PORCINE EPIDEMIC DIARRHEA VIRUS IS A DEADLY CORONAVIRUS DISEASE AFFECTING PIGS. IT FIRST ENTERED THE US PIG POPULATION IN 2013 AND IS ESTIMATED TO CAUSE MORE THAN $600 MILLION PER YEAR IN ECONOMIC LOSSES FOR THE PIG INDUSTRY. THE MORTALITY RATE FOR NEWBORN PIGLETS IS CLOSE TO 100%. VACCINES FOR PORCINE EPIDEMIC DIARRHEA VIRUS EXIST, BUT THEY ARE NOT VERY GOOD. KILLED VIRUS VACCINES PROVIDE ONLY PARTIAL PROTECTION. MODIFIED LIVE VIRUS VACCINES CAN REGAIN THE ABILITY TO CAUSE DISEASE. NONE OF THE AVAILABLE VACCINES CAN PROTECT NEWBORN PIGLETS WHEN GIVEN TO PREGNANT SOWS. WE AIM TO DEVELOP BETTER VACCINES FOR PORCINE EPIDEMIC DIARRHEA VIRUS, USING A NEW, RAPID, EXTREMELY INEXPENSIVE VACCINE TECHNOLOGY THAT WE HAVE DEVELOPED. THE VACCINES WILL PROVIDE IMPROVED PROTECTION FOR THE PIGS, HELP DECREASE COSTS TO PIG FARMERS BECAUSE THEY WILL NO LONGER LOSE PIGS TO THE DISEASE, AND HELP AMERICAN CONSUMERS BY DECREASING THE COST OF PORK. WE HYPOTHESIZE THAT THESE NEW VACCINES WILL PROVIDE MUCH BETTER PROTECTION AGAINST PORCINE EPIDEMIC DIARRHEA VIRUS THAN CURRENTLY AVAILABLE VACCINES. THE SPECIFIC OBJECTIVES OF OUR WORK ARE TO: 1) MAKE VACCINES THAT YIELD BETTER PROTECTION FOR THE PIGS, 2) TEST THE ABILITY OF THE VACCINES TO PROTECT YOUNG PIGLETS AGAINST PORCINE EPIDEMIC DIARRHEA VIRUS, AND 3) TEST THE ABILITY OF THE VACCINES, WHEN GIVEN TO PREGNANT SOWS, TO PROTECT HER NEWBORN PIGLETS AGAINST PORCINE EPIDEMIC DIARRHEA VIRUS. WE EXPECT THAT OUR NEW VACCINES WILL PROVIDE PROTECTION AGAINST PORCINE EPIDEMIC DIARRHEA VIRUS TO YOUNG PIGLETS AND TO NEWBORN PIGLETS WHEN THE PREGNANT SOW IS VACCINATED. WE ANTICIPATE THAT OUR NEW VACCINES WILL PROVIDE SAVE THE US PIG INDUSTRY HUNDREDS OF MILLIONS OF DOLLARS PER YEAR. WE ALSO ANTICIPATE THAT IN THE COURSE OF DEVELOPING THE NEW VACCINES, WE WILL LEARN MORE ABOUT HOW TO MAKE IMPROVED VACCINES USING OUR NEW METHODS THAT WILL HELP US DEVELOP OTHER VACCINES THAT TARGET OTHER DISEASES PLAGUING AMERICAN AGRICULTURE.