According to USDA, SECD are characterized by an acute, rapidly spreading viral diarrhea of pigs. No other species, including humans, are known to be affected, and these diseases are not a direct public health threat. Pigs develop varying degrees of diarrhea and loss of appetite depending upon the age of the pig infected. Piglets are the most severely affected and have the highest mortality rates (50 to 80 percent), while growing and adult pigs have the lowest rates (approximately 1 to 3 percent). PED was first recognized in England in 1971 and has been known to exist in China since 1973. According to USDA’s SECD case definition document, China has seen a large increase in outbreaks since 2010, and the emergence of new strains of PED have been attributed to this increase. USDA’s case definition document also provides information about the presence or suspected presence of PED and PDCoV in the United States and other countries. For example, the first outbreak of PED in the United States was reported in May 2013. PED has also been reported in Mexico and Canada, as of August 2013 and January 2014, respectively. Further, as of June 2014, PED is thought to be widespread throughout most regions of Western and Central Europe and Southeast Asian countries. In addition, PED is suspected in parts of South America. PDCoV is more recent and less widespread; it was first reported in China in 2012, in the United States in January 2014, and later in Canada according to the document. USDA’s mission includes protecting and improving the health, quality, and marketability of our nation’s animals and animal products by working to prevent, control, or eliminate animal diseases, and by monitoring and promoting animal health and productivity. USDA’s overall budget request was $23 billion in fiscal year 2015, of which $287 million was budgeted for the agency’s animal health efforts, including disease response. USDA comprises multiple organizations that support its animal health mission; see table 1 on the next page for selected organizations and their specific missions and roles. In carrying out its animal health mission, USDA participates in surveillance and preparedness, as well as response efforts for animal diseases. Surveillance activities can be conducted to monitor animal health, or in response to a specific disease. Animal disease surveillance consists of collecting, analyzing, and interpreting animal health data to detect diseases early, enable rapid reporting and response during disease outbreaks, and control the spread of disease. According to USDA guidance, the agency also can use such data for accurate risk analysis, which includes assessing present, future, and emerging threats to animal health, and estimating the likelihood of a damaging event and the resulting consequences. As part of the agency’s preparedness and response efforts, USDA has identified certain animal diseases that pose a risk and must be reported if they occur in the United States. Data collected on these diseases are used to estimate their geographic distribution and severity, which inform officials’ response efforts. For example, USDA established program diseases to control or eradicate specific diseases that must be reported to federal and state animal health officials. The agency works with federal- state-industry stakeholders to control or eradicate these diseases. USDA describes program diseases as serious zoonotic diseases, diseases that are economically important, or diseases of concern to the livestock, poultry, or aquaculture industries. Among these program diseases, some are designated as foreign animal diseases, which, in addition to being reported to USDA must be reported to the international community. USDA defines a foreign animal disease as a terrestrial animal disease or pest, or an aquatic animal disease or pest, not known to exist in the United States or its territories. A foreign animal disease may involve livestock, poultry, wildlife, or other animals. The World Organisation for Animal Health (formerly known as the Office of International Epizooties or, more commonly by its previous acronym, OIE) develops the list of internationally reportable animal diseases. This list is used by OIE’s 180 member countries when determining trade restrictions on animals or animal products that pose a risk to their agricultural industries. According to USDA’s guidance about animal diseases, one of the most immediate and severe consequences of an incident of an OIE-Listed animal disease in the United States is the loss of export markets. For example, according to the USDA’s Economic Research Service website, as a result of the current outbreak of highly pathogenic avian influenza—an OIE-Listed disease—as of June 2015, 15 countries, including China, Russia, and South Korea, have banned poultry imports from the United States with many other countries placing bans on U.S. states or regions. Rapid response to diseases can prevent or limit sudden, negative consequences for animal health, economic security, and food security. Additionally, a rapid response can help normal production to resume as quickly as possible. When deciding on and implementing actions to respond to outbreaks of animal disease, USDA collaborates with other federal agencies, state officials, and with industry. For example, USDA works with FDA, which, among other things, is responsible for ensuring the safety of feed, to investigate potential feed contamination; state animal health officials and state departments of agriculture to assist in disease control efforts such as data collection; and industry to implement biosecurity practices that are critical to limiting disease entry and spread. For example, diseases can be introduced or spread to healthy animals via footwear and outerwear, but biosecurity practices such as changing or covering these items before entering premises can help prevent the introduction of disease. Similarly, changing or covering these items after working with infected animals can prevent the spread of disease. According to USDA’s Animal and Plant Health Inspection Service’s strategic plan, collaborative efforts are thought to produce more public value than any single agency could produce. Components of these efforts include the identification of roles and responsibilities and mutually agreed upon common outcomes, such as the control or eradication of a disease, as well as joint strategies for achieving the agreed-upon outcome. USDA did not take regulatory action during the initial response to the SECD outbreak, beginning in May 2013 when the PED virus was first detected, because it did not believe then that such action was necessary to manage the outbreak. By not taking regulatory action, USDA had limited information about the initial geographic distribution of the diseases; their modes of spread; and the locations of the first infected herds, which could have helped identify the source of entry of the diseases in the United States. USDA did not take regulatory action during the initial response when SECD were identified in May 2013. According to USDA officials, the agency was reluctant—and did not believe it was necessary—to take regulatory action, such as requiring reporting of infected herds or restricting the movement of pigs. Such action could have had negative financial impacts on the swine industry, according to USDA documents. Instead, the agency initially supported swine industry-led efforts to address SECD. Moving Pigs Pigs are often moved among multiple premises at different stages of their life spans to accommodate their growth in size. Typically, pigs are moved by truck and trailer as shown in the picture below. Additionally, the U.S. Department of Agriculture (USDA) estimates that more than 600,000 pigs are transported to slaughter on any given day in the United States. According to industry representatives and USDA, movement restrictions such as a quarantine lasting more than a week could potentially result in euthanasia of hundreds of thousands or millions of animals, depending on how long the quarantine was in place, since premises may not be able to humanely house pigs larger than they customarily handle. The agency’s decision not to take regulatory action took into account several factors, including that these diseases were not listed as internationally reportable animal diseases, do not pose a threat to people, and were not lethal to all pigs. If USDA had designated these as foreign animal diseases within the United States, the agency might have been expected to impose quarantines, and other countries might have restricted the importation of pigs or pig products. According to USDA guidance for reportable and foreign animal diseases, import restrictions could potentially have severe consequences because U.S. animal agricultural industries are becoming more dependent on exports, and the long-term strategic plans of these industries call for increasing the amount of goods sold abroad. Porcine Epidemic Diarrhea Virus (PED) Strains The U.S. Department of Agriculture and other researchers have reported on more than one strain of PED presently in the United States. According to recent research, two strains identified in the United States closely resemble the strains of PED virus circulating in China; however, genetic resemblance does not indicate how the virus arrived in the United States. USDA officials told us that, at that time of their decision, varying strains of PED were known and active around the world, and the agency and the swine industry were aware of how PED spread (via fecal contamination). At that time, USDA believed the best course of action was for industry to manage SECD according to an agency announcement about the diseases. USDA officials explained that industry was already leading the response to other swine diseases, such as transmissible gastroenteritis. The initial response by industry and USDA to the SECD outbreak included efforts to learn more about these diseases. Within 3 months of the first PED diagnosis, one of the main swine industry associations— the National Pork Board—made $800,000 available for research to learn about PED and potential ways to control the disease, such as through promoting maternal (sow) immunity. USDA provided support and collaborated with industry associations in the response.