Temperature rise facilitated through anthropogenic climate change is increasingly pressuring global temperate zones (primarily in Asia, Europe, and North America) toward temperature and precipitation profiles more similar to subtropical zones.Reference Rajaud and de Noblet-Ducoudré1 The effect of this pressure is significant with respect to vector-borne diseases.Reference Campbell-Lendrum, Manga, Bagayoko and Sommerfeld2 Rising temperatures lengthen the season and increase the range of disease-carrying insects.3 As temperatures warm, mosquitoes and other warm-weather vectors migrate into higher altitudes and new areas farther from subtropical zones.4 For example, in some regions in the US, warming lengthens the season for disease-carrying mosquitoes.5 Increased precipitation and flooding create more hospitable areas for vector breeding and allows breeding to occur more quickly, as eggs hatch faster in hotter climates.Reference Reinhold, Lazzari and Lahondère6
These challenges will pressure two fissures in the modern system of disease surveillance in the US: between state governments and the federal government and between authorized federal agencies. In this context, those agencies are primarily the Animal and Plant Health Inspection Service (APHIS) of the USDA, and the National Notifiable Disease Surveil-lance System (NNDSS) and the National Center for Emerging and Zoonotic Infectious Diseases (NCEZID) managed by the US Centers for Disease Control and Prevention (CDC). State governments and the Food and Drug Administration (FDA) play important roles as do other federal agencies with some related authority, like Environmental Protection Agency (EPA) and the US Fish and Wildlife Service in the Department of the Interior. The former are generally resource constrained while the latter possess limited authority over specific aspects of vector-borne surveillance activity like anti-microbial resistance (FDA) and water-quality factors affecting animal and human health (EPA).
APHIS, the primary response system for animal health, focuses its surveillance and response efforts on the effect of illness on agricultural production, not on potential human impact.7 This focus affects the broader portfolio of APHIS responsibilities, including evaluations and recommendations as to antimicrobial use in US agriculture. While the US Food and Drug Administration has recommended principles of antimicrobial use shaped by likelihood of emergence of human pathogens, APHIS has deemed that guidance as insufficiently supported by “science-based data on antimicrobial use linked to observed [antimicrobial resistance] in animals.”8 APHIS aims to include other relevant stakeholders, including CDC, in its surveil-lance and response activities, but the actualities of communication and coordination are not codified, predictable, or uniform.
The CDC's NNDSS system, which is aimed at detecting the emergence of pathogens particularly affecting human health, is limited by what state law requires, and then relies entirely on voluntary reporting to CDC for disease cases by state and territorial jurisdictions for nationwide aggregation and monitoring of disease data.9 Its relatively new Center for Emerging and Zoonotic Infectious Diseases covers a wide range of activities, supported by a meager budget that scarcely covers known zoonotic diseases, let alone establish effective surveillance for emerging ones facilitated by climate change.10
This article assesses the adverse effects of this splintered framework for detecting and responding to vector-borne infectious diseases currently, how those adverse effects are likely to be multiplied by climate change, and recommends changes in federal law to address them (specifically law governing relevant agencies). These changes include the use of a dormant coordinating statute, elimination of communication barriers between agencies, and improved relationships with state-level officials.
This article assesses the adverse effects of this splintered framework for detecting and responding to vector-borne infectious diseases currently, how those adverse effects are likely to be multiplied by climate change, and recommends changes in federal law to address them (specifically law governing relevant agencies). These changes include the use of a dormant coordinating statute, elimination of communication barriers between agencies, and improved relationships with state-level officials.
I. Climate Change and Vector-Borne Diseases
Vector-borne diseases result from pathogens transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Worldwide, vector-borne diseases including malaria, dengue, schistosomiasis, Chagas disease, yellow fever, Japanese encephalitis, and onchocerciasis account for more than 17% of all infectious diseases, causing more than 700,000 deaths annually.11 These deaths generally occur in the world's poorest countries, especially those located in tropical and subtropical areas.12
Historically, in the US, malaria and yellow fever imposed significant illness and death, although those numbers declined over the course of the 20th century.Reference Patterson13 The National Malaria Eradication Program, a cooperative undertaking by state and local health agencies of 13 southeastern states and the CDC, commenced on July 1, 1947. In that year, 15,000 malaria cases were reported. By 1950, only 2,000 cases were reported. By 1951, malaria was considered eliminated from the United States.Reference Moreno-Madriñán and Turell14
With respect to tick-borne diseases like Lyme disease and Rocky Mountain Spotted Fever, similar declines registered, especially toward the latter part of the 20th century. Between 1981 and 1992, the Centers for Disease Control collected and summarized 9,223 cases of Rocky Mountain spotted fever (RMSF) reported from 46 states. The annual incidence per million US population decreased from a high in 1981 of 5.2 to a low in 1992 of 2.0.Reference Dalton, Clarke, Holman, Krebs, Fish-bein, Olson and Childs15 Lyme disease was only medically described from the 1970s, and later distinguished in the early 1980s, narrowing the window of available data.16
After decades of declines in the disease burden imposed by vector-borne pathogens in the US, it is now rapidly increasing. A total of 27,388 cases of 16 diseases caused by bacteria, viruses, or parasites transmitted through the bites of mosquitoes, ticks, or fleas were reported to CDC during 2004, and 96,075 cases were reported in 2016.17 Indications are that cases were substantially underreported. Lyme disease accounted for 82% of all tickborne cases, but spotted fever rick-ettsioses, babesiosis, and anaplasmosis/ehrlichiosis cases also increased.18 During 2004–2016, nine vector-borne human diseases were reported for the first time from the United States and US territories. Over that same period, a total of 642,602 cases were reported. The number of annual reports of tickborne bacterial and protozoan diseases more than doubled during this period, from 22,527 in 2004 to 48,610 in 2016.19 The discovery or introduction of novel vector-borne agents will be a continuing threat.20
While there are a number of plausible explanations for these increases — better reporting, the explosion of deer (and therefore tick) populations, increased international travel — climate change is the most significant factor.21 A recent systematic review suggested that nearly two-thirds of European human and domestic animal pathogens were climate sensitive, many to more than one climate driver.Reference McIntyre, Setzkorn and Hepworth22 Because warmer average temperatures can mean longer warm seasons, earlier spring seasons, shorter and milder winters, and hotter summers, conditions are becoming more hospitable for many arthropod carriers of vector-borne diseases.23 The development and survival of ticks, their animal hosts (such as deer), and the bacterium that causes Lyme disease are all strongly influenced by climatic factors, especially temperature, precipitation, and humidity.24 An expansion of the geographic area in which ticks can survive may lead to more people having contact with infected ticks.25 In regions where Lyme disease already exists, milder winters result in fewer disease-carrying ticks dying during winter.26
Mosquito-borne diseases are also likely to increase as temperature conditions warm across the United States. Over the summer of 2017, very moderate autochthonous transmission of Zika took place in southern Florida and Texas.Reference Caminade, McIntyre and Jones27 Dengue is a mosquito-borne viral disease, endemic to tropical regions, but there have been 3 recent US dengue outbreaks in Hawaii, Texas, and Florida.Reference Adalja, Sell and Bouri28 West Nile Virus already is the leading cause of mosquito-borne disease in the US and, as with other vector-borne diseases, is likely to increase with climate change.
Of course, novel pathogens threaten the US population as well. The Bourbon virus was first identified in 2014 in Kansas and is thought (although not proved) to be tick-borne.29 The H1N1 pandemic originated with a novel influenza strain resulting from the mixing of Eurasian and North American swine stocks.30 Although the precise origin remains unknown, the coronavirus disease pandemic (COVID-19) is likely to have emerged from a live animal market.Reference Decaro, Martella, Saif and Buonavoglia31 Because both known and novel pathogens are likely to increase with climate change, state and federal surveillance for vector-borne diseases must be correspondingly shaped and reinforced to prevent, detect, and respond to those threats.
II. Animal Hosts and Vector-Borne Diseases
As a practical matter, animal hosts are not only a crucial source of information about the spread and mutation of vector-borne pathogens, but they are also the reservoir in which mutations are likely to occur. Pathogens transmitted via tick bite, or tick-borne diseases (TBDs), broadly affect domestic animals, livestock, and wildlife worldwide. Ticks feed on a wide range of animal taxa including mammals, reptiles, amphibians, and birds, often using different hosts throughout their life cycle, creating multiple opportunities for disease spread between species.Reference Stuchin, Machalaba and Karesh32 West Nile Virus arrived in the United States only in 1999, but it exploited bird populations to spread across most of the country in just 5 years.33 Rift Valley fever (RVF), a mosquito-borne disease that can kill humans and animals, could cause devastating outbreaks in the United States.34 RVF circulates in livestock — including cattle, sheep, and goats — as well as bats, rodents, and dogs.35
Mutations in animal reservoirs have been responsible for major outbreaks in diseases affecting populations in the US and across the globe. Recent influenza episodes are helpful for understanding the expanding threat. The 2005-06 avian influenza event spread largely through poultry farms in southeast Asia.36 Although the strain has not to date become easily transmissible to humans or between them, when it does infect them, it exacts an approximately 50% fatality rate. The 2009 pandemic H1N1 influenza strain originated with the reassortment of influenza viruses circulating in North American pig herds and among Eurasian pig herds.37 An epidemic of avian influenza in 2014-15 infected or exposed 40 million birds in 20 states.38
In summary, climate change is expanding the range and severity of known vector-borne diseases, those diseases are likely to mutate and spread through animal hosts including and perhaps most importantly livestock and poultry, and public health is best protected by a system that acknowledges and incorporates these principles. Unfortunately, that is not how the US national system operates. Authority over vector-borne disease surveillance is splintered between state and federal governments and, more influentially, between US federal agencies committed to animal and human health. While the mandates of the US Food and Drug Administration and the US Centers for Disease Control and Prevention prioritize tracking and surveillance of vector-borne diseases as they affect human health, the Animal and Plant Health Inspection Service of the US Department of Agriculture, which emphasizes protecting and promoting US agricultural health from foreign pests and diseases, regulating genetically engineered organisms, administering the Animal Welfare Act, and carrying out wildlife damage management activities all of which are broadly guided by industry interests that sometimes, but certainly not always, dovetail with human and public health priorities.
III. The Legal and Regulatory Structure of Vector-Borne Pathogen Surveillance in the US
Federal and state laws delegate to various public health agencies and authorities the responsibility for determining not only when vector-borne pathogens threaten individual and population health but also what measures to take to address those threats. Because states traditionally possessed responsibility for adopting laws to protect the health and safety of their citizens, state governments enjoy significant authority under the US Constitution to determine whether, and under what circumstances, surveillance will be undertaken.39 Federal authority to determine which activities are subject to surveillance reporting is limited to those areas specifically allocated to the US government by the Constitution, for example, when the decision must be made with respect to an animal or person entering the national borders of the United States, when there is a substantial effect on interstate commerce, or where regulation accompanies lawful exercise of the spending power.Reference Fidler, Gostin and Markel40 In the context of COVID-19, Anthony Fauci, Clifford Lane, and Robert Redfield have tied this structure to the ongoing challenge of infectious disease surveillance.Reference Fauci41
The relative distribution of authority is reflected in the number of judicial decisions resolving questions as to the legality and scope of isolation and quarantine.Reference Cole42 While there are few such decisions involving federal law or federal regulations, decisions involving state law are relatively common, especially for contagious diseases like tuberculosis.43 Similarly, state courts to date and the US Supreme Court generally have affirmed the constitutional and lawful basis of stay at home orders, orders limiting the size of public gatherings, and other measures issued during the COVID-19 public health emergency, despite burdens they may impose on speech, assembly, travel, and religious exercise.44 Federal authority over disease surveillance and management largely derives from the Commerce Clause of the US Constitution, which states that Congress shall have the power “to regulate Commerce with foreign Nations, and among the several states.”45 The Public Health Services Act (PHSA) codifies much of this authority, giving the United States Public Health Service responsibility for preventing the introduction, transmission, and spread of communicable diseases from foreign countries to the United States.
The Surgeon General … is [furthermore] authorized to make and enforce such regulations as … are necessary to prevent the … spread of communicable diseases from foreign countries into the States….46 Even under federal authority, Congress has been careful to preserve the applicability of state law, unless it specifically conflicts with an exercise of federal authority.47
During the outbreak of severe acute respiratory syndrome (SARS) in 2002-03 (which had itself jumped from an animal host to humans), some states invoked their own legal authorities to address the outbreak, so it was not necessary for the CDC to invoke federal authority, but it took some measures in parallel with state and local governments as key participants.Reference Misrahi48 The CDC established a series of telephone conferences, whereby federal, state, and local public health lawyers could discuss important legal issues arising under their isolation and quarantine provisions and exchange ideas about specific aspects of those legal issues. The CDC followed a similar pattern during the peak of the monkeypox outbreak in 2003. Additionally, during that outbreak, the CDC developed a web-based clearinghouse where just-issued legal documents such as gubernatorial executive orders and state and local health department rules could be posted. These collaborative measures reduced the time required to identify relevant legal documents and disseminate them to public health lawyers on a “real-time” basis. They are, however, reliant upon good-faith and voluntary participation.Reference Koo and Wetterhall49
A. CDC, the National Notifiable Disease Surveillance System, and the National Center for Emerging and Zoonotic Diseases
This section will first discuss the history of the United States infectious disease surveillance efforts, and then turn to examine the structural defects of the National Notifiable Disease Surveillance System (NNDSS). The weaknesses and funding limitations of that system are contrasted with APHIS, which possesses not only significant resources invested toward surveillance of zoonotic diseases, but has existing infrastructure that may be readily adapted to vector threats accompanying climate change.
With respect to surveillance for vector-borne diseases, the primary preventive infrastructure is based on the CDC's National Notifiable Disease Surveil-lance System (NNDSS) managed by the US Centers for Disease Control and Prevention (CDC). To some extent, surveillance of the type managed by NNDSS has existed for over 100 years in the US In 1874, the Commonwealth of Massachusetts Board of Health asked physicians to notify them weekly in regard to specific infectious diseases.50 Michigan later passed a law requiring immediate notification to the Board of Health of any diseases that could threaten public safety.
At the same time, Congress established the predecessor to the Public Health Service, to collect morbidity reports from overseas.51 With Congress increasingly intervening into infectious disease surveillance, some conflicts arose between state and federal mandates. Eventually states acknowledged that what occurred in neighboring states was relevant to their own surveil-lance efforts, and the federal government could play an important role in “the collection and dissemination of data” in a rapid manner.52
In 1912, state and territorial governments agreed with the US Public Health Service as to the importance of weekly reporting of five (vector-borne) diseases and monthly reporting of ten others.53 After the establishment of CDC in 1946, its chief epidemiologist, Alexander Langmuir, urged state epidemiologists to discuss and determine which diseases should be reported. Today, this “list” or rather, form of documentation, is known as the National Notifiable Disease Surveillance System (NNDSS) and it centers around “reportable” and “notifiable” diseases.54
NNDSS remains dependent upon state authority, which is the only level at which reporting is mandatory. The reporting of a notifiable diseases begins with health care providers, who report to local or county health departments. From there, data is transmitted to the state health department. The state health department may, but not must, then transfer this data to CDC. This can prevent complete and accurate information from reaching the NNDSS since reporting to the federal government is voluntary. At the federal level, a communication system referred to as NETSS (now NEDSS) was created. NEDSS is a standardized form of transmitting and recording data. Even with this system, there remain inconsistencies between data reported and disseminated. The NEDSS is meant to “ensure the public is notified and that prevention efforts are underway.”55 The 2019 list of nationally notifiable diseases includes approximately 120 specific diseases and conditions. Out of 16 reportable vector-borne diseases, only 1 of them — yellow fever — has a vaccine that individuals can use to protect themselves against infection, and the burden of these diseases continues to grow.56 The NNDSS publishes provisional surveillance data weekly for dissemination to the public and provides annual tables of finalized data that are released approximately six months after year end. The data can be viewed in total or by disease, month of occurrence, age group, sex, race or ethnicity.
The voluntariness of the system provides few incentives for accuracy or use of the data collected, which in any case is not oriented toward either surveillance for novel viruses, spillover probabilities, nor even vector-borne diseases. Local and state governments freely concede that they lack the resources necessary to undertake comprehensive surveillance and that they struggle to explain the importance of information requested by CDC.57 A 2013 report by the National Association of County and City Health Officials recommended a stable and standard strategy for reporting notifiable diseases that may cross state and federal borders.58 The report further noted CDC's slow processing of data sent by states, lack of or poor communication by CDC, multiple schedules and standards for sending data to CDC, slow development and challenges of implementing message mapping guides (MMGs), the need for better feedback loops on submitted data to increase data quality, lack of resources, the need for more CDC appreciation of local surveillance workflow processes, and the need for better standardized state-to-state data exchange.59 At least 28 states are not following US Centers for Disease Control and Prevention guidelines on reporting new COVID-19 cases.Reference Holcombe60
CDC oversees the National Center for Emerging and Zoonotic Infectious Diseases, under which sit the Division for Vector-Borne Diseases and a One Health office. The Center dates to 2010, after the global experience with H1N1 but has been criticized as inattentive to the interface between animal and human diseases.Reference Arrizabalaga, Davis and González61 Its 2012-17 strategic plans reveal policy foci on rabies, Lyme disease and dengue virus along with laudable international work. Although NCEZID has developed surveillance assistance for LMICs, it has not adopted similar tools domestically.Reference Salyer, Silver, Simone and Behravesh62 Moreover, it shares the same weaknesses as the NNDSS — inadequate funding and dependence on a fractured system of state and local government cooperation.63
Key state government coordinating bodies have identified weaknesses in the NNDSS and NCEZID systems for a world in which climate change is likely to facilitate the spread of vector-borne diseases in the US and increase the risk for novel pathogens and pathways to emerge.64 Although federal programs like the NNDSS are necessary “for developing emergency surveillance in response to national outbreak,” they lack sufficient funding, coordination, and reach to optimally protect the US population.65
B. USDA and APHIS
While NNDSS and much of NCEZID operates upon voluntary participation of state governments and is oriented toward infectious diseases, the US Department of Agriculture separately runs a disease surveil-lance system, of approximately similar age, oriented toward animals and plants, the Animal and Plant Health Inspection Service, or APHIS. It has helped with the overseeing of disease in the US and the threat of diseases from imported agricultural goods. However, unlike CDC (or even FDA, which along with some other federal agencies has some authority relevant to surveillance of vector-borne diseases), APHIS focuses on human consumption and consumer goods rather than human health. As its mission provides:
APHIS works in a variety of ways to protect and improve the health, quality, and marketability of our nation's animals, animal products and veterinary biologics. This subject area describes many of the diseases facing animals today, as well the steps APHIS is taking to prevent, control, and eliminate those conditions.66
Although APHIS has far more extensive presence and authority over potential sources of vector-borne diseases accompanying climate change, both its mission and its decision-making structures obstruct the use of its infrastructure to prepare for this threat to human health in the US Indeed, in the aforementioned monkeypox outbreak in the US in 2003, APHIS took the position that it could not prohibit foreign animal sources of the disease because it did not affect animal livestock health.67
APHIS took its contemporary form around 1972, although it was preceded by the Veterinary Division of USDA and then the Bureau of Animal Industry, in 1883 and 1884, respectively. The division was established to “promote livestock disease research, enforce animal import regulations, and regulate the interstate movement of animals.”68 In 1912, the Federal Horticultural Board was established to monitor crop diseases and in 1953, the two merged as USDA's Agricultural Research Service. In 1972, meat and poultry inspection divisions were added and APHIS was created.69 In 1977, those two divisions were relocated into the Food Safety and Inspection Service's predecessor agency. In 1985, APHIS gained authority over regulating veterinary biological products. In the late 80s, APHIS was given Foreign Service status allowing the division to have international influence.
Along with CDC and FDA, APHIS has become one of the three leading US governmental entities for monitoring, preventing, and protection from diseases originating in animals and plants. Yet its budget and infrastructure are vaster. APHIS's FY 2021 budget is over $2B compared to NCEZID's budget of $500M. Alone, APHIS accounts for one-third of the FDA's budget of $238M for animal drugs and feeds programs. Indeed, APHIS has a budget roughly half the size of NCEZID for scrutinizing foreign regulatory and disease surveillance practices as trade restrictive. APHIS is oriented toward “the protection and promotion of US agricultural health,” emphasizing that the failure to do so may jeopardize food exports. 70
The U.S. Department of Agriculture's (USDA) Animal and Plant Health Inspection Service (APHIS) — specifically, Veterinary Services (VS) within APHIS — has responsibility for the aspects of livestock health that have a national or international scope or impact. These aspects include preventing the intrusion of foreign livestock pests or diseases through activities at U.S. ports and in foreign countries, detecting and monitoring animal diseases in the United States, carrying out emergency control and eradication operations if foreign pests or diseases enter the United States, and combating certain domestic animal diseases.71
This is true for climate change — facilitated threats as well. While acknowledging that climate change may expand known vector-borne pathogens and introduce new ones, the agency has in fact retreated from previous statements connecting climate change and increased pests, while re-emphasizing the agency's purpose to “safeguard the health, welfare, and value of American agriculture and natural resources.”72 In a 2014 article reviewing APHIS-Wildlife Service's activities with diseases likely to increase as a function of climate change, the APHIS authors conceded that APHIS had the surveillance and technical expertise to manage or support increased surveillance for Chagas disease, plague, leishmaniasis, Lyme disease, and rabies, but, with the limited exception of the plague, had no active programs for doing so.Reference Crom, Burroughs, Knobler and Lederberg73 For example, addressing Lyme disease, the authors noted that “No current [APHIS-Wildlife Service] programs are aimed at ameliorating the impacts from Lyme disease on humans and domestic animals. However, since I. scapularis abundance has been related to white-tailed deer abundance, several options for control of which [APHIS-Wildlife Services] is well-suited do exist.”Reference Algeo74
There is no legal or even practical reason why APHIS cannot share or even integrate its infrastructure and resources with the disease surveillance mandates of CDC, EPA, FDA, or any other federal agency committed to preventing vector-borne pathogens from sickening or killing more people in the US as climate change facilitates their reach. The Commissioner of Food and Drugs, the Director of the CDC, and the Secretary of Agriculture are statutorily charged with coordinating the surveillance of zoonotic diseases as part of the Public Health Security and Bioterrorism Preparedness and Response Act of 2002.75 This act establishes procedures and responsibilities in preparation for a bioterrorist attack or a public health emergency. The 2002 act was aimed at preparedness for public health emergency, although that emergency was contemplated in light of anthrax attacks occurring in the latter part of 2001.76
APHIS, CDC, and FDA maintain multiple MOUs and less formalized cooperative agreements across a range of activities.77 In 2011, APHIS, the CDC, and FDA implemented the Interagency Food Safety Analytics Collaboration (IFSAC), an attempt to consolidate data as well as develop and implement analytical techniques in order to improve detection, prevention, and response to foodborne illness.78 IFSAC was implemented in an attempt to come up with a common strategic plan, improve coordination, and deal with high priority projects. Led by CDC, the program shows the promise of interagency understandings and priorities. Elaborated more fully below, it also illustrates the tendency of USDA generally and APHIS specifically to not share information readily.
As with CDC, APHIS maintains an extensive network of programs, activities, and meetings aimed at coordinating state-level surveillance, although as with CDC, much of that participation is voluntary.79 APHIS employs individuals in more than 28 states and is working on developing new methods of data gathering and analysis in an attempt to further increase disease surveillance. In response to the COVID-19 pandemic, APHIS is playing a primary coordinating role with state governments to address food shortage and safety aspects of response.80
Like CDC and FDA, APHIS works extensively with foreign and international partners, coordinating with over 300 foreign animal disease diagnosticians in teams with other specialists to help identify, track, and analyze foreign animal diseases and plant pathogens.81 Yet this capacity is oriented toward facilitating access to foreign markets for agricultural exports, not for surveillance as it is undertaken more broadly for human diseases and not toward those facilitated by climate change. APHIS plays
a vital role in ensuring the free flow of agricultural trade by keeping U.S. agricultural industries free from pests and diseases and certifying that the millions of U.S. agricultural and food products shipped to markets abroad meet the importing countries' entry requirements.82
C. Weaknesses in the Animal-Human Disease Surveillance Interface
As the foregoing discussion has illustrated, CDC, the agency charged with protecting the US population from health threats, possesses relatively limited authority and resources to address the new and reemerging diseases likely to accompany climate change. APHIS, on the other hand, possesses both authority and resources over some of the most important sources of health threats accompanying climate change, but its mission and infrastructure are not only oriented toward animal and plant health, but are so in ways that emphasize consumption and export, rather than detection, prevention, and response for human pathogenic diseases. While there have been sporadic and uneven partnerships between the agencies as to discrete issues, there is no comprehensive strategy as contemplated by 7 U.S.C. § 8319, the statute that orders the Secretary of Agriculture, the CDC Director, and the Commissioner of Food and Drugs to coordinate the surveillance of zoonotic diseases. The result is both communication and coordination weaknesses that could fail to identify and manage new disease threats.
Some of the communication and coordination barriers are formal, while others are inherent in the respective bureaucracies. Consider avian influenza, which represents a threat to both agricultural poultry as well as humans. APHIS-Veterinary Services runs the National Poultry Improvement Plan, which is how much of the surveillance for avian influenza is conducted for both commercial and backyard poultry operations. While surveillance is approximately divided into “low” pathogenicity and “high” pathogenicity classifications, those do not correspond to the risk of human infection, illness, and death.83 In January 2016, highly pathogenic avian influenza (HPAI) A(H7N8) virus and low pathogenicity avian influenza (LPAI) A(H7N8) virus were detected in commercial turkey flocks in Dubois County, Indiana. Receipt of contact information for responders by the local health department was delayed in the initial stages because of the urgency and complexity of the animal health response. The highly pathogenic virus in that outbreak emerged as a result of spontaneous mutation in a circulating low pathogenic virus. A study conducted after the outbreak found that the highly pathogenic virus exhibited enhanced virulence in mouse and ferret models, but that only the low pathogenic strain was transmissible; however, transmissibility in mammals and capacity to rapidly acquire increased virulence is a concerning combination of characteristics. Although APHIS has unpublished coordination guidance with CDC, the animal response prevailed over the human response as a function of routine surveillance.Reference Kile, Ren and Liu84 The NPIP is the only federal program responsible for H5/H7 low pathogenicity surveillance, response, and containment activities.Reference Brown85
However, APHIS does not generally coordinate well with other federal programs and has been known to be poor at inter-agency communication. In 2010, the Government Accountability Office (GAO) conducted a study to identify gaps in the regulatory systems overseeing animal importation and disease prevention. One area that they found particularly troubling was the importation of live animals. While relevant agencies had “collaborated to meet their responsibilities by taking actions in five areas — strategic planning, joint strategies, written procedures, levering resources, and sharing data,” Reference Thompson86 APHIS's inability and/or unwillingness to share information under its control was identified as a primary obstacle to the prevention of disease importation.Reference Smith, Ganesh, Burger and Gundlach87 GAO recommended specific data sharing platforms and database interfaces as an important solution.88
The tendency of APHIS to withhold information is also demonstrated by the Swine Futures Project, an APHIS-industry effort to improve overall swine health in the US The National Center for Import and Export (NCIE) and CDC, among other federal organizations have stated APHIS's preference to withhold information.89 “The culture of APHIS is not to communicate and … no staff gives up information voluntarily.”90
D. Solution: Coordinated Framework for the Detection of Vector-Borne Pathogens
Because 7 U.S.C. § 8319, the aforementioned public health emergency statute, requires APHIS, CDC, and FDA to coordinate with respect to infectious diseases, there is already an existing legal mechanism through which to establish a more effective and rational framework to better detect, prevent, and respond to vector-borne diseases accompanying climate change. Although that statute's rule of construction somewhat unhelpfully provides that it is “not to be construed to alter the jurisdiction between the Secretary of Agriculture and the Secretary of Health and Human Services,” it remains possible to duplicate a framework adopted for regulated biotechnologies, the Coordinated Framework for the Regulation of Biotechnology (“Coordinated Framework”).
Genetically modified products, like vector-borne pathogens, implicate the jurisdiction of several federal agencies. In 1986,
In response to the rise in new genetic engineering processes, such as the use of recombinant DNA … the Coordinated Framework [was formed] in 1986 to ensure the safety of biotechnology products. This framework was subsequently updated in 1992, and recently by the Obama administration in 2017 … The Coordinated Framework mainly brought together three agencies deemed to have regulatory oversight for relevant existing statutes — the EPA, FDA, and USDA — and ensured coordination between the agencies …92
The Coordinated Framework clarifies the roles and responsibilities of each agency, develops a long-term strategy to ensure that future risks are assessed efficiently, and requires a combined report that assesses the future landscape of biotechnology. This regulatory process continues to evolve and has proven to be effective in assessing the safety of many GMO crop products.93 As biotechnology impacts the areas of agriculture, environmental protection, and food and drugs, the rules set for GMOs span across all three agencies, and the three must collaborate to set regulations and enforce them. The USDA is responsible for monitoring modified organisms for pest risk, the EPA ensures safe pesticides are used, and the FDA ensures proper labeling of modified organisms.Reference Lafrance94
A similar “Coordinated Framework” could operate with respect to surveillance and management of vector-borne diseases, especially as they proliferate with climate change. For example, an April 2020 study showed that domesticated species harbored an average of 19.3 zoonotic viruses; with pigs, cattle, and horses sharing 31 viruses with humans.Reference Johnson95 The study also found that domesticated species commonly shared viruses with each other, and also commonly shared viruses with wild animal species within their respective orders. A Coordinated Framework could develop criteria for lead agencies for specific pathogens, most efficient means of containment, and sharing of information, thus better managing outbreaks like that of low-pathogenicity avian influenza in Dubois County, Indiana and other outbreaks elsewhere. APHIS has already identified pathogen areas where its infrastructure could work in support of CDC objectives if only called to do so.
A Coordinated Framework for vector-borne pathogens could materialize through a standing committee comprised of representatives of APHIS, CDC, and FDA. That committee would identify areas of agency lead and expertise, and better identify human liaisons who could circumvent digital interoperability barriers.Reference Dooley96 The Coordinated Framework Committee could allow for animal and human health perspectives to operate in parallel, and, when necessary, together. The recent update to the Coordinated Framework laid out coordination mechanisms that the EPA, FDA, and USDA already utilize. These mechanisms include Formal and Ad Hoc Interagency Working Groups and Memoranda of Understanding. Interagency working groups and interagency communication also helps to bring in expertise from other relevant agencies. Indeed, the Coordinated Framework has been able to incorporate climate change-related innovations like genetic modifications of male Aedes aegypti mosquito and could be adapted to cover not only biotechnological products, but vector surveillance as well.Reference Dobert97
A Coordinated Framework would also address many of the obstacles posed by coordination with state level officials. Reports made by state officials relevant to livestock, for example, could be channeled through decision-making criteria that lead to CDC-led investigations and response. State-level reporters would therefore have a greater likelihood of engaging the most competent agency. The Coordinated Framework, as it exists for biotechnology, requires consultation with state, tribal, and local governments.
IV. Conclusion
The benefits of a modern, more streamlined, and more sensible regulatory scheme can ease the CDC and APHIS's goal of early detection of spillover pathogens and mutations in known pathogens. A different regulatory scheme, that places detection, prevention, and response, into the hands of the most qualified to deal with it, would better prepare the US for the threat that vector-borne diseases pose, especially as their reach and severity spread with climate change. The current, fractured, regulatory system that currently manages vector-borne threats is archaic and inadequate. Zoo-noses cause approximately 2.7 million deaths and 2.5 billion cases of sickness each year worldwide, and the US will increasingly be affected as it warms.98 The proposal set forth in this article is based upon an existing, workable framework, and better leverages the resources and infrastructure of the federal agencies tasked with keeping the US safe from vector-borne diseases.
