ENID, Okla. —
In the past year, United States swine producers have been battling a new biological enemy.
First discovered in May 2013, porcine epidemic diarrhea virus (PEDV) has caused significant challenges to the swine industry. As of April 9, the American Association of Swine Veterinarians reported 28 states, including Oklahoma, have confirmed cases of PEDV. Specific to the swine species, PEDV will not affect other livestock and poses no risk to human health. Due to the short incubation period of the disease (12-24 hours from exposure to advent of clinical signs) and its ability to thrive in a variety of environments, PEDV has caused significant damage to the swine industry since its introduction into the United States less than one year ago.
Clinical signs of PEDV include diarrhea and vomiting in pigs of all ages. Once exposed, suckling pigs will not survive the disease; however, weaned pigs (older than two weeks of age) will have symptoms ranging from mild to severe. There is currently no vaccine for PEDV, and for this reason, current treatment procedures are basic: Hydration, electrolyte supplementation and a dry, draft-free living environment. Demonstrated throughout the industry, PEDV will lead to a high mortality rate, regardless of treatment method. Pigs that do recover will shed the virus for three to four weeks.
Organisms like PEDV that cause disease in pigs can be present on many different surfaces. Organic matter, such as dirt, mud, feces, snow and water, are perfect environments for diseases to thrive. These materials can be easily transferred on via clothing, boots, panels, shovels and trucks, potentially spreading a disease. The swine industry is well known for its biosecurity measures; however, the effect of PEDV shows what once were considered effective control measures now must be evaluated to prevent additional spread of PEDV and other potential diseases.
Many swine producers affected by PEDV fully understand the negative biological effects of this disease on their herd. However, until recent nationwide reports were published, little was known about the full extent of the damage to the nation’s swine herd. According to the USDA Hog and Pig Report released on March 28, United States hog inventory was down 3 percent from 2013, the lowest inventory since 2007. In Oklahoma, overall hog inventory was 13 percent lower than March 2013. The virus also has traveled across the border into Mexico, where reports show 30 percent of the country’s herd has been exposed. Additionally, three provinces in Canada have reported PEDV; however, the virus is in early stages and the full effect is not yet known.
A recent forecast by Rabobank reported that 12.5 million fewer hogs will be slaughtered in 2014, resulting in a 6-7 percent decline in overall U.S. pork production. Due to this significant decline in supply, consumers are feeling the pinch at the meat counter as the price of pork has increased 45-50 percent over 2013 levels (Chicago Board of Trade).
As mentioned before, there is no vaccine for PEDV, but research is in full swing at a number of research institutions to better understand the virus. The similarity of PEDV to another swine virus called transmissible gastroenteritis virus (TGE) has given scientists some insight into how the virus can be controlled.
The clock is ticking for swine producers in North America. Increased biosecurity measures have helped to a certain degree; however, the only way to eliminate this virus completely is through the consistent use of a proven vaccine. Some research findings from the University of Minnesota have shown that viability of PEDV diminishes with increasing temperatures. This has given producers hope that PEDV cases will recede in the coming summer months giving researchers time to discover effective methods of treatment and control.
For additional questions or information regarding PEDV, contact your local county extension educator.
Zook is Oklahoma Cooperative Extension Service area livestock specialist.