(AP) — The federal government is starting a new program to help monitor and possibly control the spread of a virus that has killed millions of pigs since showing up in the U.S. last year.

The porcine epidemic diarrhea virus, believed to be from China, causes severe diarrhea in newborn piglets, who die from dehydration.

The U.S. Department of Agriculture announced Friday it is stepping up efforts by requiring farmers to report infections and labs where farmers send tissue and fecal samples to report positive tests.

Farms that suffer an outbreak also will have to participate in a program to help control the spread of the disease

Previously, the USDA and the nation’s pork industry tracked the disease with voluntary reports from the labs.