed to gather information on SARS-CoV-2 through a serology study on zoo animals, a biosecurity assessment of participating institutions, and testing peridomestic animals such as mice, rats, and raccoons for SARS-CoV-2. This study was funded through the American Rescue Plan Act, but the Farm Bill could also address biosecurity risks by directing APHIS to more consistently and more proactively test farms for emerging pandemics.
Antimicrobial Resistance
Another biosecurity threat is the development of antimicrobial resistance, or in other words, the decline in efficacy of antimicrobial drugs. This threat contemplates microbes such as bacteria, viruses, protists, or fungi becoming resistant to most or all antibiotic, antiviral, or antifungal drugs, resulting in increased human mortality. Many organizations, including the IDSA Emerging Infections Network, the CDC, and the WHO, have identified bacterial antibiotic resistance particularly as a rising threat. This post will focus on antibiotic resistance, though more research on antiviral and antifungal drugs is also desirable. One of the largest antibiotic risks comes from antibiotic overuse in animal agriculture, meaning that there is room for USDA to act on this issue.
USDA is already involved in efforts to mitigate antibiotic resistance, including as part of the National Action Plan for Combating Antibiotic-Resistant Bacteria, in concert with the FDA, and through the Agricultural Research Service. Though the level of domestic sales and distribution of medically important antimicrobial drugs used for livestock has significantly decreased from a high in 2015, there has also been a slight increase since 2016, and there is no clear downwards trend between 2017 and 2020. The Farm Bill could incentivize the USDA to adopt new approaches to combat antibiotic resistance. USDA could fund high-throughput sequencing (HTS) (also known as next-generation sequencing), a term that describes novel technological approaches to genetic sequencing that are much cheaper than traditional (Sanger) sequencing. HTS could be used in two distinct ways. Firstly, HTS could be used to characterize bacteria by identifying novel strains of antibiotic resistant bacteria, identifying what antibiotic resistant traits the bacteria may have, and tracking the relation between different strains (like ancestry.com for bacteria). In addition to HTS’s bacteria-related use, HTS could be used to better understand host responses to viral infections, improving understanding of the physiological conditions caused by the pathogen. USDA could also fund systematic attempts to identify the source of antibiotic resistant bacterial infections in hospitalized patients. Molecular typing technology, which includes sequencing, can be used to identify similarity between strains (creating a bacteria family tree), which can then be used to identify likely sources of infection. For example, methicillin resistant Staphylococcus aureus (MRSA) strains can be classified into various buckets, and community-associated MRSA. Identifying the closest bacteria “relatives” to bacteria found in hospitalized patients could provide insight into the largest biosecurity risks. Systematically typing bacteria in hospitalized patients could reveal patterns in infections that could be used to identify emerging strains in a community, and potentially link those strains to a source such as a hospital or a confined animal feeding operation by also typing bacteria in samples taken from hospitals or confined animal feeding operations. A collaboration along these lines between USDA and the Centers for Disease Control and Prevention (CDC) could allow patients to understand where they acquired their bacterial infection.
USDA could also develop a large, standardized system for detecting antibiotic resistance. This could potentially be modelled after WHO’s Global Antimicrobial Resistance and Use Surveillance System (GLASS), which standardizes collecting, analyzing, and sharing data while providing routine surveillance and focused surveillance. CDC already supports an Antimicrobial Resistance (AR) Solutions Initiative that aims to detect and respond to antimicrobial resistant infections, but USDA can and should use its unique jurisdiction over the agriculture sector to provide a more thorough analysis of risks within agriculture. USDA could systematically collect samples from all major animal agriculture operations that are using antibiotics and identify the strains of bacteria found in each sample. This could be especially useful in detecting where emerging strains of antibiotic resistant bacteria are appearing and better understanding the link between antibiotic use in animals and antibiotic resistance.
Finally, USDA could support research on developing novel antibiotics and developing novel antimicrobial products that can be used in place of antibiotics in livestock. Pharmaceutical companies have largely moved away from developing novel antibiotics because antibiotics are not profitable, especially in comparison with other classes of drugs (such as cancer drugs, for example). USDA could support funding for developing novel drugs with agricultural applications. Responsible use and management of any novel antibiotics will be necessary to avoid pathogens quickly developing resistance to new drugs. Therefore, funding research into identifying drugs that can be used as replacements for antibiotics in agriculture is also an important research area for USDA to support in order to lower antibiotic use in the agriculture industry.
The views and opinions expressed on the FBLE Blog are those of the authors and do not necessarily reflect the official policy or position of FBLE. While we review posts for accuracy, we cannot guarantee the reliability and completeness of any legal analysis presented; posts on this Blog do not constitute legal advice. If you discover an error, please reach out to contact@farmbilllaw.org.
