Ohio State researchers are looking for a unique way to test and trace the spread of Porcine Epidemic Diarrhea Virus, a deadly swine disease that causes high mortality rates among piglets.
Funded by the National Pork Board, virologists Linda Saif and Qiuhong Wang are working on a six-month project that involves growing the virus in the lab and using this material to develop a serological test, which will allow scientists to determine how widespread PEDV is in the U.S. swine population.
"Serology allows you to trace the history of the outbreak through antibodies," said Saif, an expert on viral diseases of swine and cattle. "This is very important in this case because we don't know how and where PEDV got into the U.S., and how it is spreading across state lines."
PEDV has been identified in 15 states. Its May discovery in the U.S. marked the first time the disease had been identified within the states. Currently, there is no vaccine or treatment for the disease. Biosecurity measures are the only way to protect herds.
That's why growing the virus in cell culture and developing a serological test are important steps for the future development of a vaccine against PEDV, Saif said.
PEDV belongs to the coronavirus family, which is known to cause respiratory and intestinal diseases in mammals and birds. It has been present in Europe since the 1970s and in Asia since the 1980s. PEDV causes intestinal disease in swine, especially young pigs. It is transmitted via feces or insects contaminated with feces.
PEDV does not sicken humans and does not impact the safety of pork products.
"The entire U.S. swine population is at risk of this disease because it doesn't have any immunity to the virus," Saif said. "We have seen 50-100% mortality in baby pigs. Adult pigs only show mild illness, but the problem is that the pigs can become carriers of the virus and spread it to other pigs."
PEDV is difficult to identify because its symptoms, which include vomiting, diarrhea, poor appetite, dehydration and depression, are almost identical to those of transmissible gastroenteritis virus, another coronavirus.
Because testing can only be done in the lab, it's important to be vigilant about swine handling and take precautions to disinfect hog areas frequently.
"With fair season upon us, fair boards and 4-H clubs need to take precautions and monitor for the disease," Saif said. "You will have a conglomeration of animals from many different farms coming together at one place, and people going back and forth. This could help spread the disease among pigs."