[This article originally appeared in the May/June issue of JSHAP. I was encouraged to reprint it in e-Letter as well. Your comments are welcome.]
Even as bad as it is, porcine epidemic diarrhea (PED) could have been so much worse. If this had been a foreign animal disease, the economic and production impacts would have been devastating. The PED virus (PEDV) gives us an opportunity to evaluate our surveillance, mitigations, vulnerabilities, and response structure. This outbreak has clearly shown our weaknesses in all those areas. The safeguards designed to prevent introduction of foreign pathogens into the United States failed. Biosecurity interventions at the farm failed. Ability to rapidly diagnose emerging pathogens failed. Capability to transfer information efficiently and seamlessly between diagnostic laboratories and within the laboratory network failed. Producers and veterinarians failed to contain the disease. The US Department of Agriculture (USDA) and the industry failed to prepare for this scenario. Obviously, there is enough blame to go around and we all have some soul-searching to do. So let’s get started.
We need a better strategy to address disease threats globally. We knew PEDV was a significant disease of swine in Asia. People working and consulting in China experienced the disease and heard about its significance. Dr Robert Desrosiers even included it in his report to the 2012 AASV Swine Health Committee. We chose to ignore the warnings. More than 30 viruses affect swine worldwide today. Let’s make sure we’re monitoring these diseases, identifying and addressing knowledge gaps, and promoting research to ensure we can detect these pathogens.
We need the resources to pursue emerging disease diagnosis in the United States. Today, once it has been determined that an emerging disease is not a foreign animal disease, it’s up to the producer and the practitioner to pursue a definitive diagnosis. The earliest known PED case was not diagnosed for at least a month. Rapidly identifying the index case greatly increases our options for minimizing a disease’s potential impact on animal health.
Once PEDV was identified, the veterinary diagnostic laboratories developed, validated, and implemented diagnostic and differential tests and ramped up capacity to handle more samples. However, collation and communication of epidemiological information, even within the National Animal Health Laboratory Network (NAHLN), was less than seamless and efficient. This communication failure is widely recognized: 12 years after NAHLN’s inception, its laboratories still cannot electronically share data in an efficient, seamless manner. The NAHLN recently received authorization for $15 million in the 2014 Farm Bill. Most agriculture and veterinary groups, including AASV, strongly supported this request because we see the value of a unified, integrated network of laboratories that can support animal agriculture and respond to disease outbreaks. We’ve got to begin functioning as a true national network for the betterment of animal agriculture. If this outbreak had been foot-and-mouth disease, with dozens of laboratories involved, information transfer would have been unmanageable using current practices.
The government agencies responsible for preventing incursion of pathogens into the United States need to conduct a thorough analysis of the potential routes of pathogen transmission and implement effective surveillance and mitigation protocols to prevent and detect introduction of foreign pathogens. That’s their job. No one else can do that. The USDA needs the resources to monitor disease activities internationally and to work with other countries to better understand the threat foreign animal diseases pose to US agriculture. The USDA also needs to be able to monitor internal disease movements. Emerging diseases should be reportable at the state and federal level. The USDA should be able to help producers and veterinarians monitor disease transmission and disease status at the herd, state, and national levels.
Producers and veterinarians are the first line of defense. Early in the PEDV outbreak, practitioners stepped up to the plate and reported something was wrong. They worked with the laboratories to obtain an accurate diagnosis and reported results to their clients, neighbors, and animal-health officials. I commend these veterinarians and their clients for their actions. We need to ensure that we provide complete and thorough information when submitting samples to the diagnostic laboratories, including Premises Identification Numbers (PINs) and proper designations of animal age or stage of production. The accuracy of this information is critical to conduct meaningful epidemiological and disease monitoring. PINs are included on < 20% of diagnostic submission forms. Most swine farms have a PIN: use it on all official forms and diagnostic submissions. Go to pork.org to print barcodes for swine premises, and affix the barcode to the submission form.
On a positive note, many things worked well. The laboratories quickly developed diagnostic tests, pork producers appropriated funds for research, researchers responded quickly, and USDA’s Center for Epidemiology and Animal Health collaborated on epidemiological efforts. Veterinarians are discussing their observations and participating in efforts to better understand the movement of this disease. State animal-health officials have been engaged and cooperative, and AASV has worked collaboratively to conduct epidemiological surveys, produce educational materials, and provide expertise. The real failure would be not learning from this experience and failing to work together to identify and correct our shortcomings.