The source of Swine Enteric Coronavirus Diseases in the United States will likely never be known because USDA officials didn’t do epidemiological outbreak investigations at the site where it was first diagnosed.
A Government Accountability Report released in December reviewed federal actions related to the outbreak, which began in May 2013. The GAO recommends that USDA make changes in its process to “clarify and document how it will respond to emerging diseases, including defining roles and responsibilities.”
Porcine Epidemic Diarrhea (PED) virus and Porcine Deltacoronavirus (PDCoV) are known as Swine Enteric Coronarvirus Diseases. PED emerged in the United States in 2013 and PDCoV emerged in 2014. These diseases do not affect public health, but have 50% to 80% mortality rates among piglets. The mortality rate drops to 1% to 3% for grown hogs.
The study found:
1. USDA did not take regulatory action during the initial response to the outbreak, which limited its understanding of the geographic distribution, spread and source of the diseases.
2. USDA did not take regulatory action during the initial response because the agency didn’t believe it was necessary and feared action would have had negative financial impacts on the swine industry. If USDA had designated the SECD as foreign animal diseases within the United States, the agency may have been expected to impose quarantines and other countries might have restricted the import of U.S. pigs or products.
3. “USDA had limited information on SECD geographic distribution and mode of spread and can’t definitively identify how the diseases entered the United States.” USDA didn’t initially require reporting of infected herds and producers were reluctant to voluntarily share the information with USDA. The limited information USDA received suggested the diseases were spreading quickly across state lines.
4. USDA collaborated with universities and industry associations to understand how SECD may have spread.
5. Beginning in June 2014, USDA issued an order imposing reporting requirements and provided financial assistance to states and producers. USDA has provided about $26 million to help manage SECD.
6. According to several stakeholders, the most important USDA actions for helping to manage the diseases were providing financial assistance for diagnostic testing and requiring reporting.
7. In September 2015, USDA released a retrospective root cause study that says transport carrier totes are the most likely source of entry for the diseases.
8. USDA has proposed a list of reportable diseases and drafted guidance for responding to emerging animal diseases. It has also proposed a list of animal diseases that must be reported. However, it has not detailed who has what responsibilities in putting its response in place.
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