KANSAS CITY, Mo. – Japan has issued new rules aimed at stopping the spread of porcine epidemic diarrhea virus (PEDv).

Live pigs exported from the United States and Canada must certify their animals come from facilities free from PEDv for at least 12 months. Additionally, the pigs must also test negative for the virus during the pre-export isolation period. Officials from Japan explained the new regulations to a World Trade Organization committee.

Reported PEDv cases totaled 7,893 in 30 states as of July 26, according to data from the National Animal Health Laboratory Network. NAHLN reported that 29.3 percent of the 26,954 pig farm samples tested since November 2013 have returned positive for PEDv.

A US Department of Agriculture report on the US hog herd showed the domestic hog herd as of June 1, 2014, at 95 percent of the year-ago level, or 62.128 million head. The total fell below analysts’ expectations of 63.2 million head, 97.1 percent of the 2013 herd. USDA attributed the decline in swine numbers to rapid spread of PEDv.